0739 Effect of Obstructive Sleep Apnea and Insomnia on Cognitive Impairment in World Trade Center (WTC) Responders

Abstract

Abstract Introduction Mild Cognitive Impairment (MCI) is defined as a noticeable decline in cognitive abilities that doesn't interfere with daily activities; MCI may be a precursor of Alzheimer’s disease and related dementia. Elevated risk of MCI has been shown in subjects with obstructive sleep apnea (OSA) in a sleep clinic population and in subjects with insomnia in a general population. OSA and Insomnia both have a high prevalence among members of the World Trade Center Health Program General Responders’ Cohort (WTCHP GRC). Previous research indicated they had a high prevalence of MCI but did not examine sleep. We examined the association between MCI with OSA and/or Insomnia in the WTCHP GRC. Methods We assessed MCI by the Montreal Cognitive Assessment (MoCA) in English (n=115) and Spanish (n=27). MoCA < 26 defines MCI. OSA defined by AHI4>=5 or RDI>=15 events/hr, was assessed by home sleep test or in-lab NPSG. A score>7 on the Insomnia Severity Index (ISI) defined insomnia. Education was categorized as < or > bachelor’s (BA/BS) degree; subjects were categorized as Latino or not. Variables were analyzed using linear correlation, t-tests and chi-square tests as appropriate. Results The study population consisted of 142 subjects (80%M/20%F, age 58±8 years, BMI=29.7±5 kg/m2., Non-Latino/White=57%, Latino/any race=35%, < BA/BS=65%). OSA prevalence was 65.5% (mean AHI4=10.8±12.5/hr and RDI=21.42±16/hr). Insomnia prevalence was 48% (ISI=8.8 + 6). 48% (n=68) of subjects were classified as MCI. No correlation was observed between MoCA and OSA severity (r=0.1,p=0.24) or ISI (r=-0.1,p=0.1). Subjects without OSA had higher MCI prevalence (MCI_OSA=21.5% vs MCI_noOSA=37%, p=0.018). Lower educational level, race/ethnicity, and language (Spanish/English) (p< 0.001) were associated with MCI. Conclusion In this heterogenous cohort, we showed an unexpected lower MCI prevalence in OSA subjects. As shown by others, MCI defined by the MoCA was highly impacted by race/ethnicity, language and education. This suggests that our findings may be influenced by differences in the MoCA scoring and MCI cutoffs in Hispanic populations. To understand the relationship between MCI and sleep disorders in the WTC population, future studies should re-assess the cutoffs used in MoCA scoring or use tools to assess MCI less dependent on ethnicity and educational level. Support (if any) NIOSH/CDC U01OH011481, K24HL109156