Dados do Trabalho

Título

Is obstructive sleep apnea associated with cognitive decline in seniors?

Introdução

The prevalence of obstructive sleep apnea (OSA) increases with age. Previous studies have shown an association between OSA and a higher risk of cognitive impairment in middle-aged adults. The OSA-related mechanisms involved in cognitive impairment may include sleep fragmentation, daytime sleepiness, oxidative stress, and metabolic dysfunction. Nonetheless, the role of the OSA on the pathogenesis of age-linked cognitive impairment remains unclear.

Objetivo

To determine whether OSA is associated with cognitive impairment in seniors.

Métodos

Independent adults aged 65 years or older previously screened for OSA performed a home sleep apnea testing. OSA was defined by an Apnea-Hypopnea Index (AHI) ≥5. Seniors included had their anthropometric information collected and their global cognitive function measured by the Mini-Mental State Examination (MMSE). A MMSE score≤26 indicated seniors with cognitive decline. Subjects with score>10 points in the Excessive Sleepiness Scale (ESS) were considered sleepy.

Resultados

In the study were included 296 seniors. The mean age was 71±5 years, 45% were men, mean BMI was 28.5±4.7 kg/m2, 34% scored>10 in the ESS, and 85% had OSA. Using MMSE were identified 106 seniors with cognitive decline. They had fewer years of schooling than those with MMSE >26. Among the seniors with OSA, 36% showed cognitive decline. The percentages of AHI<5 and AHI≥5 were similar in seniors with cognitive decline. Percentages of hypertension, diabetes, and psychiatric disorders were significantly greater in seniors with MMSE score≤26 than in seniors with MMSE >26. To predict MMSE score≤26, a multivariate binary logistic model was built adjusting for confounders from the following variables: female gender, age, BMI, AHI≥5, ESS>10, hypertension, diabetes, neurological disorder, and psychiatric disorder. The model with a Nagelkerke R square=0.19 showed the following significant associations: female gender (OR 2.37, CI 1.14-4.93), diabetes (OR 3.52, CI 1.39-8.92), and psychiatric disorder (OR 2.84, CI 1.18-6.81). The variable AHI≥5 was not associated with cognitive decline.

Conclusões

In the present study, OSA in seniors does not seem to be significantly associated with cognitive impairment measured by MMSE. The data demonstrated that diabetes is the strongest predictor of cognitive impairment, followed by psychiatric disorders and female gender.

Palavras-chave

obstructive sleep apnea, cognitive decline, seniors