Objective: : Sociocultural factors have been implicated in affecting prevalence, incidence, and diagnosis of depression but previous studies have included heterogeneous ethnic populations. We studied the influence of cultural assimilation on the prevalence and presentation of depressive symptoms in elderly Japanese American men.
Method: : This analysis was based on 3,139 Japanese American men aged 71-93 years who were participants in the Honolulu-Asia Aging Study between 1991 and 1993. We created a Cultural Assimilation Scale (CAS) using 8 questions assessing the degree of Japanese identity and lifestyle compared to a Western one. Subjects were divided into tertiles of CAS score for analysis. Prevalence of depressive symptoms was measured using an 11-question version of the Centers for Epidemiologic Studies Depression Scale questionnaire, and presence of depressive symptoms was defined as score 9 or more.
Results: : Prevalent depressive symptoms did not reach a statistically significant association with CAS tertiles (Western, 10.8%; Mixed, 9.6%; and Japanese, 8.5%). However after adjusting for demographic, functional, and disease factors, the most culturally Japanese group had significantly lower odds for prevalent depressive symptoms, compared to the most Western group. Among the subset of subjects with a high-Centers for Epidemiologic Studies Depression Scale-11 score, there were no significant differences in both mean psychological scores and mean somatic scores between the three CAS groups.
Conclusions: : Prevalent depressive symptoms were significantly lower among elderly Japanese American men who were most culturally Japanese, compared to more westernized men. Improving knowledge and understanding about the pathogenesis of depression will have important public health implications.