Optimizing Detection of Major Depression Among Patients with Coronary Artery Disease Using the Patient Health Questionnaire: Data from the Heart and Soul Study

Abstract

BACKGROUND

Clinical guidelines recommend depression screening in patients with coronary artery disease (CAD), but how to accomplish this is unclear.

OBJECTIVE

We evaluated the test characteristics of the two-item Patient Health Questionnaire (PHQ-2), the nine-item Patient Health Questionnaire (PHQ-9), and a two-step screening approach (PHQ-2 then PHQ-9 if positive on PHQ-2), compared with the Computerized Diagnostic Interview Schedule (C-DIS) for major depression. We also evaluated a “PHQ diagnosis” of depression, requiring five of nine symptoms “more than half the days,” compared with the C-DIS.

DESIGN

Cross-sectional study of 1,024 outpatients with CAD.

MAIN RESULTS

Two hundred twenty-four patients (22%) had current major depression. Optimal cutpoints were ≥2 for the PHQ-2 (82% sensitive, 79% specific) and ≥6 for the PHQ-9 (83% sensitive, 76% specific). The two-step screening approach was less sensitive (75%), but more specific (84%), than the PHQ-2 or PHQ-9 alone. The “PHQ diagnosis” had low sensitivity (28%), but high specificity (96%).

CONCLUSIONS

Cutpoints of ≥2 on the PHQ-2 and ≥6 on the PHQ-9 had similar test characteristics. A two-step approach using the PHQ-2 followed by the PHQ-9 was no better than either instrument alone. A “PHQ diagnosis” of depression had high specificity, but poor sensitivity.