Use of PHQ-9 for monitoring patients with depression in integrated primary care practices

Context: The PHQ-9 is a validated, short self-report questionnaire designed to be used in primary care for diagnosis and management of depression. We wished to assess its use for monitoring symptoms in patients being treated for depression.

Objective: to measure the use of the PHQ-9 in 12 months following an elevated score in adult patients in primary care practices.

Study design: retrospective cohort study with descriptive analysis of use of PHQ-9 for follow up; stratified by age category, gender, severity and chronicity of symptoms, and whether referred to integrated behavioral health.

Setting or Dataset: EMR data including dates and results of PHQ-9, patient demographics, and referral data.

Population Studied: Adults aged 18 and older with a PHQ-9 score of 10 or higher during calendar year 2018. No one was excluded.

Outcome measure: Primary outcome measure was the number of PHQ-9’s done in 12 months following the initial elevated score (index score). Secondary outcome measures are a set of quality measures for depression care related to monitoring with PHQ-9 at 6 and 12 months following index score.

Results: among all patients, mean number of PHQ-9 following index score was 2.1. This was increased for those with chronic symptoms (defined as having an elevated score at least once in calendar year 2017. It was increased slightly as severity of index symptoms increased. It was increased substantially for those referred to integrated behavioral health clinicians in the practices.

Conclusions: the PHQ-9 is underutilized as an instrument for monitoring patients who are being treated for depression in primary care. Measurement based care has a strong evidence base and interventions to improve utilization of the PHQ-9 for monitoring are likely to improve depression outcomes in primary care.