Assessing depression and anxiety in chronic dialysis patients.

One hundred and twenty-eight patients on chronic dialysis were studied by the Zung Self-Rating Depression Scale and Self-Rating Anxiety Scale, the Differential Emotion Scale (DES), the Test of Emotional Styles (TES), and the Social Dysfunction Rating Scale (SDRS). As measured by the Zung scales, approximately half of the sample manifested depression and anxiety symptoms at clinically relevant levels. The data suggested an inverse correlation between depression and anxiety levels and patients' total length of time on dialysis, which may explain some of the variation in depression and anxiety results obtained with different samples. Depression and anxiety scores were correlated with related DES and SDRS factors, but patients' scores on the DES, TES, and SDRS generally indicated positive mood and functioning. Scales containing disease-related somatic items may yield exaggerated depression and anxiety scores for dialysis patients. It may be useful to assess patients' psychological functioning with several different instruments.