BACKGROUND: Two recent surveys of depression among Chinese elderly people sampled different populations, used different case ascertainment methods and resulted in a seven-fold difference in prevalence rates. The present study was conducted to compare prevalence rates obtained with two commonly used methods in the same population, and to examine the risk factors for depression.
METHODS: The target population included all residents aged 65 years and over in a rural Chinese community. Participants were interviewed for demographic and medical information, examined by a neurologist and administered Chinese versions of the Geriatric Depression Scale-Short Form (GDS-S), the Cognitive Abilities Screening Instrument (CASI) and an Activities of Daily Living (ADL) form. Individuals who screened positive on the GDS-S were also interviewed by a psychiatrist for diagnosis according to the DSM-III-R criteria.
RESULTS: Among the 1313 participants, 26% screened positive on the GDS-S and 13% were diagnosed as having a depressive disorder, including 6.1% with major depression. Individuals with depressive disorders were more likely to have poor ADL scores, lower CASI scores, and chronic physical illnesses. They were also more likely to be female, older, illiterate and without a spouse, but adding these variables did not increase the overall association with the GDS-S score.
CONCLUSIONS: Depression was quite common in this Chinese rural geriatric population. The prevalence rate was twice as high when judged by depression symptomatology rather than clinical diagnosis. The critical risk factors were functional impairments, poor cognitive abilities and the presence of chronic physical illnesses.
