Combined effect of cognitive impairment and depressive symptoms on the fall risk of the elderly in Taiwan

Background:Although both cognitive impairment and depressive symptoms are risk predictors of falls in the elderly, their combined effect on fall risk remains unknown.

Methods:Data of the 2003 and 2007 Taiwan Longitudinal Study on Ageing (TLSA) were used to study the association between a variety of combination of cognitive impairment and depressive symptoms (depressive symptoms only, cognitive impairment only, and both) in 2003 with fall experience in 2007. Cognitive impairment and depressive symptoms were respectively measured with the Short Portable Mental Status Questionnaire and the Centers for Epidemiologic Studies Depression Scale. Other explanatory variables measured in the 2003 TLSA included age, gender, IADL dependence, taking sleeping pills or sedative, vision, walk aid use, frequency of exercise, total number of chronic conditions. The association was firstly examined in single-variate and bi-variate analyses, and further investigated in multivariate logistic regression models.

Results:2,700 adults aged 65 or over with a mean age of 76.2 ±7.2 years were followed up from 2003 to 2007. The prevalence of falls increased from 20.56% for those older adults with neither cognitive impairment nor depressive symptoms to 27.43%, 38.12%, and 27.23% respectively for those having depressive symptoms only, cognitive impairment only, and both, with corresponding adjusted PORs: 1.33 (95% CI 1.03-1.72), 1.62 (95% CI 1.05-2.51), and 0.91 (95% CI 0.86-2.14) when controlled for other explanatory variables mentioned above.

Conclusions�:The combined effect of cognitive impairment and depressive symptoms on the fall risk of the elderly was not so significant as that of either one.