Canadian Psychiatric Association
Association des psychiatres du Canada
Original Research
Perinatal Health of Women with Intellectual and Developmental Disabilities and Comorbid Mental Illness
The Canadian Journal of Psychiatry / La Revue Canadienne de Psychiatrie 2016, Vol. 61(11) 714-723 ª The Author(s) 2016 Reprints and permission: sagepub.com/journalsPermissions.nav DOI: 10.1177/0706743716649188 TheCJP.ca | LaRCP.ca
Sante´ pe´rinatale des femmes souffrant de de´ficiences intellectuelles et de´veloppementales et d’une maladie mentale comorbide
Hilary K. Brown, PhD1,2,3, Virginie Cobigo, PhD3,4, Yona Lunsky, PhD2,3,5, Cindy-Lee Dennis, PhD1,2, and Simone Vigod, MD, MSc, FRCPC1,2,3
Abstract Objective: Women with intellectual and developmental disabilities (IDD) have high rates of adverse perinatal outcomes. However, the perinatal health of women with co-occurring IDD and mental illness (dual diagnosis) is largely unknown. Our objectives were to 1) describe a cohort of women with dual diagnosis in terms of their social and health characteristics and 2) compare their risks for adverse maternal and neonatal outcomes to those of women with IDD only. Method: We conducted a population-based study using linked Ontario (Canada) health and social services administrative data to identify singleton obstetric deliveries to women with dual diagnosis (n ¼ 2080) and women with IDD only (n ¼ 1852; 2002–2012). Primary maternal outcomes were gestational diabetes, gestational hypertension, preeclampsia/eclampsia, and venous thromboembolism. Primary neonatal outcomes were preterm birth, small for gestational age, and large for gestational age. We also examined several secondary outcomes. Results: Women with dual diagnosis were more likely than women with IDD only to live in poor neighborhoods and to have prepregnancy health conditions; however, they had more frequent prenatal care. Infants born to women with dual diagnosis had increased risks for preterm birth (adjusted relative risk [aRR] 1.31, 95% confidence interval [CI] 1.08 to 1.59) and neonatal morbidity (aRR 1.35, 95% CI 1.03 to 1.76) compared with infants born to women with IDD only. All other primary and secondary outcomes were nonsignificant. Conclusions: Comorbid mental illness contributes little additional risk for adverse perinatal outcomes among women with IDD. Women with dual diagnosis and women with IDD alone require increased surveillance for maternal and neonatal complications. Abre´ge´ Objectif : Les femmes souffrant de de´ficiences intellectuelles et de´veloppementales (DID) ont des taux e´leve´s de re´sultats pe´rinataux inde´sirables. Cependant, la sante´ pe´rinatale des femmes souffrant de DID et de maladie mentale (diagnostic mixte) co-occurrentes est largement inconnue. Nos objectifs e´taient de : (1) de´crire une cohorte de femmes ayant un diagnostic mixte en ce qui concerne leurs caracte´ristiques de sante´ et sociales, et (2) comparer leurs risques de re´sultats maternels et ne´onataux inde´sirables avec ceux des femmes souffrant uniquement de DID.
1 2 3 4 5
Women’s College Research Institute, Toronto, Ontario, Canada University of Toronto, Toronto, Ontario, Canada Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada University of Ottawa, Ottawa, Ontario, Canada Centre for Addiction and Mental Health, Toronto, Ontario, Canada
Corresponding Author: Hilary K. Brown, PhD, Women’s College Hospital, 76 Grenville Street, Toronto, Ontario M5S 1B2, Canada. Email: [email protected]
La Revue Canadienne de Psychiatrie 61(11)
715
Me´thode : Nous avons mene´ une e´tude dans la population a` l’aide des donne´es administratives couple´es de sante´ et des services sociaux de l’Ontario (Canada) afin d’identifier les accouchements simples de femmes ayant un diagnostic mixte (N ¼ 2 080) et de femmes souffrant uniquement de DID (N ¼ 1 852) (2002-2012). Les principaux re´sultats maternels e´taient le diabe`te gestationnel, l’hypertension gestationnelle, la pre´e´clampsie/e´clampsie et la thrombo-embolie veineuse. Les principaux re´sultats ne´onataux e´taient la naissance pre´mature´e, l’hypotrophie ne´onatale, et l’hypertrophie ne´onatale. Nous avons aussi examine´ plusieurs re´sultats secondaires. Re´sultats : Les femmes ayant un diagnostic mixte e´taient plus susceptibles que les femmes souffrant uniquement de DID d’habiter des quartiers pauvres et d’avoir des e´tats de sante´ pre´-grossesse; toutefois, elles profitaient de soins pre´nataux plus fre´quents. Les be´be´s ne´s de femmes ayant un diagnostic mixte avaient des risques accrus de naissance pre´mature´e (RRc 1,31; IC a` 95 % 1,08 a` 1,59) et de morbidite´ ne´onatale (RRc 1,35; IC a` 95 % 1,03 a` 1,76) comparativement aux be´be´s ne´s de femmes souffrant uniquement de DID. Tous les autres re´sultats principaux et secondaires n’e´taient pas significatifs. Conclusions : La maladie mentale comorbide ajoute un modeste risque additionnel de re´sultats pe´rinataux inde´sirables chez les femmes souffrant de DID. Les femmes ayant un diagnostic mixte et les femmes souffrant uniquement de DID ne´cessitent une surveillance accrue des complications maternelles et ne´onatales. Keywords intellectual disability, developmental disabilities, mental health, pregnancy complications Intellectual and developmental disabilities (IDD) are neurodevelopmental disorders that are characterized by cognitive limitations and difficulties in practical, social, and conceptual domains.1 Affecting 1 in every 100 adults,2 IDD include fetal alcohol syndrome, autism, Down syndrome, and Fragile X syndrome.1 Historically, childbearing among women with IDD has been uncommon, likely because of sterilization and institutionalization practices of the early to mid-20th century.3 Recently, there has been an increase in the number of women with IDD receiving maternity services, suggesting a rising fertility rate.4 In Ontario in 2009, there were 20.3 live births for every 1000 women with IDD.5 Studies have shown that women with IDD, compared with those without IDD, are at increased risk for adverse maternal and neonatal outcomes.6-12 An Australian prospective cohort study found that women with IDD (N ¼ 54) were at increased risk for preeclampsia.6 Retrospective cohort studies from the United States8,9 found that women with IDD (N ¼ 340, N ¼ 703) were at increased risk for caesarean delivery, preterm birth, and perinatal mortality. A Swedish retrospective cohort study10,11 found that women with IDD (N ¼ 326) were at increased risk for perinatal mortality, preterm birth, and small for gestational age. In the largest population-based cohort study on this topic to date, we found that Ontario women with IDD (N ¼ 3932) were at increased risk for preeclampsia, venous thromboembolism, peripartum hemorrhage, severe obstetric morbidity, systemic maternal complications, preterm birth, small for gestational age, stillbirth, neonatal mortality, and neonatal morbidity.12 Nearly half of women with IDD have a mental illness.13 The co-occurrence of IDD and mental illness is sometimes labeled ‘‘dual diagnosis,’’ with the most common mental illness comorbidities being schizophrenia, depression, and anxiety.13 Health outcomes of adults with dual diagnosis are worse than those of adults with IDD only; for example, they are more likely to have diabetes mellitus and cardiovascular disease. 14,15 Reasons include higher rates of poverty,
substance use, and smoking among adults with dual diagnosis.13,16,17 No previous studies have examined the perinatal health of women with dual diagnosis. We hypothesized that they would have higher rates of social and health risk factors and increased risk for adverse maternal and neonatal outcomes compared with women with IDD only. The objectives of our study were to 1) describe a cohort of women with dual diagnosis in terms of their social and health characteristics and 2) compare their risks for adverse maternal and neonatal outcomes to those of women with IDD only.
Methods Study Design and Setting We undertook a population-based cohort study in Ontario, Canada. Ontario has 140 000 births each year and is Canada’s most populous province.18 All prenatal and obstetric services delivered in and outside of hospitals are free of charge to Ontario residents. The current study included obstetric deliveries with a conception date between April 1, 2002, and March 31, 2012. We obtained data from the Institute for Clinical Evaluative Sciences (ICES), a nonprofit, independent organization that holds data resulting from health care encounters of Ontario residents. ICES databases were linked using unique encoded identifiers and were analyzed at ICES. To identify study groups, we used the Canadian Institute for Health Information Discharge Abstract Database (hospitalizations), the Ontario Mental Health Reporting System (psychiatric hospitalizations), the National Ambulatory Care Reporting System (emergency department visits), the Ontario Health Insurance Plan database (primary care visits), and disability support information from the Ministry of Community and Social Services.19 The MOMBABY data set, which is derived from the Canadian Institute for
716
Health Information Discharge Abstract Database, was used to identify obstetric deliveries and to estimate conception date based on gestational age at delivery.20 The Registered Persons Database (birth date, postal code) and ICES databases described above were used to create outcomes and covariates. Diagnostic codes follow the Canadian Coding Standards for the International Statistical Classification of Diseases and Related Health Problems 10th Revision for hospital databases and physician billing claim codes for the Ontario Health Insurance Plan database. Procedural codes follow the Canadian Classification of Health Interventions. Sociodemographic information, primary diagnosis, physician billing claims, and procedures are reliable and valid.21
Study Sample We derived our sample of women with IDD from a cohort created using linked health and social services administrative data, in which all individuals aged 18 to 64 years with IDD in Ontario were identified as of April 1, 2009.19 Individuals were classified as having IDD if they had a relevant diagnostic code recorded in health administrative data since inception of each database (2 physician visits or 1 emergency department visit or hospitalization) or in disability support program documentation.19 Diagnoses included fetal alcohol syndrome, pervasive developmental disorders (e.g., autism), and chromosomal and autosomal anomalies (e.g., Down syndrome, Fragile X syndrome); a list of diagnostic codes is available elsewhere.22 The underlying conceptual definition of IDD, covering neurodevelopmental disorders marked by common limitations in cognitive and adaptive functioning, is consistent with policy23 and clinical1 definitions. For the current study, we identified, among women with IDD aged 18 to 49 years, all singleton obstetric deliveries of live-born or stillborn infants (>20 weeks’ gestational age) whose estimated conception date was between April 1, 2002, and March 31, 2012. This group was then divided into women with IDD only and women with IDD and a comorbid mental illness (‘‘dual diagnosis’’). Mental illness was determined by the presence of relevant diagnostic codes recorded in health administrative data (i.e., physician visits, emergency department visits, hospitalizations) in the 2 years preceding the estimated date of conception. Diagnoses included in the primary definition were schizophrenia or other psychotic disorders, bipolar disorder or major depression, other depression, anxiety disorders, personality disorders, adjustment disorders, and disorders of conduct or impulsivity (Supplementary Table S1).24,25 We also considered a more specific definition including only major mental illness (i.e., schizophrenia or other psychotic disorders, bipolar disorder, or major depression).26 We also had access to a cohort of women without IDD. They were divided into women with mental illness only (using the above definition) and women with neither IDD
The Canadian Journal of Psychiatry 61(11)
nor mental illness. We used these data for a sensitivity analysis.
Study Outcomes Primary outcomes were adverse maternal and neonatal outcomes that are elevated among women with IDD6-12 and women with mental illness27,28 and were hypothesized to be more common among women with dual diagnosis. Primary maternal outcomes were gestational diabetes, gestational hypertension, preeclampsia/eclampsia, and venous thromboembolism. Primary neonatal outcomes were preterm birth (
Association des psychiatres du Canada
Original Research
Perinatal Health of Women with Intellectual and Developmental Disabilities and Comorbid Mental Illness
The Canadian Journal of Psychiatry / La Revue Canadienne de Psychiatrie 2016, Vol. 61(11) 714-723 ª The Author(s) 2016 Reprints and permission: sagepub.com/journalsPermissions.nav DOI: 10.1177/0706743716649188 TheCJP.ca | LaRCP.ca
Sante´ pe´rinatale des femmes souffrant de de´ficiences intellectuelles et de´veloppementales et d’une maladie mentale comorbide
Hilary K. Brown, PhD1,2,3, Virginie Cobigo, PhD3,4, Yona Lunsky, PhD2,3,5, Cindy-Lee Dennis, PhD1,2, and Simone Vigod, MD, MSc, FRCPC1,2,3
Abstract Objective: Women with intellectual and developmental disabilities (IDD) have high rates of adverse perinatal outcomes. However, the perinatal health of women with co-occurring IDD and mental illness (dual diagnosis) is largely unknown. Our objectives were to 1) describe a cohort of women with dual diagnosis in terms of their social and health characteristics and 2) compare their risks for adverse maternal and neonatal outcomes to those of women with IDD only. Method: We conducted a population-based study using linked Ontario (Canada) health and social services administrative data to identify singleton obstetric deliveries to women with dual diagnosis (n ¼ 2080) and women with IDD only (n ¼ 1852; 2002–2012). Primary maternal outcomes were gestational diabetes, gestational hypertension, preeclampsia/eclampsia, and venous thromboembolism. Primary neonatal outcomes were preterm birth, small for gestational age, and large for gestational age. We also examined several secondary outcomes. Results: Women with dual diagnosis were more likely than women with IDD only to live in poor neighborhoods and to have prepregnancy health conditions; however, they had more frequent prenatal care. Infants born to women with dual diagnosis had increased risks for preterm birth (adjusted relative risk [aRR] 1.31, 95% confidence interval [CI] 1.08 to 1.59) and neonatal morbidity (aRR 1.35, 95% CI 1.03 to 1.76) compared with infants born to women with IDD only. All other primary and secondary outcomes were nonsignificant. Conclusions: Comorbid mental illness contributes little additional risk for adverse perinatal outcomes among women with IDD. Women with dual diagnosis and women with IDD alone require increased surveillance for maternal and neonatal complications. Abre´ge´ Objectif : Les femmes souffrant de de´ficiences intellectuelles et de´veloppementales (DID) ont des taux e´leve´s de re´sultats pe´rinataux inde´sirables. Cependant, la sante´ pe´rinatale des femmes souffrant de DID et de maladie mentale (diagnostic mixte) co-occurrentes est largement inconnue. Nos objectifs e´taient de : (1) de´crire une cohorte de femmes ayant un diagnostic mixte en ce qui concerne leurs caracte´ristiques de sante´ et sociales, et (2) comparer leurs risques de re´sultats maternels et ne´onataux inde´sirables avec ceux des femmes souffrant uniquement de DID.
1 2 3 4 5
Women’s College Research Institute, Toronto, Ontario, Canada University of Toronto, Toronto, Ontario, Canada Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada University of Ottawa, Ottawa, Ontario, Canada Centre for Addiction and Mental Health, Toronto, Ontario, Canada
Corresponding Author: Hilary K. Brown, PhD, Women’s College Hospital, 76 Grenville Street, Toronto, Ontario M5S 1B2, Canada. Email: [email protected]
La Revue Canadienne de Psychiatrie 61(11)
715
Me´thode : Nous avons mene´ une e´tude dans la population a` l’aide des donne´es administratives couple´es de sante´ et des services sociaux de l’Ontario (Canada) afin d’identifier les accouchements simples de femmes ayant un diagnostic mixte (N ¼ 2 080) et de femmes souffrant uniquement de DID (N ¼ 1 852) (2002-2012). Les principaux re´sultats maternels e´taient le diabe`te gestationnel, l’hypertension gestationnelle, la pre´e´clampsie/e´clampsie et la thrombo-embolie veineuse. Les principaux re´sultats ne´onataux e´taient la naissance pre´mature´e, l’hypotrophie ne´onatale, et l’hypertrophie ne´onatale. Nous avons aussi examine´ plusieurs re´sultats secondaires. Re´sultats : Les femmes ayant un diagnostic mixte e´taient plus susceptibles que les femmes souffrant uniquement de DID d’habiter des quartiers pauvres et d’avoir des e´tats de sante´ pre´-grossesse; toutefois, elles profitaient de soins pre´nataux plus fre´quents. Les be´be´s ne´s de femmes ayant un diagnostic mixte avaient des risques accrus de naissance pre´mature´e (RRc 1,31; IC a` 95 % 1,08 a` 1,59) et de morbidite´ ne´onatale (RRc 1,35; IC a` 95 % 1,03 a` 1,76) comparativement aux be´be´s ne´s de femmes souffrant uniquement de DID. Tous les autres re´sultats principaux et secondaires n’e´taient pas significatifs. Conclusions : La maladie mentale comorbide ajoute un modeste risque additionnel de re´sultats pe´rinataux inde´sirables chez les femmes souffrant de DID. Les femmes ayant un diagnostic mixte et les femmes souffrant uniquement de DID ne´cessitent une surveillance accrue des complications maternelles et ne´onatales. Keywords intellectual disability, developmental disabilities, mental health, pregnancy complications Intellectual and developmental disabilities (IDD) are neurodevelopmental disorders that are characterized by cognitive limitations and difficulties in practical, social, and conceptual domains.1 Affecting 1 in every 100 adults,2 IDD include fetal alcohol syndrome, autism, Down syndrome, and Fragile X syndrome.1 Historically, childbearing among women with IDD has been uncommon, likely because of sterilization and institutionalization practices of the early to mid-20th century.3 Recently, there has been an increase in the number of women with IDD receiving maternity services, suggesting a rising fertility rate.4 In Ontario in 2009, there were 20.3 live births for every 1000 women with IDD.5 Studies have shown that women with IDD, compared with those without IDD, are at increased risk for adverse maternal and neonatal outcomes.6-12 An Australian prospective cohort study found that women with IDD (N ¼ 54) were at increased risk for preeclampsia.6 Retrospective cohort studies from the United States8,9 found that women with IDD (N ¼ 340, N ¼ 703) were at increased risk for caesarean delivery, preterm birth, and perinatal mortality. A Swedish retrospective cohort study10,11 found that women with IDD (N ¼ 326) were at increased risk for perinatal mortality, preterm birth, and small for gestational age. In the largest population-based cohort study on this topic to date, we found that Ontario women with IDD (N ¼ 3932) were at increased risk for preeclampsia, venous thromboembolism, peripartum hemorrhage, severe obstetric morbidity, systemic maternal complications, preterm birth, small for gestational age, stillbirth, neonatal mortality, and neonatal morbidity.12 Nearly half of women with IDD have a mental illness.13 The co-occurrence of IDD and mental illness is sometimes labeled ‘‘dual diagnosis,’’ with the most common mental illness comorbidities being schizophrenia, depression, and anxiety.13 Health outcomes of adults with dual diagnosis are worse than those of adults with IDD only; for example, they are more likely to have diabetes mellitus and cardiovascular disease. 14,15 Reasons include higher rates of poverty,
substance use, and smoking among adults with dual diagnosis.13,16,17 No previous studies have examined the perinatal health of women with dual diagnosis. We hypothesized that they would have higher rates of social and health risk factors and increased risk for adverse maternal and neonatal outcomes compared with women with IDD only. The objectives of our study were to 1) describe a cohort of women with dual diagnosis in terms of their social and health characteristics and 2) compare their risks for adverse maternal and neonatal outcomes to those of women with IDD only.
Methods Study Design and Setting We undertook a population-based cohort study in Ontario, Canada. Ontario has 140 000 births each year and is Canada’s most populous province.18 All prenatal and obstetric services delivered in and outside of hospitals are free of charge to Ontario residents. The current study included obstetric deliveries with a conception date between April 1, 2002, and March 31, 2012. We obtained data from the Institute for Clinical Evaluative Sciences (ICES), a nonprofit, independent organization that holds data resulting from health care encounters of Ontario residents. ICES databases were linked using unique encoded identifiers and were analyzed at ICES. To identify study groups, we used the Canadian Institute for Health Information Discharge Abstract Database (hospitalizations), the Ontario Mental Health Reporting System (psychiatric hospitalizations), the National Ambulatory Care Reporting System (emergency department visits), the Ontario Health Insurance Plan database (primary care visits), and disability support information from the Ministry of Community and Social Services.19 The MOMBABY data set, which is derived from the Canadian Institute for
716
Health Information Discharge Abstract Database, was used to identify obstetric deliveries and to estimate conception date based on gestational age at delivery.20 The Registered Persons Database (birth date, postal code) and ICES databases described above were used to create outcomes and covariates. Diagnostic codes follow the Canadian Coding Standards for the International Statistical Classification of Diseases and Related Health Problems 10th Revision for hospital databases and physician billing claim codes for the Ontario Health Insurance Plan database. Procedural codes follow the Canadian Classification of Health Interventions. Sociodemographic information, primary diagnosis, physician billing claims, and procedures are reliable and valid.21
Study Sample We derived our sample of women with IDD from a cohort created using linked health and social services administrative data, in which all individuals aged 18 to 64 years with IDD in Ontario were identified as of April 1, 2009.19 Individuals were classified as having IDD if they had a relevant diagnostic code recorded in health administrative data since inception of each database (2 physician visits or 1 emergency department visit or hospitalization) or in disability support program documentation.19 Diagnoses included fetal alcohol syndrome, pervasive developmental disorders (e.g., autism), and chromosomal and autosomal anomalies (e.g., Down syndrome, Fragile X syndrome); a list of diagnostic codes is available elsewhere.22 The underlying conceptual definition of IDD, covering neurodevelopmental disorders marked by common limitations in cognitive and adaptive functioning, is consistent with policy23 and clinical1 definitions. For the current study, we identified, among women with IDD aged 18 to 49 years, all singleton obstetric deliveries of live-born or stillborn infants (>20 weeks’ gestational age) whose estimated conception date was between April 1, 2002, and March 31, 2012. This group was then divided into women with IDD only and women with IDD and a comorbid mental illness (‘‘dual diagnosis’’). Mental illness was determined by the presence of relevant diagnostic codes recorded in health administrative data (i.e., physician visits, emergency department visits, hospitalizations) in the 2 years preceding the estimated date of conception. Diagnoses included in the primary definition were schizophrenia or other psychotic disorders, bipolar disorder or major depression, other depression, anxiety disorders, personality disorders, adjustment disorders, and disorders of conduct or impulsivity (Supplementary Table S1).24,25 We also considered a more specific definition including only major mental illness (i.e., schizophrenia or other psychotic disorders, bipolar disorder, or major depression).26 We also had access to a cohort of women without IDD. They were divided into women with mental illness only (using the above definition) and women with neither IDD
The Canadian Journal of Psychiatry 61(11)
nor mental illness. We used these data for a sensitivity analysis.
Study Outcomes Primary outcomes were adverse maternal and neonatal outcomes that are elevated among women with IDD6-12 and women with mental illness27,28 and were hypothesized to be more common among women with dual diagnosis. Primary maternal outcomes were gestational diabetes, gestational hypertension, preeclampsia/eclampsia, and venous thromboembolism. Primary neonatal outcomes were preterm birth (
