Association between diabetes mellitus, prediabetes and risk, disease progression of Parkinson's disease: A systematic review and meta-analysis.
Level 3 - non-randomized controlled study
Systematic review and meta-analysis of observational studies
PubMed 37009459 · doi:10.3389/fnagi.2023.1109914
What was done
A systematic review and meta-analysis of literature published before October 2022 was conducted using PubMed and Web of Science. The authors evaluated the association between diabetes mellitus (DM), prediabetes, and the risk and progression (motor and cognitive) of Parkinson's disease (PD). Pooled effect estimates were calculated as odds ratios (ORs), relative risks (RRs), or standardized mean differences (SMDs) using fixed- or random-effects models.
What was found
DM was associated with an increased risk of PD compared to non-diabetic controls (OR/RR = 1.23, 95% CI 1.12–1.35, I² = 90.4%, p < 0.001). Among patients with PD, co-morbid DM was associated with faster motor progression (RR = 1.85, 95% CI 1.47–2.34, I² = 47.3%, p = 0.091) and faster cognitive decline (OR/RR = 1.92, 95% CI 1.45–2.55, I² = 50.3%, p = 0.110). However, analysis of UPDRS III score change rates showed no statistically significant difference in motor progression (SMD = 2.58, 95% CI -3.11 to 8.27, I² = 99.9%, p < 0.001). Numerical findings for prediabetes were not reported in the abstract.
Why it matters
This review suggests that diabetes is linked to both a higher risk of developing Parkinson's disease and faster motor and cognitive deterioration in affected individuals.
Limits
The abstract does not state the total sample size, number of included studies, or specific results for prediabetes. There was extreme statistical heterogeneity across studies for PD risk (I² = 90.4%) and UPDRS III progression (I² = 99.9%), and observational designs are susceptible to confounding.
Cited by
- partial Having type 2 diabetes increases the risk of developing Parkinson's disease by 40%.