Sensitivity and specificity of the Geriatric Anxiety Inventory and the Hospital Anxiety and Depression Scale in the detection of anxiety disorders in older people with chronic obstructive pulmonary disease

Background: Anxiety and depression are prevalent in patients with chronic obstructive pulmonary disease (COPD). This study evaluates the sensitivity and specificity of two self-administered anxiety rating scales in older people with COPD. The Geriatric Anxiety Inventory (GAI) and the Hospital Anxiety and Depression Scale (HADS) are established useful screening tools but they have not been previously validated in this population. Methods: Older people with COPD completed the GAI and the HADS along with a structured diagnostic psychiatric interview, the Mini International Neuropsychiatric Interview (MINI). The outcomes of both rating scales were compared against the diagnosis of anxiety disorders based on the MINI. Receiver operating characteristic (ROC) curves were used to identify the optimal diagnostic cut points for each scale. Results: Fourteen (25.5%) of the 55 participants, were diagnosed with an anxiety disorder. Mean GAI and HADS-anxiety subscale scores were significantly higher in subjects with an anxiety disorder than those without the diagnosis (p = 0.002 and 0.005 respectively). Both scales demonstrated moderate diagnostic value (area under the ROC curve was 0.83 for GAI and 0.79 for HADS). Optimal cut points were >= 3 (GAI) and >= 4 (HADS-anxiety subscale). At these cut-points, the GAI had a sensitivity of 85.7%, specificity of 78.0% and the HADS had a sensitivity of 78.6%, specificity 70.7%. Conclusion: Our results support the use of the GAI and HADS as screening instruments for anxiety disorders in older people with COPD. The optimal cut points in this population were lower than previously recommended for both rating scales. The results of this study should be replicated before these cut points can be recommended for general use in older people with COPD.