Background: The difficulty in identifying and distinguishing Major Depressive Disorder (MDD) in primary care is well known. The main objective of this study is to determine the frequency of MDD in persons aged 65 years and older using the Detection of Depression in the Elderly Scale (DDES). A second objective is to determine the convergent validity of the DDES with the Geriatric Depression Scale (GDS).
Methods: A cross-sectional, observational study was carried out of 1,387 subjects aged 65 years and older. The variables considered were: affective state (GDS and DDES), physical and cognitive functional state, health problems and sociodemographic characteristics.
Results: Using the DDES we identified MDD in 50 subjects (4.3%). There was a moderate correlation (r = 0.570; p < 0.001) between the DDES and the GDS scores (p < 0.001). According to logistic regression analysis, the variables associated with a probable MDD (DDES +) were: dependence in activities of daily living (OR: 3.3), female gender (OR: 2.3), marital status single/widowed/divorced (OR: 2.0), and the presence of four of more health problems (OR: 2.1).
Conclusions: Using the DDES scale we found a 4.3% prevalence of MDD in a representative sample of older adults. Compared to the GDS, the most commonly used scale, the DDES may be considered a more sensitive screening tool for the identification of MDD in primary care.