Depression and the nature of Trinidadian family practice: a cross-sectional study

Depression is the most common mental disorder; in an ambulatory-care setting 5 to 10% of patients meet the criteria for major depression. Despite extensive documentation in primary care internationally, Trinidadian studies published on depression have been primarily hospital-based and focussed on suicide. The objectives of this study were to determine the prevalence of depression, the variables associated with depression and the commonest reason for the encounter (RFE) among adult patients attending Trinidadian fee-for-service family practice?

This was a cross-sectional descriptive survey of consecutive patients taken from a stratified random sample of family practices in the north-west region of Trinidad. To measure depression the Zung scale was modified for use as a brief diagnostic tool. This modified Zung scale, when tested against a psychiatric interview, revealed that at a cut off point of 60, the scale had a specificity of 94% (95% CI 87–100), a sensitivity of 60% (95% CI 45–75), and a likelihood ratio for a positive test result of 10 (95% CI 6–42).

508 patients from 28 practices participated; a response rate of 85%. Participants were primarily younger 18–49 years (66.7%), female (69.5%), and educated, with 72.8% having received a secondary school, technical school or university education. Sixty-five (12.8%) of the respondents (95% CI 9.9–15.7) were determined to be depressed. Chi-square analysis revealed no statistically significant association between depression and age, ethnicity, education levels, occupation or marital status (p > 0.05). Binary logistic regression indicated that the likelihood of being depressed (p < 0.05) decreased with the increasing age of the patient and was inversely proportional to patient's achieved level of education; and that patients not presently in a relationship were more likely to be depressed than patients who were currently in a relationship. The 508 participants had 630 RFE, with 'check-ups' (17.5%) being the commonest, followed by joint pains (13.4%) and upper respiratory infections (10.5%).

The Trinidadian family physician has to maintain a high index of suspicion in the knowledge that as many as one of every eight adult patients may be depressed and that younger patients of lower educational status who were not currently in a relationship were more likely to be depressed.