ORIGINAL ARTICLE

Suicidality in Chronic Pain: Predictors of Suicidal Ideation in Fibromyalgia Yolanda Tri~ nanes, MSc*; Alberto Gonzalez-Villar, MSc*; Claudio G omez-Perretta, † na, PhD* MD ; Marıa T. Carrillo-de-la-Pe~ *Department of Clinical Psychology and Psychobiology, University of Santiago de Compostela, Santiago de Compostela, Spain; †Research Foundation of La Fe Hospital, Valencia, Spain

& Abstract Objectives: Fibromyalgia (FM) has been associated with a higher prevalence of suicidal behavior. Nevertheless, much remains unknown about suicide risk factors for this chronic pain disorder. In the present study, the relationship of suicidal ideation in FM with a number of sociodemographic, clinical, and psychological variables was analyzed. Methods: One hundred seventeen women with Fibromyalgia were assessed. The procedure included the exploration of sleep problems (Pittsburgh Sleep Quality Index), depression (Beck Depression Inventory [BDI]), health-related quality of life (SF-36 and Fibromyalgia Impact Questionnaire), the core symptoms of FM (visual analogue scales), and algometry of tender points. Suicidal ideation was evaluated by item 9 of the BDI. Patients with presence vs. absence of suicidal ideation were compared in all the variables studied. Results: The prevalence of suicidal ideation among FM patients was 32.5%. Significant differences between patients with vs. without suicidal ideas emerged mainly for the various indices of depression. Patients with suicidal ideation also reported higher levels of anxiety, more day dysfunction due to sleepiness and more limitations due to emotional and physical problems. Logistic regression analysis revealed that

Address correspondence and reprint requests to: Marıa Teresa Carrillo~ a, PhD, Department of Clinical Psychology and Psychobiology. de-la-Pen  Marıa Sua rez Nu ~ ez, s/n. Campus Vida. 15782 Santiago de n Calle Xose Compostela. E-mail: [email protected]. Submitted: August 06, 2013; Revision accepted: January 11, 2014 DOI. 10.1111/papr.12186

© 2014 World Institute of Pain, 1530-7085/14/$15.00 Pain Practice, Volume , Issue , 2014 –

cognitive depression symptoms such as BDI Self-Blame cluster are the more closely related to suicide ideation. Conclusions: The presence of suicidal ideation in FM patients is closely related to comorbid depression, anxiety and to a higher impact of the disease in daily life. & Key Words: fibromyalgia, chronic pain, suicide risk, suicidal ideation, suicide prevention

INTRODUCTION Suicide is a major worldwide health problem, with a million deaths per year and an estimation of 1.5 million deaths annually for the next decade.1 Suicidal ideation (SI) is more common than suicide attempts (SA),2 and the latter occur 10 times more frequently than suicides.3 There are numerous risk factors for suicidal ideation and behavior, and usually several of them contribute to suicide in a complex manner. Among the most important risk factors are depression and other mental disorders, physical diseases, alcohol and drug abuse, and psychosocial stress, as well as other factors related to suicidality itself (ie, previous SI or SA, availability of means, and exposure to other suicides). Other distal factors such as genetics, personality, or neurobiological disturbances (ie, serotonin dysfunction and hypothalamic–pituitary axis hyperactivity) have also been pointed out.2,4 From the physical disorders that have been associated with suicide, the most noteworthy are cancer, HIV/AIDS, Huntington’s disease, multiple sclerosis, epilepsy, peptic ulcer, renal disease, spinal cord injury, systemic lupus erythematosus, and pain.2

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Chronic pain is a common condition with a prevalence of 37.3% in developed countries and 41.1% in developing countries.5 Several studies have underlined the relationship between suicidal behavior and chronic noncancer pain.2,6,7 In fact, clinical practice guidelines on the prevention of suicide recommend a special consideration to chronic pain patients as an important risk group.8–12 Fibromyalgia (FM) is a chronic pain syndrome characterized by the presence of generalized pain, tenderness, and other associated symptoms such as fatigue, insomnia, anxiety, depression, and a number of somatic complaints.13,14 Despite the high prevalence of fibromyalgia and its association with some of the abovementioned relevant risk factors for suicide (especially depression and chronic pain), studies on FM and suicide are scarce. A systematic review of suicide in chronic pain disorders found a prevalence of SI close to 20% and of SA between 5% and 14%.6 In addition, it has been reported that chronic pain patients have more than double the risk of suicide as compared with the general population. Factors for suicidality in chronic pain include characteristics of pain (type, intensity, and duration), insomnia, and psychological aspects such as hopelessness, desire of escaping from pain, catastrophizing, and problem-solving deficits. In that review,6 only 2 of the articles included studied FM or widespread pain, with contradictory results. In 1 of them, there were no differences in suicide risk between patients with FM, rheumatoid arthritis, low back pain, and a group of healthy women.15 In another, widespread body pain was associated with a higher risk of death by suicide, compared with pain-free individuals.16 In addition, a few studies have been published to date examining the relationship between chronic pain and suicide, and only 3 of them include a sample of patients with FM. Ratcliffe et al.17 investigated the presence of SI and SA in different painful conditions (migraine, back pain, arthritis, and fibromyalgia) using a community survey. They found that arthritis and FM were associated with SI and SA, but that this association disappeared after adjusting for the presence of comorbid mental disorders. These results highlight the important role of mental disorders in suicidal behavior in those pathologies. Unfortunately, this study did not take into account other clinical variables of interest. These findings have been replicated partially in a recent large cohort study, in which the associations between pain disorders and suicide death were reduced after controlling for concomitant psychiatric conditions; however,

significant associations remained for back pain, migraine, and psychogenic pain.18 Other study with FM patients, carried out by Calandre et al.,19 employed a survey focused on the existence of prior suicide attempts and their relationship with sociodemographic variables, life impact of FM, and risk of suicide. They found that 16.7% of patients with FM reported 1 to 3 previous SA with drug poisoning, the most frequent method. In their sample, suicidal behavior was associated with severity of the disease and the presence of pain, poor sleep quality, anxiety, and depression. Nevertheless, only 22.6% of patients returned the survey (low response rate). Two recent large cohort studies that analyzed mortality rates in Denmark20 and the United States21 reported significantly higher mortality by suicide in FM compared with the general population. One of them also compared osteoarthritis vs. FM, finding higher rates of mortality by suicide in the latter.21 Although these studies have evidenced a relationship between suicidality and FM, much remains unknown about which variables could be mediating the risk of suicide in patients with FM. Suicidality is a complex problem without a unique profile or clear course, and therefore, risk factors for suicide would depend upon the characteristics of specific populations or disorders. Thus, it may be interesting to investigate what specific variables may influence the risk of suicide in FM. As it has been pointed out, the existing studies have been more extensive (community surveys conducted in large samples) than intensive (thoroughly examination of clinical and psychological variables of the patients that may be related to suicide). To clarify the relationship between suicide and FM, this study included a complete assessment procedure that comprised a clinical interview was conducted, psychological testing and physical examination of tender points in a sample of fibromyalgia outpatients. The relationship between suicidal ideation and intent and clinical and psychological variables was studied to verify suicidal risk factors in fibromyalgia. The identification of these factors will facilitate detection and management of patients with FM at risk of death by suicide.

METHODS Participants One hundred seventeen FM female patients (age range: 22 to 80 years; mean age: 49.09 years, SD = 9.26 years)

Predictors of Suicidal Ideation in Fibromyalgia  3

previously diagnosed according to the American College of Rheumatology (ACR) 1990 criteria13 participated in the study.* Inclusion criteria were to have FM diagnosed and no other chronic pain disease or any disorder that could explain the principal symptoms of FM. The mean time from the first diagnosis of FM in this sample was 8.25 years (SD = 6.21). At the moment of the study, 23 patients (19.7%) did not take any medication in the 24 hours previous to the recording; 22 (18.8%) were under analgesic medication; 13 (11.1%) under anxiolytic drugs; 11 (9.4%) under antidepressant treatment; 3 (2.6%) were using anticonvulsants, and the rest followed a combined treatment for analgesics + antidepressant medication (6%) or anxiolytic + antidepressant treatment (14.5%) or other (17.9%). Written informed consent was obtained from all the patients before participation. The procedure was approved by the Ethics Committee of our University.

Depression Inventory (BDI).22 BDI is a 21-item selfreport scale of depressive symptoms that contains a single item for rating suicide (item 9; Table 1). This 4point ordinal question asks about the patient level of suicidal ideation (first and second response options) and intent (third and fourth response options). The BDI suicide item has good concurrent and predictive validity and has been proposed to be useful for both clinical practice and research purposes.23 In fact, it has been used in studies that analyzed risk factors associated to suicidality in general population24 and in chronic noncancer pain.25,26 Measures The following self-report questionnaires and scales were included in the study: 

Procedures Some of the patients were informed about the study by their clinicians, and if they agreed to participate, a first telephone contact took place. Other patients were recruited through FM associations. They were appointed for the clinical assessment session, conducted by a mental health professional and a nurse. Although all the patients had a previous diagnosis of FM, a confirmation was carried out following the ACR criteria (1990). In 2010, the ACR proposed an alternative method of FM diagnosis without tender point examination.14 Nevertheless, since this study is part of a wider investigation on biomarkers that followed the 1990 criteria, we used these latter. Apart from the examination of the 18 tender points by pressure algometry, the session included a broad clinical interview with questions concerning current medication, years since FM diagnosis, and other core symptoms of fibromyalgia. Sociodemographic variables included, among others, marital status, education, current work, and occupational status. In this session, a number of self-reported questionnaires (see Measures) were also administered. Patients were classified according to the presence vs. absence of SI, on the basis of their responses to Beck

*It is important to note that only 1 participant was over 70 (80 years). This participant was retained for the analyses because there was no difference in the variables of interest with the rest of the sample.



The Beck Depression Inventory assesses the degree of severity of depressed mood. BDI total score ranges from 0 to 63, and higher total scores indicate more severe depressive symptoms.22 To avoid inflating the relationship between BDI and SI, the item 9 was removed from the total score, as it has been carried out in several studies.27 Also, following the proposal of Grunebaum et al. (2005),28 3 factors were considered: Subjective Depression (sum of items 1, 2, 4, 12, 13, 14, 15, 17, 21), Self-Blame (items 3, 5, 6, 7, and 8), and Somatic Complaint (items 16, 18, and 19). The validated Spanish version of the BDI was used.29 The Pittsburgh Sleep Quality Index (PSQI) is a self-rated questionnaire which assesses sleep quality and dysfunction over a 1-month time interval.30 It is composed of 7 subscales that explore different aspects of sleep disturbance and that are rated from 0 (no difficulty) to 3 (maximum difficulty). Global PSQI score has a range of 0 to 21, and higher punctuations indicate worse sleep quality. The Spanish-validated version of the PSQI was used.31

Table 1. Suicide Item of the Beck Depression Inventory Suicidal ideation severity I do not have any thoughts of killing myself I have thoughts of killing myself, but I would not carry them out I would like to kill myself I would kill myself if I had the chance

Rating 0 1 2 3

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The Fibromyalgia Impact Questionnaire (FIQ) is a specific questionnaire to assess quality of life in patients with FM. The FIQ is a validated tool that reflects the overall effect of fibromyalgia on different functional areas such as the realization of daily activities or the accomplishment of job or housework.32 It also assesses the severity of symptoms, namely pain, fatigue, stiffness, quality of sleep, anxiety, and depression in the last week. The FIQ total score ranges from 0 to 100, and a higher value indicates greater impact of FM. The Spanish FIQ (S-FIQ) was applied.33 Short-Form 36 Health Survey (SF-36)34 is a generic instrument to assess quality of life. It is a multipurpose, short-form health survey with 36 items that yields an 8-scale profile of functional health and well-being: physical functioning, role physical, bodily pain, general health, vitality, social functioning, role emotional, and mental health. Each subscale ranges from 0 to 100, where 0 is the worst and 100 is the best status value. It also provides a self-evaluated health transition item, which is not used in scoring the scales nor in summary measures, but has been shown to be useful in estimating average changes in health status during the year prior to its administration. The validated Spanish version was employed.35 Visual analogue scales (VAS). They were created ad hoc to assess pain and key symptoms of FM (morning stiffness, fatigue, headache, quality of sleep, health state, depression). Each scale consisted of a 10-cm line from “no problem” (score 0) to “extreme problem” (score 10), where the participants had to mark the interference of each symptom or their state in the last month.

In addition, Pain Threshold and Tolerance at the 18 tender points were measured by a pressure algometer (Wagner Force One, Model FDI). Pressure pain threshold was defined as the minimum force applied that induces pain and pressure pain tolerance as the maximum pain-pressure value that was born at each point. These measures were assessed at each of the 18 specific tender point sites according to the ACR 1990 criteria for FM.13 A tender point was considered positive when the patient felt pain at pressure of 4 kg/cm2 or less. For each participant, the total count of positive tender point (tender point count), and mean pain-pressure threshold and tolerance for the 18 points were calculated.

Statistical Analysis First, descriptive analysis of the sociodemographic and clinical variables was performed. To clarify what variables are associated with suicidality, one-way ANOVAs to compare patients with FM with vs. without SI were performed for all the variables measured. Given the close association between depression and suicide, a binary logistic regression analysis was also performed (stepwise method, Wald statistic), taking into account the 3 subscales of the BDI, with the presence of SI as the dependent variable. All the statistical analyses were performed with SPSS version 11.5 (SPSS Inc, Chicago, IL, U.S.A.).

RESULTS Descriptive demographic and clinical characteristics of the sample are summarized in Table 2. The majority of the patients with FM were married women (86.3%) that graduated from primary (61.51%) or high school (20.5%). About 60% of them had a full-time job, and 16.7% of them were on leave or had work disability. Eighty-five percent of the women fulfilled the ACR 1990 criteria of having more than 11 tender points (the remaining 15% had a previous formal diagnosis of FM, more than 3 months of generalized pain but not fulfilled the ACR 1990 criterion of more than 11 tender points at study entry†). Mean values for pain threshold and tolerance were 2.85 and 3.54, respectively. The ratings in the VAS revealed that the most frequently reported symptoms are pain, morning stiffness, fatigue, and sleep problems. Concerning self-report scales, the data showed that patients with FM present a moderate level of depression (mean BDI score = 20.46), sleep dysfunction (mean total PSQI score = 13.70), and a severe impairment in different functional areas and well-being due to their health condition (total SF-36 score = 37.90). The mean FIQ score for the FM group is 62.94, which is in correspondence with the values obtained for FM in other clinical studies. In relation to suicide, 31 (26.5%) FM women reported suicidal ideation (rating 1 in item 9). Seven (6%) patients with FM manifested suicidal intent or desire, with rates 2 (n = 5) or 3 (n = 2) in item 9.

† The 1990 ACR criteria of having more than 11 tender points have received several objections: the minimum number of tender points is arbitrary and should be interpreted as a distress indicator more than a classification criteria.36,37 For this reason, we decided to retain all the patients for the statistical analyses.

Predictors of Suicidal Ideation in Fibromyalgia  5

Table 2. Demographic and Clinical Characteristics of the Total Sample (n = 117) Variables Education (%) Never studied Primary School High School University Marital Status (%) Single Married Divorced Widowed Occupation (%) Housewife Student Part-time job Full-time job (low qualification) (medium qualification) (high qualification) Employment status (%) Currently working Leave, disability Unemployed Never worked Retired VAS (cm) Pain Health state Morning stiffness Fatigue Depression Headache Quality of sleep

Frequency or Mean (SD)

0.90 61.50 20.50 17.10 6.00 86.30 6.00 1.70 25.60 0.90 11.10 31.60 17.10 13.70 60.20 16.70 5.60 3.70 13.90 7.01 6.94 7.92 7.71 5.18 4.86 7.42

(1.91) (2.31) (2.64) (1.98) (3.07) (3.18) (2.67)

Variables Algometry Pain threshold Pain tolerance Tender point count More than 11 tender points Depression BDI total score Quality of sleep (PSQI) Duration of Sleep Sleep Disturbance Sleep Latency Day Dysfunction due to Sleepiness Sleep Efficiency Overall Sleep Quality Need Meds to Sleep PSQI total Score Quality of life (SF-36) Health Transition Physical Functioning Role Physical Bodily Pain General Health Vitality Social Functioning Role Emotional Mental Health SF-36 total score FM Impact (FIQ) Physical impairment for daily activities Feel Good Work missed due to FM Interference of pain with work Pain Fatigue Not Feel Rested Stiffness Anxiety Depression FIQ total score

Frequency or Mean (SD)

2.85 (0.99) 3.54 (1.08) 14.94 (3.78) 85.50% 20.46 (9.79) 1.80 1.95 2.05 2.23 2.11 2.05 1.54 13.70

(1.14) (0.74) (1.17) (0.90) (1.18) (0.81) (1.46) (4.47)

34.70 40.48 32.23 23.96 49.39 23.42 43.48 59.94 49.39 37.90

(23.95) (20.45) (21.52) (17.92) (21.65) (18.01) (25.83) (25.86) (21.65) (14.76)

2.68 6.34 2.94 6.51 7.22 7.92 8.21 7.38 6.77 5.69 62.94

(2.00) (2.55) (3.16) (2.84) (2.23) (2.19) (2.01) (2.26) (2.87) (3.29) (15.81)

VAS, Visual Analogue Scale; BDI, Beck Depression Inventory; FIQ, Fibromyalgia Impact Questionnaire; SF-36, Short-Form 36 Health Survey; PSQI, Pittsburgh Sleep Quality Index; FM, Fibromyalgia.

Altogether, 32.5% of the patients with FM scored positively in BDI item 9. To clarify which of the variables under study were associated with the presence of SI, patients with FM who scored positively in BDI item 9 (n = 38) were compared with patients with FM that did not manifest suicidal ideation or desire (n = 79), against each of the sociodemographic, physical, and psychological variables considered. Table 3 presents only the differences that were found significant. As may be seen, the more significant differences between the groups emerged for the various indices of depression or psychological distress. Patients with SI presented higher scores in the following measures: BDI after removing suicide item (F(1,116) = 28.29; P < 0.001); the visual analogue scale that assessed mood state (depression) in the last month (F(1,116) = 15.87;

P < 0.001); and FIQ item 10, which refers to depression in the last week (F(1,116) = 24.41; P < 0.001). In addition, patients with suicidal ideation reported more anxiety (FIQ item 9; F(1,116) = 6.91; P < 0.01) and more day dysfunction due to sleepiness (F(1,116) = 4.94; P < 0.05), although the global quality of sleep index (PSQI) did not differ between groups. In relation to quality of life, patients with SI obtained worse scores in the SF-36 subscales Physical role (F(1,116) = 4.70; P < 0.05) and Emotional role (F(1,116) = 5.68; P < 0.05). They also obtained higher FIQ total scores, which may reveal a perceived higher interference of their disease in daily activities (F(1,116) = 9.04; P < 0.01). From the sociodemographic variables considered, no difference between patients with vs. without SI was found significant. Given the close association between depression and suicide, the specific depressive symptom clusters related

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Table 3. Clinical and Psychological Variables that Differentiate Between FM Patients with vs. without Suicidal Ideation Variables*

FM patients with SI (n = 38)

FM patients without SI (n = 79)

6.67 (2.93) 25.71 (9.70) 7.62 (2.89)

Depression VAS depression BDI total score (minus item 9) FIQ-depression item Impact of the Disease FIQ total score SF-36 physical role SF-36 emotional role Sleep PSQI day dysfunction Anxiety FIQ-anxiety item

F

P

4.40 (2.86) 17.01 (7.51) 4.71 (3.04)

15.87 28.29 24.41

< 0.001 < 0.001 < 0.001

68.81 (16.38) 26.01 (23.27) 51.62 (23.80)

59.79 (14.57) 35.18 (20.12) 63.78 (26.00)

9.04 4.70 5.68

< 0.01 < 0.05 < 0.05

2.50 (0.77)

2.10 (0.93)

4.94

< 0.05

7.74 (2.66)

6.28 (2.86)

6.91

< 0.01

SI, suicidal ideation; VAS, Visual Analogue Scale; BDI, Beck Depression Inventory; FIQ, Fibromyalgia Impact Questionnaire; SF-36, Short-Form 36 Health Survey; PSQI, Pittsburgh Sleep Quality Index; FM, Fibromyalgia. Patients were categorized as ideators (with SI) or nonideators (without SI) according to the BDI suicide item. *Values are means (standard deviations).

to SI were analyzed. To this end, a binary logistic regression analysis on the presence of suicidal ideation was performed taking into account 3 subscales of the BDI previously reported28 (Subjective Depression, Selfblame, and Somatic Complaint). The model allowed a 75.2% of correct classifications of patients who belong to the group characterized by SI (Chi-Square = 19.34; P < 0.001), although the proportion of variance explained was only moderate (Nagelkerke r2 = 0.21) and also the percentage for the initial (null) model was 67.5%. The only significant variable retained in the equation was self-blame (B = 0.31; P < 0.001).

DISCUSSION Although there is growing evidence on the association of suicide and chronic pain conditions, suicidality among patients with FM has not been widely studied. Existing studies have provided some data about the association between suicidal behavior and fibromyalgia, but little attention has been devoted to the specific risk factors that may underline suicide ideas or behaviors in these patients. In the current study, the prevalence of SI in patients with FM was 32.5%, higher than the one found in a systematic review of studies in chronic pain patients (about 20%),6 but lower than the 40.3% reported in a chronic pain sample receiving opioid therapy.38 The rate found in our sample is much higher than the average for the general population in our context. The European Study of the Epidemiology of Mental Disorders (ESEMED) conducted in 6 European countries found a lifetime prevalence of SI of 7.8%, being of 4.4% in Spain.39 In other study that also used item 9 of the BDI,

they found that 2.3% of a Spanish sample of the general population had some degree of suicidal ideation.24 Most of our patients with FM reported only passive suicide ideas, that is, without desire or intent to commit it. Nevertheless, given that suicidality may be considered a continuum,40,41 early detection of individuals with suicide ideation is very important for prevention purposes. In fact, Fisher et al.25 found that rates of completed suicide were higher among chronic pain patients who reported suicidal intent. The present results clearly suggest that depression is one of the most important risk factor for suicidal ideation in patients with FM. Depression is a frequent comorbid disorder in FM, as in other chronic pain conditions.7 Consistently with other studies, the different measures of depression (BDI total score, FIQ-depression subscale, VAS for depression) were significantly higher for FM patients with suicidal ideation.17,42,43 The role of depression increasing suicidal ideation does not appear to be unique in patients with fibromyalgia and has been found in other chronic pain disorders, such as migraine, chronic fatigue syndrome, or bowel disorder.6,44–46 In this report, we tried to clarify what aspects of depression are more associated with risk of suicide in FM. Following Grunebaum et al.,28 the BDI was decomposed into 3 symptom clusters: Subjective Depression; Self-Blame; and Somatic Complaint. The binary logistic regression analysis showed that SelfBlame was the most relevant factor. This factor includes items concerning sense of failure, guilt, feeling of punishment, sense of disappointment, and self-criticism. Thus, it seems that patients with higher scores in this dimension are especially vulnerable to suicidal behavior.

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As in patients with major depression, cognitive distortions related to self-punitive thinking seem to be crucial in suicidality, even more important than sadness or the somatic aspects of depression. Self-blame partially overlaps with the DSM-IV melancholic subtype of depression, which has been associated with higher lethality of suicide methods compared with nonmelancholic depression.47 Moreover, the Self-blame factor correlated positively with impulsivity, hostility, and aggression.28 In this study, anxiety was also found to be higher in patients with SI. Anxiety has been pointed out as a relevant factor in suicidality in FM19 and other chronic pain conditions.6 Although studies on suicidality in chronic pain have suggested that some kind of pain patterns may be a risk factor for suicide, this study did not find any difference between suicide ideators and nonideators in any of the pain-related variables. Patients with suicide ideas did not report more severity of their pain sensations nor obtained higher scores in objective measures of pain threshold or tolerance. Some previous studies that examined the influence of pain intensity in suicidality have shown mixed results.6,18,19 Poor sleep quality is a frequent problem in patients with FM 48–50, and sleep disorders have being suggested as risk factors for suicide.50,51 In this sample, only significant differences for the index of day dysfunction due to sleepiness were found, but not in overall sleep quality or the other dimensions assessed by the PSQI. These findings are partially consistent with previous research showing a higher probability of suicidal ideation in chronic pain patients with insomnia and concomitant day dysfunction.6 Calandre et al.19 reported a positive correlation between poor sleep quality and suicide risk in patients with FM pain. The fact that important symptoms such as pain, sleep problems, or fatigue, among others, did not appear as contributing factors to suicide ideation in this study may have various explanations. It may be that physical status is not related to suicidality or that the key factor is the perceived interference of that status in daily life. Due to the reciprocal relationship between depression and chronic physical problems, it is also possible that those symptoms contribute indirectly to suicide ideation. Alternatively, the results could be explained by a “ceiling effect”, that is, high severity levels in these symptoms may affect their discriminatory power. In the present study, an increased perception of the impact of the disease in daily activities, job, or house-

work was associated with the presence of suicidal ideation. This result is similar to the previously reported by Calandre et al. (2011) who found higher total FIQ scores in patients with FM with previous suicide attempts and a positive correlation of the FIQ with the Plutchik suicide risk scale.19 The present report also found higher role limitations due to physical health and emotional problems, measured with the SF-36, in the patients with FM with suicidal ideation. Thus, the sense of culpability about the own illness along with the perception of its interference in one’s daily life may determine the patient’s feeling of being a burden to others, and this feeling may be a key factor in suicidal ideation. In fact, other recent studies with chronic pain patients have also underlined the crucial role of perceived burdensomeness to understand suicidal ideation in chronic pain patients.52–54 Self-perception of being a burden on others is also a key element of the interpersonal theory of suicide, a recently introduced framework.55 This theory states the hypothesis that passive suicidal thoughts could drift into an active desire for suicide by the simultaneous presence of perceived burdensomeness, thwarted need to belong, and hopelessness about those states. Moreover, the capability to engage in suicidal behavior may be triggered by repeated exposure to physical pain experiences causing increased pain tolerance. Thus, according to this theoretical framework, perceived burdensomeness and habituation to pain could be crucial factors in the higher suicidality (either ideation or attempts) found in chronic pain disorders. Interestingly, no significant differences were found between patients with FM with and without SI in the demographic variables. Although it has been suggested that suicide rates are higher in unemployed people in the general population,2 the present study did not find that employment status is associated with suicidal ideation. This association seems to be complex as mental illness may contribute, in part, to increase the risk of both unemployment and suicide.2 In the case of FM, the higher presence of sick leave or unemployment may be interpreted as a psychosocial stressor that could increase the burden of the disease, but our data suggest that the decisive factor in suicidal ideation in FM seems to be the presence of psychological distress. In fact, it has been suggested that demographic variables are less associated with suicidality in chronic pain patients.27 The limitations of this study highlight the assessment of suicidal ideation by only 1 question, the BDI suicide item. However, this item has shown to be a valid method

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to assess suicidal ideation and has been largely employed in studies that investigate risk factors in chronic pain samples and in the general population. Moreover, this study did not consider some variables such as family history of mental illness or trauma history, which are risk factors associated with suicide. An additional limitation is the cross-sectional design of the study, which did not allow us to establish causal relationships, and points to the need of conducting longitudinal studies with patients with fibromyalgia. To our knowledge, this study is one of only a few that have attempted to better understand the relationship between FM and suicidal thoughts and behaviors. The main strength of it is the combination of psychological and physical indices (pressure algometry as a pain evoked measure). In conclusion, this study, which includes clinical variables, physical examination of tender points, and psychological testing, suggests that one of the most relevant risk factors for suicide in patients with FM is depression. Patients who present cognitive distortions related to self-blame and self-punitive thinking seem to be particularly vulnerable and should be the target for suicide prevention. Although some manifestations of the illness are not more severe in the subgroup of patients with suicidal ideas, those patients perceived a worse quality of life and more interference of their disease in daily activities. Other aspects related to suicidal ideation were anxiety and day dysfunction due to sleep problems. Patients with fibromyalgia patients, especially those with comorbid depression, are an at-risk group for suicide and should be a target of suicide prevention. Programs to modify cognitive distortions, such as cognitive behavioral therapy, could play an important role in suicide prevention. More research is required to identify factors that may be predictors of suicidal ideation in fibromyalgia. The understanding of the biopsychosocial nature of pain in this disease and the study of other psychological variables, such as catastrophizing, could help to clarify the relationship between suicide and FM.

ACKNOWLEDGEMENTS  The authors would like to thank Dr. Marıa AlvarezAriza and Dr. Gerardo Atienza for helpful comments on the article. We also thank Dr. Antonio Rial-Boubeta for his assistance with statistical analysis. This work was supported by Spanish Ministry of Science and Innovation (ref PSI2009-14555).

REFERENCES 1. World Health Organization. WHO mortality database. http://www.whoint/healthinfo/morttables/en/ (accessed May 21, 2013). 2. Hawton K, van Heeringen K. Suicide. Lancet. 2009;373:1372–1381. 3. Nock MK, Borges G, Bromet EJ, et al. Cross-national prevalence and risk factors for suicidal ideation, plans and attempts. Br J Psychiatry. 2008;192:98–105. 4. McLean J, Maxwell M, Platt S, Harris F, Jepson R. Risk and Protective Factors for Suicide and Suicidal Behaviour: A Literature Review. Edinburgh: Scottish Government Social Research; 2008. 5. Tsang A, Von Korff M, Lee S, et al. Common chronic pain conditions in developed and developing countries: gender and age differences and comorbidity with depression-anxiety disorders. J Pain. 2008;9:883–891. 6. Tang NK, Crane C. Suicidality in chronic pain: a review of the prevalence, risk factors and psychological links. Psychol Med. 2006;36:575–586. 7. Fishbain DA. The association of chronic pain and suicide. Semin Clin Neuropsychiatry. 1999;4:221–227. 8. Magellan Behavioral Health. Clinical Practice Guideline for Assessing and Managing the Suicidal Patient. 6/08 v.2. Maryland Heights, MO: Magellan Health Services; 2008. 9. Wasserman D, Rihmer Z, Rujescu D, et al. The European Psychiatric Association (EPA) guidance on suicide treatment and prevention. Eur Psychiatry. 2011;14:113– 136. 10. National Collaborating Centre for Mental Health. Self-harm. The Short-term Physical and Psychological Management and Secondary Prevention of Self-harm in Primary and Secondary Care. National Clinical Practice Guideline. London: National Institute for Clinical Excellence; 2004. 11. Grupo de trabajo de la Guıa de Pr actica Clınica de Prevenci on y Tratamiento de la Conducta Suicida. Guıa de Pr actica Clınica de Prevenci on y Tratamiento de la Conducta Suicida. Madrid: Ministerio de Sanidad, Polıtica Social e Igualdad; 2012. 12. National Collaborating Centre for Mental Health. Selfharm: Longer-term Management. National Clinical Practice Guideline. London: National Institute for Clinical Excellence; 2011. 13. Wolfe F, Smythe HA, Yunus MB, et al. The American College of Rheumatology 1990 Criteria for the Classification of Fibromyalgia. Report of the Multicenter Criteria Committee. Arthritis Rheum 1990;33:160–172. 14. Wolfe F, Clauw D, Fitzcharles MA, et al. The American College of Rheumatology preliminary diagnostic criteria for fibromyalgia and measurement of symptom severity. Arthritis Care Res (Hoboken). 2010;62:600–610. 15. Amir M, Neumann L, Bor O, et al. Coping styles, anger, social support, and suicide risk of women with fibromyalgia syndrome. J Musculoskelet Pain. 2000;8:7–20.

Predictors of Suicidal Ideation in Fibromyalgia  9

16. Macfarlane GJ, McBeth J, Silman AJ. Widespread body pain and mortality: prospective population based study. BMJ. 2001;323:1–5. 17. Ratcliffe GE, Enns MW, Belik SL, Sareen J. Chronic pain conditions and suicidal ideation and suicidal attempts: an epidemiological perspective. Clin J Pain. 2008;24:204–210. 18. Ilgen MA, Kleinberg F, Ignacio RV, et al. Noncancer pain conditions and risk of suicide. JAMA Psychiatry. 2013;70:692–697. 19. Calandre EP, Vilchez JS, Molina-Barea R, et al. Suicide attempts and risk of suicide in patients with fibromyalgia: a survey in Spanish patients. Rheumatology (Oxford). 2011;50:1889–1893. 20. Dreyer L, Kendall S, Daneskiøld-Samsoe B, Bartels EM, Bliddal H. Mortality in a cohort of Danish patients with fibromyalgia: increased frequency of suicide. Arthritis Rheum. 2010;62:3101–3108. 21. Wolfe F, Hassett AL, Walitt B, Michaud K. Mortality in fibromyalgia: a study of 8,186 patients over thirty-five years. Arthritis Care Res (Hoboken). 2011;63:94–101. 22. Beck AT, Steer RA. Manual for Beck Depression Inventory. San Antonio, TX: Psychological Corporation; 1987. 23. Brown GK. A Review of Suicide Assessment Measures for Intervention Research With Adults and Older Adults. Rockville, MD: National Institute of Mental Health; 2002. 24. Casey PR, Dunn G, Kelly BD, et al. Factors associated with suicidal ideation in the general population: five-centre analysis from the ODIN study. Br J Psychiatry. 2006;189:410– 415. 25. Fisher BJ, Haythornthwaite JA, Heinberg LJ, Clark M, Reed J. Suicidal intent in patients with chronic pain. Pain. 2001;89:199–206. 26. Smith MT, Perlis ML, Haythornthwaite JA. Suicidal ideation in outpatients with chronic musculoskeletal pain: an exploratory study of the role of sleep onset insomnia and pain intensity. Clin J Pain. 2004;20:111–118. 27. Smith MT, Edwards RR, Robinson RC, Dworkin RH. Suicidal ideation, plans, and attempts in chronic pain patients: factors associated with increased risk. Pain. 2004;111:201– 208. 28. Grunebaum MF, Keilp J, Li S, et al. Symptom components of standard depression scales and past suicidal behavior. J Affect Disord. 2005;87:73–82. 29. Sanz J, Vazquez C. Fiabilidad, validez y datos normativos del Inventario para la Depresi on de Beck. Psicothema. 1998;2:303–318. 30. Buysse DJ, Charles F, Reynolds TH, Berman SR, Kupfer DJ. The Pittsburgh sleep quality index: a new instrument for psychiatric practice and research. Psychiatry Res. 1989;28:193–213. 31. Macıas JA, Royuela R. La versi on espa~ nola del Indice de Calidad de Sue~ no de Pittsburgh. Inf Psiquiatr. 1996; 146:465–472. 32. Bennett R. The Fibromyalgia Impact Questionnaire (FIQ): a review of its development, current version, operating

characteristics and uses. Clin Exp Rheumatol. 2005;23:S154– S162. 33. Monterde S, Salvata I, Montulla S, Fern andez-Ballart J. Validaci on de la versi on espa~ nola del fibromyalgiam impact questionnaire. Rev Esp Reumatol. 2004;31:507–513. 34. Ware JE. SF-36 health survey update. Spine. 2000;25:3130–3139. 35. Alonso J, Prieto L, Ant o JM. The Spanish version of the SF-36 health survey (the SF-36 health questionnaire): an instrument for measuring clinical results. Med Clin (Barc). 1995;104:771–776. 36. Wolfe F. The relation between tender points and fibromyalgia symptom variables: evidence that fibromyalgia is not a discrete disorder in the clinic. Ann Rheum Dis. 1997;56:268–271. 37. Schochat T, Croft P, Raspe H. The epidemiology of fibromyalgia. Workshop of the Standing Committee on Epidemiology European League Against Rheumatism (EULAR), Bad S€ ackingen, 19–21 November 1992. Br J Rheumatol. 1994;33:783–786. 38. Saffier K, Colombo C, Brown D, Mundt MP, Fleming MF. Addiction severity index in a chronic pain sample receiving opioid therapy. J Subst Abuse Treat. 2007;33:303– 311. 39. Bernal M, Haro JM, Bernert S, et al. Risk factors for suicidality in Europe: results from the ESEMED study. J Affect Disord. 2007;101:27–34. 40. Silverman MM, Berman AL, Sanddal MD, O’Carroll PW, Joiner TE. Rebuilding the tower of babel: a revised nomenclature for the study of suicide and suicidal behaviors. Part 1: background, rationale, and methodology. Suicide Life Threat Behav. 2007;37:248–263. 41. Silverman MM, Berman AL, Sanddal MD, O’Carroll PW, Joiner TE. Rebuilding the tower of babel: a revised nomenclature for the study of suicide and suicidal behaviors. Part 2: suicide-related ideations, communications, and behaviors. Suicide Life Threat Behav. 2007;37:264–277. 42. Calandre EP, Garcia-Carrillo J, Garcia-Leiva JM, et al. Subgrouping patients with fibromyalgia according to the results of the fibromyalgia impact questionnaire: a replication study. Rheumatol Int. 2011;31:1555–1559. 43. Gadalla T. Association of comorbid mood disorders and chronic illness with disability and quality of life in Ontario, Canada. Chronic Dis Can. 2008;28:148–154. 44. Breslau N. Migraine, suicidal ideation, and suicide attempts. Neurology. 1992;42:392–395. 45. Magni G, Rigatti-Luchini S, Fracca F, Merskey H. Suicidality in chronic abdominal pain: an analysis of the Hispanic Health and Nutrition Examination Survey (HHANES). Pain. 1998;76:137–144. 46. Keilp JG, Grunebaum MF, Gorlyn M, et al. Suicidal ideation and the subjective aspects of depression. J Affect Disord. 2012;140:75–81. 47. Grunebaum MF, Galfalvy HC, Oquendo MA, Burke AK, Mann JJ. Melancholia and the probability and lethality of suicide attempts. Br J Psychiatry. 2004;184:534–535.

10 

~ TRINANES ET AL.

48. Bjørngaard JH, Bjerkeset O, Romundstad P, Gunnell D. Sleeping problems and suicide in 75,000 Norwegian adults: a 20 year follow-up of the HUNT I study. Sleep. 2011;34:1155–1159. 49. Goodwin RD, Marusic A. Association between short sleep and suicidal ideation and suicide attempt among adults in the general population. Sleep. 2008;31:1097–1101. 50. Ulus Y, Akyol Y, Tander B, et al. Sleep quality in fibromyalgia and rheumatoid arthritis: associations with pain, fatigue, depression, and disease activity. Clin Exp Rheumatol. 2011;29:S92–S96. 51. Osorio CD, Gallinaro AL, Lorenzi-Filho G, Lage LV. Sleep quality in patients with fibromyalgia using the Pittsburgh Sleep Quality Index. J Rheumatol. 2006;33:1863– 1865.

52. Kowal J, Wilson KG, McWilliams LA, Peloquin K, Duong D. Self-perceived burden in chronic pain: relevance, prevalence, and predictors. Pain. 2012;153:1735–1741. 53. Kanzler KE, Bryan CJ, McGeary DD, Morrow CE. Suicidal ideation and perceived burdensomeness in patients with chronic pain. Pain Pract. 2012;12:602–609. 54. Fishbain DA, Bruns D, Meyer LJ, et al. Exploration of the relationship between disability perception, preference for death over disability, and suicidality in patients with acute and chronic pain. Pain Med. 2012;13:552–561. 55. Van Orden KA, Witte TK, Cukrowicz KC, et al. The interpersonal theory of suicide. Psychol Rev. 2010;117:575– 600.