Background: Anxiety is a complicating comorbid diagnosis in many patients with medical illnesses. In patients with end-stage renal disease (ESRD), anxiety disorders often are perceived to represent symptoms of depression rather than independent conditions and therefore have been relatively understudied in this medical population.
Study design: To evaluate the psychosocial impact of anxiety disorders on patients with ESRD, we sought to identify the rates of these disorders in a sample of patients receiving hemodialysis at a single center by using a structured clinical interview. We also compared a commonly used screening measure, the Hospital Anxiety and Depression Scale (HADS), with these clinical diagnoses to determine the measure's criterion validity or ability to predict a psychiatric diagnosis in ESRD populations. Finally, we examined the relationship between anxiety diagnosis and perceptions of quality of life (QOL) and health status.
Setting & participants: A sample of 70 randomly selected hemodialysis patients from an urban metropolitan center.
Predictor: Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) Axis I Diagnosis (SCID-I).
Outcomes: HADS and Kidney Disease Quality of Life Short Form.
Results: Using the SCID, 71% of the sample received a DSM-IV Axis I diagnosis, with 45.7% of subjects meeting criteria for an anxiety disorder and 40% meeting criteria for a mood disorder. The concordance between DSM-IV anxiety disorders and anxiety scores acquired by using the HADS was not significant. Thus, although the HADS may provide an acceptable measure of overall "psychic distress" compared against the SCID-I, it has poor predictive power for anxiety diagnoses in patients with ESRD. Additionally, the presence of an anxiety disorder was associated with an overall perceived lower QOL (t = 2.4; P < 0.05).
Limitations: Single-center study and a population not representative of US demographics.
Conclusions: A substantial proportion of participating patients met criteria for an anxiety disorder. The utility of the HADS as a screening tool for anxiety in patients with ESRD should be questioned. The finding that anxiety disorders negatively impact on QOL and are not merely manifestations of depression in patients with ESRD emphasizes the importance of accurate diagnosis and effective treatment. Strategic options are necessary to improve the diagnosis of anxiety disorders, potentially enhancing QOL and medical outcome in patients with ESRD.