Screening for depression in acute coronary syndrome patients: A comparison of Patient Health Questionnaire-9 versus Hospital Anxiety and Depression Scale-Depression

Objective: To assess the reliability and criterion validity of Patient Health Questionnaire-9 (PHQ-9) versus Hospital Anxiety and Depression Scale-Depression (HADS-D) as screening instruments for depression in patients with the acute coronary syndrome (ACS). Methods: A total of 782 patients were recruited from four local hospitals. All of them completed the questionnaires of PHQ-9 and HADS-D. The measures of PHQ-9 and HADS-D were validated against the Mini International Neuropsychiatric Interview (MINI), a gold diagnostic criterion for major depressive disorder (MDD). Results: Based upon the MINI, the prevalence of MDD was 15.6% in Chinese ACS patients. Two scales demonstrated excellent internal consistencies (Cronbach's alpha > 0.8). The diagnostic accuracy of PHQ-9 and HADS-D for diagnosing MDD was moderate with areas under receiver operating characteristics (ROC) curve of 0.842 (95%CI: 0.806-0.894) and 0.813 (95%CI: 0.767-0.852), respectively. The optimal cutoff points of PHQ-9 and HADS-D for screening MDD were 10 and 9, respectively. Comparing the operating characteristics of PHQ-9 and HADS-D, the specificity was similar (84.7% vs. 85.5%, p =.40) while the sensitivity of PHQ-9 was significantly higher than HADS-D (86.9% vs. 76.2%, p =.001). Conclusion: Chinese versions of PHQ-9 and HADS-D are reliable and valid screening instruments for MDD in ACS patients. The PHQ-9 performs better in minimizing missed diagnoses.