Measurement of depression in patients with chronic obstructive pulmonary disease (COPD)

Objective: To estimate the validity of the Hamilton Depression Scale (HDS) in a population of patients with chronic obstructive pulmonary disease (COPD). Methods: Forty-nine patients with moderate to severe COPD were examined using the ICD-10 criteria for depression. The mean age of the patients was 71 years and 33 (64%) were women. Forty-six (94%) of the patients were also evaluated using the 17-item HDS including the six-item Hamilton Depression subscale (HDSS). Internal and external validity were measured using factor analysis, Cronbach Coefficient alpha, Loevinger coefficient of homogeneity, correlation analysis and ROC-curves. Results: Twenty-three (47%) of the patients were depressed according to the ICD-10 criteria for depression. The HDSS but not the HDS showed a good internal validity. An acceptable external validity was furthermore shown for the HDSS. Conclusion: The HDSS can be recommended as a suitable depression rating scale for COPD patients.