Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành y học dành cho các bạn tham khảo đề tài: Simulation studies of age-specific lifetime major depression prevalence | Patten et al. BMC Psychiatry 2010 10 85 http 1471-244X 10 85 BMC Psychiatry RESEARCH ARTICLE Open Access Simulation studies of age-specific lifetime major depression prevalence Scott B Patten1 Lee Gordon-Brown2 Graham Meadows3 Abstract Background The lifetime prevalence LTP of Major Depressive Disorder MDD is the proportion of a population having met criteria for MDD during their life up to the time of assessment. Expectation holds that LTP should increase with age but this has not usually been observed. Instead LTP typically increases in the teenage years and twenties stabilizes in adulthood and then begins to decline in middle age. Proposed explanations for this pattern include a cohort effect increasing incidence in more recent birth cohorts recall failure and or differential mortality. Declining age-specific incidence may also play a role. Methods We used a simulation model to explore patterns of incidence recall and mortality in relation to the observed pattern of LTP. Lifetime prevalence estimates from the 2002 Canadian Community Health Survey Mental Health and Wellbeing CCHS were used for model validation and calibration. Results Incidence rates predicting realistic values for LTP in the 15-24 year age group where mortality is unlikely to substantially influence prevalence lead to excessive LTP later in life given reasonable assumptions about mortality and recall failure. This suggests that in the absence of cohort effects incidence rates decline with age. Differential mortality may make a contribution to the prevalence pattern but only in older age categories. Cohort effects can explain the observed pattern but only if recent birth cohorts have a much higher approximately 10fold greater risk and if incidence has increased with successive birth cohorts over the past 60-70 years. Conclusions The pattern of lifetime prevalence observed in cross-sectional epidemiologic studies seems most plausibly explained by incidence that declines .
