Objectives: To determine the prevalence of the risk of depression, major defining characteristics and factors associated with. Design: Sub-study of comprehensive geriatric assessment cross-study. Setting: Primary health center. Participants: For an estimated 14% prevalence we need a sample of 288 people. From 3854, 290 people >= 75 years were selected. Excluding terminals, chemotherapy, recent surgery, temporary residence, mental retardation, serious psychiatric illness, or under home care. Measurement: Outcome: risk of depression (>= 2 points on the Goldberg depression subscale. Dependent variables: Sociodemographic and five study areas of the Comprehensive Geriatric Assessment: medical -comorbidity, polypharmacy, falls and hospital admissions-, functional -Up&Go Test, Lawton-Brody and Barthel Index-, nutritional -Mini Nutritional Assessment (MNA)-, mental-affective -Pfeiffer Questionnaire and Goldberg scale-, and social. Descriptive analysis and logistic regression. Results: We obtained 290 interviews, with 102 (35.1%) male and mean age of 79.4 years (SD: 3.2). The prevalence of the risk of depression was 37.2%, 26.5% in men and 43.1% in women (p = 0.005). Association of risk of depression is observed with arterial hypertension (OR: 3.87 95% CI: 1.61-9.34), cancer (OR : 4.12 95%, CI : 1.58-10.76), lack of leisure activity (OR : 2.75 95%, CI : 1.33-5.67), increase of anxiety scale (OR : 1.87 95%, CI: 1.57-2.22) and decrease in MNA (OR: 0.78 95%, CI: 0.68-0.9). Conclusions: The prevalence of risk of depression is higher than expected, although overestimated until being confirmed with a diagnostic test. We appreciate new associations of comorbidity variables with risk of depression and corroborate other known. The studied factors that were associated with the risk of depression should be included in future studies of geriatric depression. (C) 2014 Elsevier Espana, S.L.U. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).