Cross-sectional studies have found that depression is uniquely associated with limitations in wellbeing and functioning that were equal to or greater than those of chronic general medical conditions such as diabetes and arthritis. However, whether these relative limitations persist over time is not known.
We conducted a 2-year observational study of 1790 adult outpatients with depression, diabetes, hypertension, recent myocardial infarction, and/or congestive heart failure. Change in functional status and wellbeing was compared for depressed patients vs patients with chronic general medical illnesses, controlling statistically for medical comorbidity, sociodemographics, system, and specialty of care.
Over 2 years of follow-up, limitations in functioning and well-being improved somewhat for depressed patients; even so, at the end of 2 years, these limitations were similar to or worse than those attributed to chronic medical illnesses. Similar patterns were observed for depressed patients in the mental health specialty sector and those in the general medical sector, but the patients in the mental health specialty sector improved more. More severely depressed patients improved more in functioning, but even initially depressed patients without depressive disorder had substantial persistent limitations.
Depressed patients have substantial and long-lasting decrements in multiple domains of functioning and well-being that equal or exceed those of patients with chronic medical illnesses.