Prevention of late-life anxiety and depression has sustained effects over 24 months: a pragmatic randomized trial.

Objective: Depressive and anxiety disorders in later life have a high incidence and are associated with reduced quality of life. Elsewhere, we demonstrated that a stepped-care prevention approach was successful in halving the incidence of these disorders over a period of 12 months. As a decreasing effect over time is to be expected, our aim was to investigate the longer-term effects.

Design: Randomized controlled trial.

Setting: Thirty-three primary care practices in the Netherlands.

Participants: One hundred seventy consenting individuals, age 75 years and older, presenting with subthreshold depression or anxiety, not meeting the diagnostic criteria.

Intervention: Participants were randomized to a preventive intervention or usual care. In the first 12 months, the preventive intervention entailed watchful waiting, minimally supported CBT-based self-help intervention, problem-solving treatment, and referral to a primary care physician for medication, if required. In the last 12 months, 95% of the participants ceased to receive such support.

Measurements: Mini International Neuropsychiatric Interview.

Results: The cumulative incidence rate of Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, major depression or anxiety disorder over a period of 24 months was halved by the intervention, from 33 of 84 (39.3%) in the usual care group to 17 of 86 (19.8%) in the intervention group (odds ratio = 0.38; 95% confidence interval = 0.19–0.76), which was significant (z = 2.75; p = 0.006). The corresponding number needed to treat was 5 (95% confidence interval = 3–16).

Conclusions: A stepped-care approach to the prevention of depression and anxiety in late life was not only successful in halving the incidence of depressive and anxiety disorders after 1 year, but these favorable effects were also sustained over 24 months.