Prevalence and correlates of bipolar spectrum disorders in Singapore: Results from the 2016 Singapore Mental Health Study (SMHS 2016).

BACKGROUND

Prevalence estimates of Bipolar Spectrum Disorders (BSD) remain scant in Southeast Asia. This study aims to investigate the prevalence of BSD, its correlates with sociodemographic factors, and the associations between the BSD subgroups and clinical severity, impairment, and disability in Singapore.

METHODS

This study utilizes data gathered from the second Singapore Mental Health Study (SMHS)- a nationwide cross-sectional survey conducted between 2016 and 2018 (response rate: 69.5%). Respondents were randomly selected and administered, in a single visit, interviewer-led surveys of the World Health Organization Composite International Diagnostic Interview version 3.0 (CIDI 3.0) in their preferred language (i.e. Chinese, Malay, Tamil, or English). A total of 6126 residents completed the study.

RESULTS

The lifetime weighted prevalence of BSD, Bipolar I, II, and subthreshold bipolar disorder was 3.1%, 1.5%, 0.03%, and 1.6% respectively. A higher prevalence of Bipolar Disorders (BPD) was significantly associated with younger age, being divorced or separated, and being unemployed. Lifetime comorbidity of BSD with at least one other psychiatric or physical condition was 45% and 51% respectively. BSD was most comorbid with Obsessive Compulsive Disorder (psychiatric condition) and Chronic pain (physical condition).

LIMITATIONS: This study relies on self-report data which may be subject to unintended response biases leading to the under or over-reporting of results.

DISCUSSION: In addition to the high prevalence of BPD, there is also a concerning shift and increase in the proportion of those who experience severe symptoms of mania/hypomania and depression. Subthreshold bipolar disorder is found to be clinically significant and cross-culturally valid in a multi-cultural setting.