Journal of Pediatric Psychology Advance Access published March 30, 2015
Journal of Pediatric Psychology, 2015, 1–10 doi: 10.1093/jpepsy/jsv012 Systematic Review
Systematic Review and Meta-Analysis of Anxious and Depressive Symptoms in Caregivers of Children With Asthma
School of Psychology, The University of Sydney All correspondence concerning this article should be addressed to Caroline Hunt, PHD, School of Psychology, Brennan MacCallum Building A18, The University of Sydney, NSW 2006, Australia. E-mail: [email protected] Received June 11, 2014; revisions received January 27, 2015; accepted February 2, 2015
Abstract Objective To provide a review of the literature comparing anxious and depressive symptoms in caregivers of children with asthma with caregivers of healthy children. Method A systematic search identified 25 studies from 17 articles, reporting outcomes on 4,300 caregivers of children with asthma and 25,064 caregivers of healthy children. Results Overall, anxious (d ¼ 0.50) and depressive symptoms (d ¼ 0.44) were higher in caregivers of children with asthma compared with caregivers of healthy children. Age, site of recruitment, and whether the asthma diagnosis was medically confirmed were included as potential moderators. The relationship between parental psychopathology and asthma was stronger in those with medically confirmed asthma and participants recruited from clinical settings. Other moderators were not significant. Conclusions Caregivers of children with asthma appear to have greater anxious and depressive symptoms than caregivers of healthy children, but the reasons are unclear. More research that investigates modifiable factors that may moderate this association is urgently needed. Key words: anxiety; asthma; children; depression; meta-analysis; motherhood.
Asthma is the most common chronic illness of childhood, with an estimated prevalence rate of 7–10% worldwide (Lazarus, 2010). Similar to other childhood chronic illnesses, the impact of asthma is not limited to the child experiencing asthma, but affects all family members. The primary caregiver, most commonly the mother, is usually responsible for managing their child’s asthma in the home (McQuaid, Kopel, Klein, & Fritz, 2003). Particularly early on in a child’s life, it is the caregivers who have the responsibility of monitoring their children’s breathing and making medical decisions such as when to administer rescue medications (McQuaid et al., 2003). Caring for a child with asthma, therefore, may place a significant burden on the caregiver, which may adversely affect their mental health (Frankel & Wamboldt, 1998; Kaugars, Klinnert, & Bender, 2004). Conversely, the caregiver’s mental health may affect the development or outcome of the child’s asthma. A number of studies have found a positive association between maternal distress and asthma outcomes (Bartlett et al., 2004; Kaugars et al., 2004; Tibosch, Verhaak, & Merkus, 2011). The reason for this association is not
well understood, but it has been suggested that caregiver mental health may affect treatment adherence in children (Anderson, Bailey, Cooper, Palmer, & West, 1983). It has even been found that maternal distress predicts the development of asthma or wheezing in their offspring (Cookson, Granell, Joinson, Ben-Shlomo, & Henderson, 2009; Kozyrskyj et al., 2008; Lefevre et al., 2011; Wright, Cohen, Carey, Weiss, & Gold, 2002). Identification of mental health disorders among caregivers of children with asthma, therefore, is of clinical importance, both in terms of caregiver well-being and child asthma outcomes.
Caregiver Mental Health in Other Chronic Illnesses A number of studies have found that caregivers of chronically ill or disabled children generally experience a higher rate of depression and anxiety compared with caregivers of healthy children. In a meta-analysis investigating the prevalence of depression among mothers of children with developmental disabilities, results showed
C The Author 2015. Published by Oxford University Press on behalf of the Society of Pediatric Psychology. V
All rights reserved. For permissions, please e-mail: [email protected]
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Gemma Easter, PHD Candidate, Louise Sharpe, PHD, and Caroline J. Hunt, PHD
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Comparisons With Normative Samples and Other Chronic Illnesses Studies investigating differences in anxious and depressive symptoms in caregivers of children with asthma versus the general population have shown mixed results. One study found that depressive symptoms among caregivers of children with asthma were higher than in the general population, with 33% of caregivers experiencing at least mild depressive symptoms (Szabo, Mezei, Kovari, & Cserhati, 2010). Another study reported prevalence rates of depressive symptoms among caregivers of asthma at 26.7% (Brown et al., 2006). This compares with reported 12-month prevalence rates of 9.5% in normative samples (Kessler, Chiu, Demler, Merikangas, & Walters, 2005). Another study found no differences in anxious symptoms between caregivers of children with asthma and the general population (Gupta, Mitchell, Giuffre, & Crawford, 2001). Similarly, studies investigating differences in anxious and depressive symptoms between caregivers of children with asthma and caregivers of children with other psychiatric or medical illnesses have, in general, found no differences (e.g., vs. chronic renal disease; Szabo et al., 2010; vs. congenital heart disease; Gupta et al., 2001; vs. cystic fibrosis; Yilmaz et al., 2008). While the above information is useful, these studies lack a nonclinical or healthy comparison group, which makes it difficult to estimate the degree to which anxious or depressive symptoms may differ between caregivers of children with and without asthma. For this reason, the current review will only include studies comparing anxious and depressive symptoms in caregivers of children with asthma and caregivers of healthy children, and exclude studies comparing symptoms with normative samples or caregivers of children with other medical or psychiatric diagnoses.
Moderating Influences on Caregiver Anxiety and Depression It is not only of interest to know whether caregivers have higher levels of anxiety and depressive symptoms than caregivers of healthy
children, but it is also important to know what factors might contribute to these higher symptom levels. Reviews of the literature have indicated a number of potential family influences on childhood asthma, although this research is still in its infancy. It has been suggested that family emotional characteristics, such as parental mental health and stress, are associated with more severe asthma (Lange et al., 2011). Similarly, asthma management, including adherence, and smoking status are thought to be important in the management and development of pediatric asthma (Cabana et al., 2004). Socioeconomic factors, ethnicity, and physiological factors, such as genetic influences, may all affect the onset of childhood asthma and its outcomes (see Kaugars et al., 2004). It is possible that these factors may be associated with both poor maternal mental health and more severe childhood asthma (see Celano, 2006). However, while a number of these potentially important factors have been systematically investigated in the literature on childhood asthma in general, they are not routinely reported in the literature investigating caregiver mental health and childhood asthma. As a result, in this review we have focused on potential methodological factors and child’s age as potential moderators of the relationship between childhood asthma and caregiver anxious and depressive symptoms. It might be expected that caregivers of younger children with asthma are more at risk of developing anxiety and depression compared with caregivers of older children. There are two main reasons for this. First, younger children typically have more severe symptoms, which tend to become better controlled as they age. Second, parents tend to bear more of the responsibility and burden of looking after younger children (McQuaid et al., 2003). For example, Streisand et al. (2005) found a negative association between parental stress and children’s age in a study on childhood diabetes. Similarly, the informant used to report asthma symptoms may affect the strength of the relationship between caregiver mental health and child asthma; however, the direction of this relationship is not clear. Wamboldt et al. (1998) found that parents with significant stressors tend to overreport their child’s internalizing symptoms. Therefore, it is possible that parents who are anxious may also interpret wheezing as asthma, and hence overreport a history of childhood asthma. On the other hand, a medically confirmed diagnosis of asthma may reflect greater severity of illness, and therefore, the relationship between caregiver mental health and child asthma may be stronger for studies relying on diagnostic measures than those that rely on parent-report measures, as the burden of care may be greater. For the same reason that children with severe symptoms are more likely to be seen in tertiary referral centers rather than the community, the site of recruitment, may also influence the degree to which anxious and depressive symptoms differ between groups of caregivers. It may be that anxious and depressive symptoms are greater in caregivers recruited from clinical samples versus community samples, as studies undertaken at a tertiary care center or specialized clinic may involve children who are likely to be most seriously affected by asthma, and therefore, their caregivers may be at greater risk for anxiety or depression.
Study Aims The aim of the current meta-analysis was twofold. The first aim was to assess whether anxious and depressive symptoms were greater among caregivers of children with asthma compared with caregivers of healthy children. The second aim was to investigate the following moderators: age of the child, informant of asthma diagnosis, and site of recruitment. We predicted that differences in symptoms
Downloaded from http://jpepsy.oxfordjournals.org/ at University of Nebraska-Lincoln Libraries on September 27, 2015
that mothers of children with developmental disabilities are at elevated risk of depression compared with mothers of healthy children (Singer, 2006). Similarly, a systematic review found that depressive symptoms among mothers of children with epilepsy was higher compared with mothers of children without epilepsy, with 50% of mothers of children with epilepsy estimated to be at risk of depression (Ferro & Speechley, 2009). Other studies have found that both anxious and depressive symptoms are higher in caregivers of children with cystic fibrosis (Yilmaz et al., 2008), psychotic disorders (RydeBrandt, 1990), and speech impairments (Rudolph, Rosanowski, Eysholdt, & Kummer, 2003) compared with caregivers of healthy children. A recent review found that stress was higher in parents of children with a range of chronic illnesses, including asthma, compared with parents of healthy children (Cousino & Hazen, 2013). Given the similarities in caring for children with asthma and other childhood chronic illnesses (Barlow & Ellard, 2006; Nuutila & Salantera, 2006), it would not be surprising if caregivers of children with asthma were particularly at risk for developing mental health problems compared with caregivers of healthy children. However, to date, we know of no review that has been conducted comparing anxious and depressive symptoms in caregivers of children with asthma and caregivers of healthy children. Despite this, there have been a number of individual studies that have compared caregivers of children with asthma with normative samples and caregivers of children with other chronic illnesses.
Easter, Sharpe, and Hunt
Anxiety and Depression in Caregivers of Children With Asthma
3
between the caregivers of children with asthma and caregivers of healthy children would be significantly greater when children were younger, when asthma had been medically diagnosed, and when children were recruited from a clinical setting.
2 because it included data for family members rather than mothers or primary caregivers, and 1 because the article was not written in English. Following this search process, 17 articles, reporting on 25 between-group comparisons, were retained for inclusion in the meta-analysis. These studies reported on the outcomes of 4,300 caregivers of children with asthma and 25,064 caregivers of healthy children. The process of study selection is shown in Figure 1.
Method Search Strategy
Inclusion and Exclusion Criteria To meet the inclusion criteria, a study needed to (a) involve caregivers of children or adolescents (18 years old) with an asthma diagnosis based on either a medically confirmed diagnosis or self-/parent-report measures, (b) use a measure of anxiety or depression (rather than a measure of “general distress” or “stress”) in terms of either a diagnosis or symptoms, for which information about the psychometric properties was available, (c) have a comparison group of caregivers of healthy children (i.e., children without asthma or any other medical or psychiatric diagnosis), (d) report statistical information that would allow for the calculation of an effect size, and (e) be written in English. Studies were also excluded if caregivers of children with asthma were compared with population norms on standardized measures.
Study Selection Seven hundred and thirty-eight unique articles were identified through the search strategy. The titles and abstracts of the articles were reviewed by one reviewer (G.E.), and a sample of 362 was reviewed by a second reviewer (C.H.), with good interrater reliability (j ¼ .83). Disagreements were resolved through consensus. Six hundred and ninety-two articles were excluded on the basis of the title and abstract search, as they did not measure anxious or depressive symptoms in primary caregivers of children with asthma compared with caregivers of healthy controls. Eight of these excluded articles reported results for caregivers of children with asthma versus caregivers of other chronic illnesses (e.g., epilepsy, diabetes) but not versus healthy controls The remaining 46 articles were full-text reviewed by two reviewers (G.E. and C.H.) for their relevance to the research question. The interrater reliability was good (j ¼ .81), and disagreements were resolved by consensus. Twenty-nine articles were excluded, as they did not meet full inclusion criteria. Articles were excluded for the following reasons: 14 articles were excluded because they did not use a measure of anxiety or depression, 7 for not providing enough information to calculate an effect size, 5 for not including a healthy control group,
Quality Ratings Articles were reviewed for quality using a modified version of the Quality Index Scale (QIS; Downs & Black, 1998; see Table I for outcomes of quality ratings). The Quality Index was initially developed to systematically rate the research quality of randomized and nonrandomized studies of health-care interventions. The Quality Index was modified to exclude assessment of items relating to intervention studies, including randomization, blinding, and withdrawals and dropouts, which reduced the original 27-item index to 15 items. This modified version was used in a systematic review of depressive symptoms among mothers of children with epilepsy (Ferro & Speechley, 2009). The QIS has good reliability and validity for measuring the methodological quality of health research (Downs & Black, 1998; Olivo et al., 2008; Sanderson, Tatt, & Higgins, 2007; Wang, Collet, Shapiro, & Ware, 2008). Items were scored either 0 (no/unable to determine) or 1 (yes), with a maximum score of 15. The items covered standard of reporting (0–7), external validity (0–3), internal validity (0–4), and study power (0–1), with higher scores indicating articles with higher methodological quality. The first author conducted the quality review on all of the articles. A selection of five articles was reviewed by the third author, with good interrater reliability (j ¼ .87). Any discrepancies were resolved by consensus. The overall mean QIS was 10.7 (SD ¼ 1.7) with scores ranging between 8 and 13 (out of a total score of 15). The mean subscale scores were 5.9 (SD ¼ 0.9) for reporting, 1.4 (SD ¼ 0.8) for external validity, and 3.4 (SD ¼ 0.7) for internal validity. Only one study (Leao et al., 2009) reported a formal sample size or power calculation.
Statistical Approach To determine whether anxiety and depressive symptoms differed among caregivers of children with asthma versus caregivers of healthy children, meta-analytic procedures were used. The following data were extracted by the first reviewer to answer the research questions: sample size and mean age of children in both the asthma and healthy control groups, informant type for asthma diagnosis, site of recruitment, study design, and data needed to compute effect sizes (e.g., mean and standard deviations of anxiety or depressive symptom measures or proportion of caregivers meeting a clinical cutoff score or diagnosis). Attempts were made to contact study authors for additional data as needed. Effect sizes were converted to Cohen’s d (Hedges & Olkin, 1985). For studies reporting means and standard deviations of anxiety and depressive symptom scores, Cohen’s d (the difference between the means of two groups, divided by the pooled standard deviation) was calculated. For studies reporting frequencies or proportions, data were converted into Cohen’s d. In studies where more than one assessment point was included (e.g., prospective studies), we included only the baseline scores. If both mother and father reports were provided, only mother-reported measures were used for comparison purposes because only two studies included separate data from fathers. We considered conducting analyses for those
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A literature search was conducted using the following databases: MEDLINE, PsycINFO, Cumulative Index to Nursing and Allied Health Literature, and Embase. The search was limited to articles published in a peer-reviewed journal and unpublished dissertations between January 1975 and February 2014. The following search terms were used to identify articles meeting the inclusion criteria. The first stem group search terms included “depression” or “depressive symptoms” or “anxiety” or “anxiety symptoms” or “psychological distress.” The second stem group included “mother$” or “maternal” or “caregiver” or “parent$.” The final stem group included “asthma.” Medical Subject Heading (MeSH) terms were exploded to broaden the search for relevant studies. The ancestry method, which involves reviewing the references of those articles included in the meta-analysis and any relevant reviews for other relevant articles not identified in the original search, was used to identify further studies.
4
Easter, Sharpe, and Hunt
Articles identiied with search strategy (n=738)
Articles excluded on the basis of their titles and abstracts (n=692) •
Articles reviewed in depth for relevance (n=46) Articles excluded due to methodological requirements (n=29) • • • • •
No validated measure of anxiety or depression (n=14) Not enough information to calculate effect size (n=7) No healthy control group (n=5) Information not available for primary caregiver (n=2) Articles not written in English (n=1)
Total articles included in the analysis (n=17)
Figure 1. Search and study selection process.
studies that included father data; however, they were insufficient to allow quantitative analyses. All analyses conducted were between groups, meaning a positive sign of d indicates that anxiety or depressive symptoms were greater for caregivers of children with asthma than caregivers of healthy children. Within each symptom variable (anxiety or depression) the mean weighted effect sizes (with withinsubjects effect sizes combined before averaging) were first calculated by a random-effects model because the studies’ effect sizes were not assumed to be drawn from a sample with a single true population effect size. Cohen’s d was interpreted based on the following recommended rules of thumb: 0.2 ¼ small, 0.5 ¼ medium, 0.8 ¼ large (Cohen, 1988). Together with the overall mean, we report the 95% confidence interval (CI), T (or tau, the estimated standard deviation of the true effect sizes), Q (a test for homogeneity of effect sizes across studies), and I2 (a measure of the magnitude of heterogeneity, or the percentage of the observed variance that is real rather than spurious). Subgroup analyses were conducted to examine whether potential moderator variables (informant type for asthma diagnosis and site of recruitment could account for the variability among effect sizes. These analyses used mixed-effect models, consisting of a randomeffects model within subgroups and a fixed effect model across subgroups, consistent with previously published studies (Koenig, Eagly, Mitchell, & Ristikari, 2011). Both models were calculated using the method of moments (Borenstein, 2009). A simple meta-regression
was used to assess the one continuous moderator, child’s age, to determine whether the mean age of participants in each study can account for variance in the effect size of that study. A fail safe N analysis was conducted to address and potential “file drawer” problem (Rosenthal, 1979), such that only positive results are published. Fail-safe N analyses estimate the number of studies that would need to have been conducted and not published before the reported positive results would become null. All analyses were conducted using Comprehensive Meta-Analysis (Version 2.0).
Results Study Characteristics There were 17 articles that were included in the meta-analysis, which reported the results of 25 between-group comparisons (herein referred to as studies). The additional comparisons were because eight of the articles included a measure of both depression and anxiety (see Table I for more details and References for citations of the included articles). The 17 articles reviewed were published over a 37-year period between 1977 and 2014. The articles reported on results for 4,300 caregivers of children with asthma and 25,064 caregivers of healthy children. Of the 17 unique articles reporting the results of 25 comparisons, 10 reported on depressive symptoms and 15 reported on
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• • • •
Anxiety or depression not measured in primary caregiver (n=248) Not asthma focused (n=211) No data available (n=152) No healthy control group (n=77) Not human research (n=4)
Longitudinal
Longitudinal
Cross-sectional
Cross-sectional
Cross-sectional
Cross-sectional
Cross-sectional
Davis (1977) (United Kingdom)
Feldman et al. (2011)
Guxens et al., (2014)
(The Netherlands) Kean et al. (2006) (United States)
Krommydas et al. (2002) (Greece)
Leao et al. (2009) (Brazil)
Ortega, Goodwin, McQuaid, &
Canino (2004) (United States) Ozkaya, Cetin, Ugurad, &
Longitudinal
Tu, Perreault, Seguin, &
g
Cross-sectional
Cross-sectional
Yilmaz et al. (2008) (Turkey)
Yuksel et al. (2007) (Turkey)
Clinical
Clinical
Community
Population-based cohort
Population-based cohort
75
62
50
115
1,109
8.4 (2.9) 7–16
8.1 (2.9)
13.3 (2.7) 8–18
1.4 (0)
7.6 (2.2) 4–11
5–12
Diagnosis
Diagnosis
Diagnosis
Parent report
Parent report
Parent report
Diagnosis
Parent report
Diagnosis
g
46
21
33
1,581
10,090
738e
32
662
90
1,466
160
70
50
4,557
288
101
5,079
N
9.1 (3.6) 7–15
8.8 (3.4)
13.5 (2.0) 9–17
1.4 (0)
7.5 (2.3) 4–11
5–12
7.8 6–9
5–12
4–15
8.2 (3.9)
4–17
2–11
4–8 4.9
6.0 (1.2)
12–18
14.8
6.5
10–25
17.7 (0.3)
Journal of Pediatric Psychology, 2015, 1–10 doi: 10.1093/jpepsy/jsv012 Systematic Review
Systematic Review and Meta-Analysis of Anxious and Depressive Symptoms in Caregivers of Children With Asthma
School of Psychology, The University of Sydney All correspondence concerning this article should be addressed to Caroline Hunt, PHD, School of Psychology, Brennan MacCallum Building A18, The University of Sydney, NSW 2006, Australia. E-mail: [email protected] Received June 11, 2014; revisions received January 27, 2015; accepted February 2, 2015
Abstract Objective To provide a review of the literature comparing anxious and depressive symptoms in caregivers of children with asthma with caregivers of healthy children. Method A systematic search identified 25 studies from 17 articles, reporting outcomes on 4,300 caregivers of children with asthma and 25,064 caregivers of healthy children. Results Overall, anxious (d ¼ 0.50) and depressive symptoms (d ¼ 0.44) were higher in caregivers of children with asthma compared with caregivers of healthy children. Age, site of recruitment, and whether the asthma diagnosis was medically confirmed were included as potential moderators. The relationship between parental psychopathology and asthma was stronger in those with medically confirmed asthma and participants recruited from clinical settings. Other moderators were not significant. Conclusions Caregivers of children with asthma appear to have greater anxious and depressive symptoms than caregivers of healthy children, but the reasons are unclear. More research that investigates modifiable factors that may moderate this association is urgently needed. Key words: anxiety; asthma; children; depression; meta-analysis; motherhood.
Asthma is the most common chronic illness of childhood, with an estimated prevalence rate of 7–10% worldwide (Lazarus, 2010). Similar to other childhood chronic illnesses, the impact of asthma is not limited to the child experiencing asthma, but affects all family members. The primary caregiver, most commonly the mother, is usually responsible for managing their child’s asthma in the home (McQuaid, Kopel, Klein, & Fritz, 2003). Particularly early on in a child’s life, it is the caregivers who have the responsibility of monitoring their children’s breathing and making medical decisions such as when to administer rescue medications (McQuaid et al., 2003). Caring for a child with asthma, therefore, may place a significant burden on the caregiver, which may adversely affect their mental health (Frankel & Wamboldt, 1998; Kaugars, Klinnert, & Bender, 2004). Conversely, the caregiver’s mental health may affect the development or outcome of the child’s asthma. A number of studies have found a positive association between maternal distress and asthma outcomes (Bartlett et al., 2004; Kaugars et al., 2004; Tibosch, Verhaak, & Merkus, 2011). The reason for this association is not
well understood, but it has been suggested that caregiver mental health may affect treatment adherence in children (Anderson, Bailey, Cooper, Palmer, & West, 1983). It has even been found that maternal distress predicts the development of asthma or wheezing in their offspring (Cookson, Granell, Joinson, Ben-Shlomo, & Henderson, 2009; Kozyrskyj et al., 2008; Lefevre et al., 2011; Wright, Cohen, Carey, Weiss, & Gold, 2002). Identification of mental health disorders among caregivers of children with asthma, therefore, is of clinical importance, both in terms of caregiver well-being and child asthma outcomes.
Caregiver Mental Health in Other Chronic Illnesses A number of studies have found that caregivers of chronically ill or disabled children generally experience a higher rate of depression and anxiety compared with caregivers of healthy children. In a meta-analysis investigating the prevalence of depression among mothers of children with developmental disabilities, results showed
C The Author 2015. Published by Oxford University Press on behalf of the Society of Pediatric Psychology. V
All rights reserved. For permissions, please e-mail: [email protected]
1
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Gemma Easter, PHD Candidate, Louise Sharpe, PHD, and Caroline J. Hunt, PHD
2
Comparisons With Normative Samples and Other Chronic Illnesses Studies investigating differences in anxious and depressive symptoms in caregivers of children with asthma versus the general population have shown mixed results. One study found that depressive symptoms among caregivers of children with asthma were higher than in the general population, with 33% of caregivers experiencing at least mild depressive symptoms (Szabo, Mezei, Kovari, & Cserhati, 2010). Another study reported prevalence rates of depressive symptoms among caregivers of asthma at 26.7% (Brown et al., 2006). This compares with reported 12-month prevalence rates of 9.5% in normative samples (Kessler, Chiu, Demler, Merikangas, & Walters, 2005). Another study found no differences in anxious symptoms between caregivers of children with asthma and the general population (Gupta, Mitchell, Giuffre, & Crawford, 2001). Similarly, studies investigating differences in anxious and depressive symptoms between caregivers of children with asthma and caregivers of children with other psychiatric or medical illnesses have, in general, found no differences (e.g., vs. chronic renal disease; Szabo et al., 2010; vs. congenital heart disease; Gupta et al., 2001; vs. cystic fibrosis; Yilmaz et al., 2008). While the above information is useful, these studies lack a nonclinical or healthy comparison group, which makes it difficult to estimate the degree to which anxious or depressive symptoms may differ between caregivers of children with and without asthma. For this reason, the current review will only include studies comparing anxious and depressive symptoms in caregivers of children with asthma and caregivers of healthy children, and exclude studies comparing symptoms with normative samples or caregivers of children with other medical or psychiatric diagnoses.
Moderating Influences on Caregiver Anxiety and Depression It is not only of interest to know whether caregivers have higher levels of anxiety and depressive symptoms than caregivers of healthy
children, but it is also important to know what factors might contribute to these higher symptom levels. Reviews of the literature have indicated a number of potential family influences on childhood asthma, although this research is still in its infancy. It has been suggested that family emotional characteristics, such as parental mental health and stress, are associated with more severe asthma (Lange et al., 2011). Similarly, asthma management, including adherence, and smoking status are thought to be important in the management and development of pediatric asthma (Cabana et al., 2004). Socioeconomic factors, ethnicity, and physiological factors, such as genetic influences, may all affect the onset of childhood asthma and its outcomes (see Kaugars et al., 2004). It is possible that these factors may be associated with both poor maternal mental health and more severe childhood asthma (see Celano, 2006). However, while a number of these potentially important factors have been systematically investigated in the literature on childhood asthma in general, they are not routinely reported in the literature investigating caregiver mental health and childhood asthma. As a result, in this review we have focused on potential methodological factors and child’s age as potential moderators of the relationship between childhood asthma and caregiver anxious and depressive symptoms. It might be expected that caregivers of younger children with asthma are more at risk of developing anxiety and depression compared with caregivers of older children. There are two main reasons for this. First, younger children typically have more severe symptoms, which tend to become better controlled as they age. Second, parents tend to bear more of the responsibility and burden of looking after younger children (McQuaid et al., 2003). For example, Streisand et al. (2005) found a negative association between parental stress and children’s age in a study on childhood diabetes. Similarly, the informant used to report asthma symptoms may affect the strength of the relationship between caregiver mental health and child asthma; however, the direction of this relationship is not clear. Wamboldt et al. (1998) found that parents with significant stressors tend to overreport their child’s internalizing symptoms. Therefore, it is possible that parents who are anxious may also interpret wheezing as asthma, and hence overreport a history of childhood asthma. On the other hand, a medically confirmed diagnosis of asthma may reflect greater severity of illness, and therefore, the relationship between caregiver mental health and child asthma may be stronger for studies relying on diagnostic measures than those that rely on parent-report measures, as the burden of care may be greater. For the same reason that children with severe symptoms are more likely to be seen in tertiary referral centers rather than the community, the site of recruitment, may also influence the degree to which anxious and depressive symptoms differ between groups of caregivers. It may be that anxious and depressive symptoms are greater in caregivers recruited from clinical samples versus community samples, as studies undertaken at a tertiary care center or specialized clinic may involve children who are likely to be most seriously affected by asthma, and therefore, their caregivers may be at greater risk for anxiety or depression.
Study Aims The aim of the current meta-analysis was twofold. The first aim was to assess whether anxious and depressive symptoms were greater among caregivers of children with asthma compared with caregivers of healthy children. The second aim was to investigate the following moderators: age of the child, informant of asthma diagnosis, and site of recruitment. We predicted that differences in symptoms
Downloaded from http://jpepsy.oxfordjournals.org/ at University of Nebraska-Lincoln Libraries on September 27, 2015
that mothers of children with developmental disabilities are at elevated risk of depression compared with mothers of healthy children (Singer, 2006). Similarly, a systematic review found that depressive symptoms among mothers of children with epilepsy was higher compared with mothers of children without epilepsy, with 50% of mothers of children with epilepsy estimated to be at risk of depression (Ferro & Speechley, 2009). Other studies have found that both anxious and depressive symptoms are higher in caregivers of children with cystic fibrosis (Yilmaz et al., 2008), psychotic disorders (RydeBrandt, 1990), and speech impairments (Rudolph, Rosanowski, Eysholdt, & Kummer, 2003) compared with caregivers of healthy children. A recent review found that stress was higher in parents of children with a range of chronic illnesses, including asthma, compared with parents of healthy children (Cousino & Hazen, 2013). Given the similarities in caring for children with asthma and other childhood chronic illnesses (Barlow & Ellard, 2006; Nuutila & Salantera, 2006), it would not be surprising if caregivers of children with asthma were particularly at risk for developing mental health problems compared with caregivers of healthy children. However, to date, we know of no review that has been conducted comparing anxious and depressive symptoms in caregivers of children with asthma and caregivers of healthy children. Despite this, there have been a number of individual studies that have compared caregivers of children with asthma with normative samples and caregivers of children with other chronic illnesses.
Easter, Sharpe, and Hunt
Anxiety and Depression in Caregivers of Children With Asthma
3
between the caregivers of children with asthma and caregivers of healthy children would be significantly greater when children were younger, when asthma had been medically diagnosed, and when children were recruited from a clinical setting.
2 because it included data for family members rather than mothers or primary caregivers, and 1 because the article was not written in English. Following this search process, 17 articles, reporting on 25 between-group comparisons, were retained for inclusion in the meta-analysis. These studies reported on the outcomes of 4,300 caregivers of children with asthma and 25,064 caregivers of healthy children. The process of study selection is shown in Figure 1.
Method Search Strategy
Inclusion and Exclusion Criteria To meet the inclusion criteria, a study needed to (a) involve caregivers of children or adolescents (18 years old) with an asthma diagnosis based on either a medically confirmed diagnosis or self-/parent-report measures, (b) use a measure of anxiety or depression (rather than a measure of “general distress” or “stress”) in terms of either a diagnosis or symptoms, for which information about the psychometric properties was available, (c) have a comparison group of caregivers of healthy children (i.e., children without asthma or any other medical or psychiatric diagnosis), (d) report statistical information that would allow for the calculation of an effect size, and (e) be written in English. Studies were also excluded if caregivers of children with asthma were compared with population norms on standardized measures.
Study Selection Seven hundred and thirty-eight unique articles were identified through the search strategy. The titles and abstracts of the articles were reviewed by one reviewer (G.E.), and a sample of 362 was reviewed by a second reviewer (C.H.), with good interrater reliability (j ¼ .83). Disagreements were resolved through consensus. Six hundred and ninety-two articles were excluded on the basis of the title and abstract search, as they did not measure anxious or depressive symptoms in primary caregivers of children with asthma compared with caregivers of healthy controls. Eight of these excluded articles reported results for caregivers of children with asthma versus caregivers of other chronic illnesses (e.g., epilepsy, diabetes) but not versus healthy controls The remaining 46 articles were full-text reviewed by two reviewers (G.E. and C.H.) for their relevance to the research question. The interrater reliability was good (j ¼ .81), and disagreements were resolved by consensus. Twenty-nine articles were excluded, as they did not meet full inclusion criteria. Articles were excluded for the following reasons: 14 articles were excluded because they did not use a measure of anxiety or depression, 7 for not providing enough information to calculate an effect size, 5 for not including a healthy control group,
Quality Ratings Articles were reviewed for quality using a modified version of the Quality Index Scale (QIS; Downs & Black, 1998; see Table I for outcomes of quality ratings). The Quality Index was initially developed to systematically rate the research quality of randomized and nonrandomized studies of health-care interventions. The Quality Index was modified to exclude assessment of items relating to intervention studies, including randomization, blinding, and withdrawals and dropouts, which reduced the original 27-item index to 15 items. This modified version was used in a systematic review of depressive symptoms among mothers of children with epilepsy (Ferro & Speechley, 2009). The QIS has good reliability and validity for measuring the methodological quality of health research (Downs & Black, 1998; Olivo et al., 2008; Sanderson, Tatt, & Higgins, 2007; Wang, Collet, Shapiro, & Ware, 2008). Items were scored either 0 (no/unable to determine) or 1 (yes), with a maximum score of 15. The items covered standard of reporting (0–7), external validity (0–3), internal validity (0–4), and study power (0–1), with higher scores indicating articles with higher methodological quality. The first author conducted the quality review on all of the articles. A selection of five articles was reviewed by the third author, with good interrater reliability (j ¼ .87). Any discrepancies were resolved by consensus. The overall mean QIS was 10.7 (SD ¼ 1.7) with scores ranging between 8 and 13 (out of a total score of 15). The mean subscale scores were 5.9 (SD ¼ 0.9) for reporting, 1.4 (SD ¼ 0.8) for external validity, and 3.4 (SD ¼ 0.7) for internal validity. Only one study (Leao et al., 2009) reported a formal sample size or power calculation.
Statistical Approach To determine whether anxiety and depressive symptoms differed among caregivers of children with asthma versus caregivers of healthy children, meta-analytic procedures were used. The following data were extracted by the first reviewer to answer the research questions: sample size and mean age of children in both the asthma and healthy control groups, informant type for asthma diagnosis, site of recruitment, study design, and data needed to compute effect sizes (e.g., mean and standard deviations of anxiety or depressive symptom measures or proportion of caregivers meeting a clinical cutoff score or diagnosis). Attempts were made to contact study authors for additional data as needed. Effect sizes were converted to Cohen’s d (Hedges & Olkin, 1985). For studies reporting means and standard deviations of anxiety and depressive symptom scores, Cohen’s d (the difference between the means of two groups, divided by the pooled standard deviation) was calculated. For studies reporting frequencies or proportions, data were converted into Cohen’s d. In studies where more than one assessment point was included (e.g., prospective studies), we included only the baseline scores. If both mother and father reports were provided, only mother-reported measures were used for comparison purposes because only two studies included separate data from fathers. We considered conducting analyses for those
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A literature search was conducted using the following databases: MEDLINE, PsycINFO, Cumulative Index to Nursing and Allied Health Literature, and Embase. The search was limited to articles published in a peer-reviewed journal and unpublished dissertations between January 1975 and February 2014. The following search terms were used to identify articles meeting the inclusion criteria. The first stem group search terms included “depression” or “depressive symptoms” or “anxiety” or “anxiety symptoms” or “psychological distress.” The second stem group included “mother$” or “maternal” or “caregiver” or “parent$.” The final stem group included “asthma.” Medical Subject Heading (MeSH) terms were exploded to broaden the search for relevant studies. The ancestry method, which involves reviewing the references of those articles included in the meta-analysis and any relevant reviews for other relevant articles not identified in the original search, was used to identify further studies.
4
Easter, Sharpe, and Hunt
Articles identiied with search strategy (n=738)
Articles excluded on the basis of their titles and abstracts (n=692) •
Articles reviewed in depth for relevance (n=46) Articles excluded due to methodological requirements (n=29) • • • • •
No validated measure of anxiety or depression (n=14) Not enough information to calculate effect size (n=7) No healthy control group (n=5) Information not available for primary caregiver (n=2) Articles not written in English (n=1)
Total articles included in the analysis (n=17)
Figure 1. Search and study selection process.
studies that included father data; however, they were insufficient to allow quantitative analyses. All analyses conducted were between groups, meaning a positive sign of d indicates that anxiety or depressive symptoms were greater for caregivers of children with asthma than caregivers of healthy children. Within each symptom variable (anxiety or depression) the mean weighted effect sizes (with withinsubjects effect sizes combined before averaging) were first calculated by a random-effects model because the studies’ effect sizes were not assumed to be drawn from a sample with a single true population effect size. Cohen’s d was interpreted based on the following recommended rules of thumb: 0.2 ¼ small, 0.5 ¼ medium, 0.8 ¼ large (Cohen, 1988). Together with the overall mean, we report the 95% confidence interval (CI), T (or tau, the estimated standard deviation of the true effect sizes), Q (a test for homogeneity of effect sizes across studies), and I2 (a measure of the magnitude of heterogeneity, or the percentage of the observed variance that is real rather than spurious). Subgroup analyses were conducted to examine whether potential moderator variables (informant type for asthma diagnosis and site of recruitment could account for the variability among effect sizes. These analyses used mixed-effect models, consisting of a randomeffects model within subgroups and a fixed effect model across subgroups, consistent with previously published studies (Koenig, Eagly, Mitchell, & Ristikari, 2011). Both models were calculated using the method of moments (Borenstein, 2009). A simple meta-regression
was used to assess the one continuous moderator, child’s age, to determine whether the mean age of participants in each study can account for variance in the effect size of that study. A fail safe N analysis was conducted to address and potential “file drawer” problem (Rosenthal, 1979), such that only positive results are published. Fail-safe N analyses estimate the number of studies that would need to have been conducted and not published before the reported positive results would become null. All analyses were conducted using Comprehensive Meta-Analysis (Version 2.0).
Results Study Characteristics There were 17 articles that were included in the meta-analysis, which reported the results of 25 between-group comparisons (herein referred to as studies). The additional comparisons were because eight of the articles included a measure of both depression and anxiety (see Table I for more details and References for citations of the included articles). The 17 articles reviewed were published over a 37-year period between 1977 and 2014. The articles reported on results for 4,300 caregivers of children with asthma and 25,064 caregivers of healthy children. Of the 17 unique articles reporting the results of 25 comparisons, 10 reported on depressive symptoms and 15 reported on
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• • • •
Anxiety or depression not measured in primary caregiver (n=248) Not asthma focused (n=211) No data available (n=152) No healthy control group (n=77) Not human research (n=4)
Longitudinal
Longitudinal
Cross-sectional
Cross-sectional
Cross-sectional
Cross-sectional
Cross-sectional
Davis (1977) (United Kingdom)
Feldman et al. (2011)
Guxens et al., (2014)
(The Netherlands) Kean et al. (2006) (United States)
Krommydas et al. (2002) (Greece)
Leao et al. (2009) (Brazil)
Ortega, Goodwin, McQuaid, &
Canino (2004) (United States) Ozkaya, Cetin, Ugurad, &
Longitudinal
Tu, Perreault, Seguin, &
g
Cross-sectional
Cross-sectional
Yilmaz et al. (2008) (Turkey)
Yuksel et al. (2007) (Turkey)
Clinical
Clinical
Community
Population-based cohort
Population-based cohort
75
62
50
115
1,109
8.4 (2.9) 7–16
8.1 (2.9)
13.3 (2.7) 8–18
1.4 (0)
7.6 (2.2) 4–11
5–12
Diagnosis
Diagnosis
Diagnosis
Parent report
Parent report
Parent report
Diagnosis
Parent report
Diagnosis
g
46
21
33
1,581
10,090
738e
32
662
90
1,466
160
70
50
4,557
288
101
5,079
N
9.1 (3.6) 7–15
8.8 (3.4)
13.5 (2.0) 9–17
1.4 (0)
7.5 (2.3) 4–11
5–12
7.8 6–9
5–12
4–15
8.2 (3.9)
4–17
2–11
4–8 4.9
6.0 (1.2)
12–18
14.8
6.5
10–25
17.7 (0.3)
