Aerobic, resistance, and mind-body exercise are equivalent to mitigate symptoms of depression in older adults: A systematic review and network meta-analysis of randomised controlled trials [version 2; peer review: 2 approved, 1 approved with reservations]

Background: Exercise has been identified as an allied health strategy that can support the management of depression in older adults, yet the relative effectiveness for different exercise modalities is unknown. To meet this gap in knowledge, we present a systematic review and network meta-analysis of randomised controlled trials (RCTs) to examine the head-to-head effectiveness of aerobic, resistance, and mind-body exercise to mitigate depressive symptoms in adults aged ≥ 65 years. Methods: A PRISMA-NMA compliant review was undertaken on RCTs from inception to September 12th, 2019. PubMed, Web of Science, CINAHL, Health Source: Nursing/Academic Edition, PsycARTICLES, PsycINFO, and SPORTDiscus were systematically searched for eligible RCTs enrolling adults with a mean age ≥ 65 years, comparing one or more exercise intervention arms, and which used valid measures of depressive symptomology. Comparative effectiveness was evaluated using network meta-analysis to combine direct and indirect evidence, controlling for inherent variation in trial control groups. Results: The systematic review included 82 RCTs, with 69 meeting eligibility for the network meta-analysis (n = 5,379 participants). Pooled analysis found each exercise type to be effective compared with controls (Hedges’ g = -0.27 to -0.51). Relative head-to-head comparisons were statistically comparable between exercise types: resistance versus aerobic (Hedges’ g = -0.06, PrI = -0.91, 0.79), mind-body versus aerobic (Hedges’ g = -0.12, PrI = -0.95, 0.72), mind-body versus resistance (Hedges’ g = -0.06, PrI = -0.90, 0.79). High levels of compliance were demonstrated for each exercise treatment. Conclusions: Aerobic, resistance, and mind-body exercise demonstrate equivalence to mitigate symptoms of depression in older adults aged ≥ 65 years, with comparably encouraging levels of compliance to exercise treatment. These findings coalesce with previous findings in clinically depressed older adults to encourage personal preference when prescribing exercise for depressive symptoms in older adults. Registration: PROSPERO CRD42018115866 (23/11/2018)