Perinatal mental health outcomes for people with intellectual disability: A data linkage study in New South Wales, Australia

OBJECTIVE: To describe perinatal mental health outcomes among people with intellectual disability giving birth in New South Wales, Australia. METHODS: This retrospective, descriptive cohort study included 30,257 people (2262 people with intellectual disability and 27,995 comparators without intellectual disability) aged 10+ years, discharged from New South Wales hospitals between 2002 and 2017 following a live singleton birth. We used administrative data from emergency departments, hospitals, ambulatory mental health services, Medicare-subsidised services and the Pharmaceutical Benefits Scheme. We defined the overall perinatal period as 140 days before to 365 days after birth. We also examined outcomes within four specific timeframes: 140 days to birth, 1-42, 43-90 and 91-365 days after birth. RESULTS: Across the overall perinatal period, people with intellectual disability who gave birth had greater risk of having at least one mental health emergency department presentation (risk ratio = 7.01 (5.78-8.50)), mental health hospital admission (risk ratio = 8.97 (7.54-10.67)), ambulatory mental health service contact (risk ratio = 5.55 (4.90-6.28)) and Medicare-subsidised mental health service contact (risk ratio = 1.99 (1.82-2.16)) than comparators. The most common diagnoses among people with intellectual disability were mood (12.6%; risk ratio = 3.83 (3.38-4.35)) and anxiety, stress-related and somatoform disorders (11.9%; risk ratio = 3.62 (3.19-4.12)). People with intellectual disability were more likely to be dispensed antipsychotics (risk ratio = 9.29 (7.74-11.16)), anxiolytics (risk ratio = 3.03 (2.44-3.76)), hypnotics/sedatives (risk ratio = 2.08 (1.55-2.78)), antidepressants (risk ratio = 2.30 (2.13-2.49)) and psychostimulants (risk ratio = 4.00 (2.03-7.89)). CONCLUSION: Our findings show elevated use of mental health services by people with intellectual disability in the perinatal period and underscore the need for accessible and adequately equipped acute and community-based mental health services.