Obesity and depressive symptoms in Chinese elderly

The main objective was to examine the association between obesity and depressive symptoms among Chinese elderly in Hong Kong.

Cross-sectional data on depressive symptoms and body mass index from 56 167 clients aged 65 or over who enrolled as members of Elderly Health Centres from July 1998 to December 2000 were analysed using multiple logistic regression with adjustment of potential confounders.

Among 18 750 men and 37 417 women, the prevalence [95% confidence interval (CI)] of depressive symptoms (based on the Geriatric Depression Scale) was 4.9% (4.6-5.2%) and 7.9% (7.6-8.1%) respectively (p < 0.001). The prevalence of obesity (by World Health Organisation Asian standard: body mass index > or =25.0) in women was significantly higher than that of men (42.1% (41.6-42.7%) vs 36.6% (35.9-37.3%), p < 0.001). Obese men and women were about 20% less likely to suffer from depressive symptoms compared with those with normal weight after adjustment for confounders, with odds ratios (95% CI) of 0.82 (0.69-0.97) and 0.78 (0.71-0.86) respectively. Negative linear trends were observed between depressive symptoms and BMI categories in both sexes, and women showed a greater slope and stronger statistical significance than men.

Both obese elderly men and women in Hong Kong were less likely to suffer from depressive symptoms than those of normal weight. The results support the 'jolly fat' hypothesis previously restricted to men, and extend the hypothesis to female elderly. Chinese traditional culture and positive values towards obesity may be protective against depressive symptoms.