Iyengar yoga and health education interventions for prolonged grief disorder in later life: feasibility of a randomized controlled pilot trial

Mind body therapies, particularly yoga, may offer a simple, scalable, and effective intervention for prolonged grief disorder (PGD) in older adults. This pilot randomized controlled trial (RCT) compared Iyengar Yoga (IY) with Health Education (HE), an active control, assessing feasibility, safety, and clinical effects in those with probable PGD in later life. Thirty-nine bereaved adults (median age: 62.0 years) with probable PGD were randomized to IY (n = 19) or HE (n = 20). Participants attended 60-min weekly group sessions for 10 weeks. Feasibility, safety, IY instructor fidelity, and grief and depressive symptoms were assessed over time, with effect sizes (Hedges' g) calculated to explore within-group and between-group clinical changes. Retention was 84.6%, with 100% of participants attending at least one session. Among completers (n = 33), 90.9% attended at least 80% of sessions. IY completers submitted an average of 8.65 weekly homework logs, and 82% practiced yoga at home for 60 + minutes weekly. All randomly selected IY classes met instructor fidelity. Participants in both groups reported high satisfaction; IY participants endorsed greater perceived benefits. No serious adverse events occurred. Both groups showed clinical improvements, with mean effect sizes ranging from 0.69 to 1.28 (medium to large) for overall grief and depressive symptoms, and 0.28 to 0.88 (small to large) for grief-specific symptoms. Between-group effect sizes for clinical outcomes were small. An IY and HE group intervention trial is feasible, safe, and acceptable for adults with PGD in later life. A larger, adequately powered RCT is needed to establish clinical efficacy of these interventions for late-life PGD.Trial registration. The trial is registered at ClinicalTrials.gov (NCT05026827, 08/30/2021).