INTRODUCTIONEpidemiological studies worldwide have consistently reported major depressive disorder (MDD) to be among the most common psychiatric disorders, with an estimated lifetime prevalence in the range of 12% to 16% in Western communities, (1)(2)(3)(4) and much lower in Asia, ranging between 3% and 6%.(5-7) MDD can be chronic or recurrent, consequently affecting and impacting individuals for many months, years or even decades. MDD is also associated with significant comorbidity, poor health and mortality.Certain sociodemographic risk factors, including age, gender and ethnicity, have frequently been associated with MDD. The prevalence of MDD is higher among women compared to men, (8)(9)(10) and is often 1.5-3 times higher among women than men. (11)(12)(13) Research has also shown that among women, depression is the leading cause of disease-related disability.(11) These findings have been reported in both clinical and general populations and remain evident, irrespective of where the research is conducted and how it is assessed. These gender differences are likely to be a result of a myriad of factors, including biological, social, demographic and/or psychological effects. Gender itself affects many aspects of psychopathology, including prevalence of disorders, expression of symptoms, course of illness, help-seeking behaviour and response to treatment. (14) Singapore is located off the Malaysian peninsula in Southeast Asia and has a resident population (including Singapore citizens and permanent residents) of 3.8 million people.(15) The Singapore Mental Health Study (SMHS) was a population-based epidemiological study that aimed to establish the prevalence of mental disorders among Singapore residents aged ≥ 18 years. Findings showed that MDD was the most prevalent mental disorder among those examined in the SMHS, which reported a lifetime prevalence of 5.8% and a 12-month prevalence of 2.2%. (6) Upon further analysis, the SMHS also found that the prevalence of MDD was significantly higher among women, Indians and those who were divorced/separated or widowed. Chronic physical comorbidities were also found to be present in approximately half of all respondents with MDD.(16) Given the high prevalence of MDD among the general adult Singapore population, combined with the significant treatment gap and likelihood of chronic physical comorbidities, the present study aimed to establish whether there were any gender-specific differences relating to the prevalence and correlates of MDD among the adult resident population in Singapore.
METHODSThe SMHS was a cross-sectional epidemiological survey among a representative household sample of Singapore citizens and permanent residents aged ≥ 18 years, who were fluent in English, Mandarin or Malay. Participants were randomly selected from an administrative database that maintains names