PHQ-9 Depression Screening

The Importance of PHQ-9 Screening at the Primary Care Level

Depression and suicide are two major health risks, both in the U.S. and abroad. 20–25% of adult Americans struggle with depression, while 38,000 Americans commit suicide each year. The CDC identifies suicide as the third most prevalent cause of death for youth between 10 and 24 years old. According to the World Health Organization, the past 50 years have seen a 60% increase in suicide rates, and by 2020 depression was projected to become the second most widespread medical condition globally.

Approximately two-thirds of American patients with depression see a primary care physician for treatment. 40% of suicide victims see a primary care physician one month prior to committing suicide. Yet primary care physicians fail to screen and diagnose as many as 30–50% of depressed patients.

The Two-Step Screening Strategy

Depression screening at the primary care level involves a two-step strategy:

• Step 1: Ask two screening questions: (1) During the past month, have you often been bothered by feeling down, depressed, or hopeless? (2) During the past month, have you often been bothered by little interest or pleasure in doing things?
• Step 2: If the patient says yes to either question, guide them through the full PHQ-9 questionnaire (9 questions).

PHQ-9 vs PHQ-9A

The Adult and Adolescent Depression Screening, Diagnosis, and Treatment Guide distinguishes between two age-appropriate versions:

• PHQ-9 — for adults 18 years of age and older
• PHQ-9A — for adolescent patients ages 12–17

Key 2015 Updates to PHQ-9 Screening

• Use of the Columbia Suicide Risk Assessment tool for high-risk patients
• Enhanced shared decision making between physicians and patients
• Antidepressant use prioritized only for patients with severe depression

Treatment Goals

The primary care physician's primary goal is to effectively diagnose and treat depression symptoms in individual patients. The two main treatment goals are:

• Attain complete remission of depression
• Prevent a future relapse of the depression

Combination treatment (medication + supportive care) is particularly effective compared to either method alone. Supportive care includes educating the patient about the biological and circumstantial causes of depression, follow-up visits, and shared decision making.

Treatment Duration

Patients who have had only one episode of major depression should continue antidepressants 6–12 months after remission. Patients with two or more episodes should have a longer treatment period of 3 or more years. Physicians should wean patients off antidepressants gradually to minimize relapse risk.