The high incidence of depression in end-stage renal disease (ESRD) patients is well documented. Our group and others have estimated that 20-30% of ESRD patients experience major depression. Several recent studies have emphasized the relationship between depressive symptoms and mortality and morbidity in both hemodialysis (HD) and peritoneal dialysis (PD) patients. We screened 380 PD patients for depression using the Beck Depression Inventory (BDI). The mean patient age was 59.9 +/- 14.1 (SD) years, 55% were Caucasian, 51% were male, and 39% had diabetes. The mean BDI score was 12.1 +/- 7.7; 49% had a score of 11 or greater. Fifty-five percent refused further assessment to confirm the diagnosis of major depression, while 45% of patients eligible for treatment agreed to further assessment. Their mean BDI was 18.8 +/- 6.2. Eighty-four percent were diagnosed with major depression on direct interviews and offered pharmacologic treatment, 16% did not meet the criteria for a diagnosis of depression, and 50% successfully completed 12 weeks of pharmacologic treatment. The BDI score of these patients at the start of treatment was 17.4 +/- 6.6, and at completion of treatment it was 8.4 +/- 3.0. Thirty-eight percent of treatment failures were in those who were also diagnosed with a DSM-IV personality disorder. Major depression is common in PD patients, and is potentially treatable with pharmacologic therapy. However, there are major problems providing a depression assessment and treatment program to such patients. Problems include refusal to complete depression assessment and patients with axis 2 personality disorders who have difficulty complying with treatment. Although depression treatment can improve depressive symptoms, it is unclear whether such therapy will improve medical outcomes.