Prevalence and determinants of depressive disorders in primary care practice in Spain.

OBJECTIVE: Depressive disorders are considered to be a public health problem. Primary health care plays an important role in the treatment of such disorders. Our aim is to determine the prevalence and determinant factors of major depression and dysthymia in consecutive primary care attenders.
METHOD: The study took place in medical consultations in 10 Primary Care Centers in Tarragona (Spain). It was designed as a two-phase cross-sectional study. In the first phase we screened 906 consecutive patients according to Zung's Self-Rating Depression Scale. In the second phase the 209 patients whose results were positive and 97 patients whose results were negative (1/7 chosen at random) were given the Structured Clinical Interview for DSM-IV Axis I Disorders, plus a series of questionnaires. We evaluated the link between major depression and dysthymia and several sociodemographic and clinical variables using non-conditional logistic regression.
RESULTS: Weighted prevalence was 14.3% (CI 95%: 11.2-17.4) for major depression and 4.8% (CI 95%: 2.8-6.8) for dysthymia. Independently linked to the presence of major depression were female sex, panic disorder, generalized anxiety disorder, frequency of primary care visits, and clinical presentation in the form of explicitly psychosocial symptoms as opposed to exclusively somatic symptoms. Independently linked to the presence of dysthymia were age, generalized anxiety disorder and psychosocial symptoms.
CONCLUSION: In our area, depressive disorders in primary care attenders are very common. General practitioners should be aware of this fact so that these disorders can be detected and treated correctly.