One in five patients with chronic kidney disease is depressed, even before beginning long-term dialysis therapy or developing end-stage renal disease, UT Southwestern Medical Center researchers have found.
The study, based on a pool of 272 participants, is the first to examine the rate of depression among these patients using the Diagnostic and Statistical Manual of Mental Disorders 4th edition (DSM IV), which is considered the gold-standard in evaluating depression.
"Because patients in the early stages of chronic kidney disease are at increased risk for clinical depression, we as nephrologists should consider screening our patients for depression in clinic," said Dr. Susan Hedayati, assistant professor of internal medicine at UT Southwestern and a staff nephrologist at the Dallas Veterans Affairs Medical Center. She is the lead author of the study, available online and in the current issue of the American Journal of Kidney Diseases.
Previous research has shown that depression rates in the general community are 2 percent to 4 percent; among diabetes patients, 11 percent; among congestive heart failure patients, 14 percent; and among coronary artery disease after heart attack patients, 16 percent.
"Chronic kidney disease patient depression numbers may be higher due to the presence of the same simultaneously occurring conditions that resulted in progressive kidney disease, such as diabetes and atherosclerotic vascular disease," Dr. Hedayati said. "Alternatively, patients such as diabetics, who are depressed, may develop progressive kidney disease because of non-adherence to medications and physicians' advice."
Earlier estimates of depression among chronic kidney disease patients were based on self-report depression scales that can emphasize symptoms such as lack of appetite, weight loss and fatigue. Such symptoms can overlap with other medical conditions, so UT Southwestern researchers took a novel approach.
From May 2005 to November 2006, researchers invited patients at the Dallas VA Medical Center who were visiting the clinic for chronic kidney disease appointments to join the study. Patients who agreed to participate then underwent a structured clinical interview to determine if they had a current major depressive episode, based on the DSM IV definition of major depressive disorder.