The association of obstructive sleep apnea with blood and cerebrospinal fluid biomarkers of Alzheimer's dementia - A systematic review and meta-analysis.
Level 3 - non-randomized controlled study
Systematic review and meta-analysis of observational studies
PubMed 37245474 · doi:10.1016/j.smrv.2023.101790
What was done
Authors searched PubMed, Embase, and Cochrane Library for studies comparing blood and cerebrospinal fluid biomarkers of Alzheimer's disease between patients with obstructive sleep apnea (OSA) and healthy controls. Standardized mean differences were calculated using random-effects meta-analyses across 18 studies totaling 2,804 patients.
What was found
Compared to healthy controls, patients with OSA showed significantly lower cerebrospinal fluid amyloid beta-40 (SMD -1.13, 95% CI -1.65 to -0.60), higher blood total amyloid beta (SMD 0.68, 95% CI 0.40 to 0.96), higher blood amyloid beta-40 (SMD 0.60, 95% CI 0.35 to 0.85), higher blood amyloid beta-42 (SMD 0.80, 95% CI 0.38 to 1.23), and higher blood total-tau (SMD 0.664, 95% CI 0.257 to 1.072; I2 = 82%, p < 0.01, 7 studies).
Why it matters
This review provides quantitative evidence linking obstructive sleep apnea to altered amyloid and tau biomarker profiles, supporting sleep-disordered breathing as a potential contributor to Alzheimer's pathology.
Limits
All included data are observational and cannot establish causality. High statistical heterogeneity was present for tau markers (I2 = 82%). The abstract does not report whether analyses adjusted for key confounders such as age, body mass index, or APOE genotype, nor does it specify OSA severity thresholds.
Cited by
- supports Untreated sleep apnea is an established risk factor for neurodegeneration.