PURPOSE Our objective was to examine the relative association of depression severity and chronicity, other comorbid psychiatric conditions, and coexisting medical illnesses with multiple domains of health status among primary care patients with clinical depression.
METHODSWe collected cross-sectional data as part of a treatment effectiveness trial that was conducted in 8 diverse health care organizations. Patients aged 60 years and older (N = 1,801) who met diagnostic criteria for major depression or dysthymia participated in a baseline survey. A survey instrument included questions on sociodemographic characteristics, depression severity and chronicity, neuroticism, and the presence of 11 common chronic medical illnesses, as well as questions screening for panic disorder and posttraumatic stress disorder. Measures of 4 general health indicators (physical and mental component scales of the SF-12, Sheehan Disability Index, and global quality of life) were included. We conducted separate mixed-effect regression linear models predicting each of the 4 general health indicators.RESULTS Depression severity was signifi cantly associated with all 4 indicators of general health after controlling for sociodemographic differences, other psychological dysfunction, and the presence of 11 chronic medical conditions. Although study participants had an average of 3.8 chronic medical illnesses, depression severity made larger independent contributions to 3 of the 4 general health indicators (mental functional status, disability, and quality of life) than the medical comorbidities.CONCLUSIONS Recognition and treatment of depression has the potential to improve functioning and quality of life in spite of the presence of other medical comorbidities. 2004;2:555-562. DOI: 10.1370/afm.143.
Ann Fam Med
INTRODUCTIONE pidemiological and clinical studies consistently indicate that depression adversely affects the lives of older adults. The relative contribution to adverse effects is not entirely clear, because depression often occurs in conjunction with other psychiatric illnesses, such as anxiety disorders; somatic symptoms, such as pain; and chronic medical illnesses, such as diabetes. The latter is particularly of concern, because it is often diffi cult to know whether a particular symptom, such as lethargy, is caused by depression, a coexisting medical illness, or both. Patients with chronic medical illness are known to have a high prevalence of comorbid depression.1 Furthermore, both major depressive disorder and subsyndromal depression have been associated with increased somatic symptoms, morbidity, mortality, health care utilization, and costs in the presence of comorbidities. 5-7 Furthermore, severity of depressive symptoms is inversely related to patients' health-related quality of life, even after controlling for age, sex, and medical comorbidities. 8,9 Many older persons, however, have more than one chronic illness that may differentially impair health status. Elders with multiple comorbidities may be particularly vulne...