Among primary care patients with subthreshold depression, mindfulness meditation training reduces the incidence of major depression and improves depression symptoms. A randomized controlled trial of adults with subthreshold depression compared a usual care group in which there was no psychological intervention (n=116) with a behavioral activation group focused on mindfulness training (n=115).
Intervention participants were invited to attend weekly two-hour mindfulness training sessions for eight consecutive weeks. At 12 months, there was a statistically significant difference in the incidence of major depressive disorder between groups (11 percent in the mindfulness group compared to 27 percent in usual care). Mindfulness training also had a small effect in reducing depression symptoms (between-group mean difference = 3.85). Other secondary outcomes demonstrated no significant change. The authors suggest that, for patients with subthreshold depression who have not had a major depressive episode in the past six months, mindfulness training is a feasible method of preventing major depression. The authors plan future research into the cost-effectiveness, health service use implications, and acceptability of mindfulness training.