Depressive symptoms in Chinese-American subjects with cognitive impairment

Objectives: To compare the prevalence of depressive symptoms and frequency of antidepressant use between a group of elderly Chinese-American subjects with and without cognitive impairment and a group of matched white subjects. A secondary aim was to examine the clinical and demographic predictors of depressive symptoms across these groups.

Methods: The study was conducted at an academic neurology subspecialty clinic. This was a case-control study with 140 Chinese-American subjects and 140 demographically and cognitively matched white subjects. In each group, there were 48 cognitively normal and 92 cognitively impaired participants (49 with mild cognitive impairment, 43 with Alzheimer disease). The proportion of individuals with significant depressive symptoms, as indicated by a Geriatric Depression Scale score ≥6 of 15, and frequency of antidepressant use were compared across groups by using χ(2) analysis. Factors predicting depressive symptoms, including racial and diagnostic group, age, gender, Mini-Mental State Examination score, level of functional impairment, education level, and medical comorbidities, were assessed by using linear regression analysis.

Results: Significant depressive symptoms were more common in cognitively impaired Chinese-American (35%) than cognitively impaired white (15%; χ(2)[1] = 9.4; p = 0.004) subjects. Chinese-American subjects with cognitive impairment were less likely to be receiving treatment for depression (12%) than white subjects with cognitive impairment (37%; χ(2)[1] = 15.6; p = 0.002). Racial and diagnostic group, age, level of functional impairment, Mini-Mental State Examination score, and education level were all statistically significant independent predictors of Geriatric Depression Scale score.

Conclusions: Elderly Chinese-American subjects with cognitive impairment are at increased risk for unrecognized and untreated depressive symptoms compared with elderly white subjects with cognitive impairment. Education level may contribute to this risk or it may be a surrogate marker for other factors contributing to depressive symptoms in this group.