Obstructive sleep apnea treatment and dementia risk in older adults

Study Objectives: To examine associations between positive airway pressure (PAP) therapy, adherence and incident diagnoses of Alzheimer's disease (AD), mild cognitive impairment (MCI), and dementia not otherwise specified (DNOS) in older adults. Methods: This retrospective study utilized Medicare 5% fee-for-service claims data of 53,321 beneficiaries, aged 65 and older, with an obstructive sleep apnea (OSA) diagnosis prior to 2011. Study participants were evaluated using ICD-9 codes for neurocognitive syndromes (AD [n = 1,057], DNOS [n = 378], and MCI [n = 443]) that were newly identified between 2011 and 2013. PAP treatment was defined as the presence of at least one durable medical equipment (Healthcare Common Procedure Coding System [HCPCS]) code for PAP supplies. PAP adherence was defined as at least two HCPCS codes for PAP equipment, separated by at least 1 month. Logistic regression models, adjusted for demographic and health characteristics, were used to estimate associations between PAP treatment or adherence and new AD, DNOS, and MCI diagnoses. Results: In this sample of Medicare beneficiaries with OSA, 59% were men, 90% were non-Hispanic whites and 62% were younger than 75 years. The majority (78%) of beneficiaries with OSA were prescribed PAP (treated), and 74% showed evidence of adherent PAP use. In adjusted models, PAP treatment was associated with lower odds of incident diagnoses of AD and DNOS (odds ratio [OR] = 0.78, 95% confidence interval [95% CI]: 0.69 to 0.89; and OR = 0.69, 95% CI: 0.55 to 0.85). Lower odds of MCI, approaching statistical significance, were also observed among PAP users (OR = 0.82, 95% CI: 0.66 to 1.02). PAP adherence was associated with lower odds of incident diagnoses of AD (OR = 0.65, 95% CI: 0.56 to 0.76). Conclusions: PAP treatment and adherence are independently associated with lower odds of incident AD diagnoses in older adults. Results suggest that treatment of OSA may reduce the risk of subsequent dementia.