Prevalence of depression among older adults with dementia living in low- and middle-income countries: a cross-sectional study

Background: The prevalence of depression has been evaluated in populations of low- and middle-income (LMI) countries but the risk of depression has not been specified among persons with dementia. This cross-sectional analysis aimed to assess the prevalence and risk of depression among older people with dementia living in LMI countries. Methods: The study analysed data from a population-based survey conducted by 10/66 Dementia Research Group in 2004. Altogether, 17 031 participants from eight different countries aged 65 years and above were assessed. Logistic regression was used to calculate prevalence and odds ratio (OR) of depression on persons with dementia. Adjustments by age and education were included in the analysis. ORs of depression on different types of dementia were determined. Results: Depression was identified in 5.8% (4.4% of men, 6.6% of women) of all the 17 031 participants and in 12.4% (18.9% of men, 10.1% of women) of the 1612 persons with dementia. Persons with dementia had an increased risk of depression compared with persons without dementia, the age- and education-adjusted OR was 2.38 [95% confidence interval (CI0 1.99-2.84]); 3.86 (95% CI 2.83-5.26) for men and 1.88 (95% CI 1.51-2.35) for women. Compared with Alzheimer's disease, Lewy body [OR 2.75 (95% CI 1.40-3.72)] and vascular dementia [OR 2.35, (95% CI 1.49-3.72)] were associated with a higher risk of depression. Conclusions: Persons with dementia were twice as likely to have depression as persons without dementia. Among persons with dementia, the prevalence of depression was higher for men than women, and the risk of depression varied by the type of dementia.