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.