Longitudinal investigation of depression outcomes in primary care in six countries: the LIDO Study. Functional status, health service use and treatment of people with depressive symptoms

Background. Screening surveys of depressive symptoms were conducted among primary care patients at six sites in different countries. The LIDO Study was designed to assess quality of life and economic correlates of depression and its treatment in culturally diverse primary health care settings. This paper describes: (1) the association between depressive symptoms and functional status, global health-related quality of life (QoL), and use of general health services across different cultural settings; and (2) among subjects with depressive symptoms, the factors associated with recent treatment for depression. Methods. Subjects aged 18 to 75 were recruited from participating primary care facilities in Be'er Sheva (Israel), Porto Alegre (Brazil), Melbourne (Australia), Barcelona (Spain), St Petersburg (Russian Federation) and Seattle (USA). Depressive symptoms were measured using the CES-D. Also administered were the SF-12, global questions on QoL, selected demographic and social measures, and questions on recent treatment for depression, use of health care services, and lost workdays. Results. A total of 18 489 patients were screened, of whom 37% overall (range 24-55%) scored greater than or equal to16 on the CES-D and 28% (range 17-42%) scored greater than or equal to 20. Overall, 13% reported current treatment for depression (range 4 to 23%). Patients with higher depressive symptom scores had worse health, functional status, QoL, and greater use of health services across all sites. Among those with a CES-D score greater than or equal to 16, subjects reporting treatment for depression were more likely than those reporting no treatment to be dissatisfied with their health (except in St Petersburg), and to have higher depressive symptom scores. Conclusions. Higher depressive symptom scores in primary care patients were consistently associated with poorer health, functional status and QoL, and increased health care use, but not with demographic variables. The likelihood of treatment for depression was associated with perceptions of health, as well as severity of the depression.