Physical activity and neurotrophic factors as potential drivers of neuroplasticity in Parkinson's Disease: A systematic review and meta-analysis.
Level 1 - systematic review of randomized trials
Systematic review and meta-analysis of randomized controlled trials
PubMed 37844764 · doi:10.1016/j.arr.2023.102089
What was done
A systematic review and random-effects meta-analysis evaluated 20 years of randomized and non-randomized controlled trials investigating the effect of exercise interventions on serum and plasma neurotrophic factors in patients with Parkinson's disease. Exercise programs across 18 included studies were standardized by type, intensity, and duration. Six randomized controlled trials reporting BDNF and IGF-1 outcomes were included in quantitative meta-analyses.
What was found
Physical activity resulted in a statistically significant increase in serum BDNF concentration compared with control conditions in RCTs (mean difference: 5.99 ng/mL; 95% CI: 0.15 to 11.83; I² = 77%). Serum IGF-1 also increased in exercising patients compared with controls (mean difference: 33.47 ng/mL; 95% CI: 8.09 to 58.85). Preliminary evidence suggesting moderate-intensity aerobic exercise was required to induce neurotrophic changes was not confirmed in sensitivity or subgroup analyses.
Why it matters
This review provides quantitative clinical trial evidence that exercise elevates circulating BDNF and IGF-1 in Parkinson's disease, supporting neurotrophic upregulation as a biological mechanism for exercise-induced neuroplasticity.
Limits
Only 6 of 18 identified studies were suitable for meta-analysis, and total participant numbers were not stated in the abstract. Statistical heterogeneity for BDNF was substantial (I² = 77%), and subgroup findings lacked stability across sensitivity analyses.
Cited by
- supports In Parkinson's disease patients, 30 minutes of moderate-to-high intensity exercise increases plasma BDNF, and BDNF crosses the blood-brain barrier.