Look AHEAD Sleep: Study Design and Baseline Characteristics

Abstract

AbstractBackgroundOlder adults with obesity (body mass index [BMI] ≥30 kg/m2) and type‐2 diabetes (T2D) have increased risks for mild cognitive impairment (MCI) and dementia. Sleep‐disordered breathing (SDB) is common in older adults and those with T2D and obesity, and has been linked to increased risk of Alzheimer’s disease (AD) and Alzheimer’s disease‐related dementias (ADRD). SDB may represent a unique and modifiable pathway that elevates the risk of cognitive decline among patients with T2D and obesity. Yet, few studies have examined associations between SDB and cognitive outcomes among persons with T2D and obesity. Addressing this gap is critical as the prevalence of metabolic disorders is increasing, placing a growing population at risk for MCI, and AD/ADRD. Look AHEAD Sleep (LA‐Sleep) was designed to study associations of SDB and circadian rhythms with cognitive function in older adults with a history of these conditions. Here, we report initial baseline characteristics of LA‐Sleep cohort.MethodParticipants enrolled in Look AHEAD Aging (LA‐A), a continuation of the Look AHEAD cohort study, were eligible to participate in LA‐Sleep. Participants completed cognitive assessments and were randomized to have a sleep assessment in either Year 1 (2022‐2023) or 2 (2023‐2024). Year 1 participants completed sleep questionnaires and received in‐home sleep assessment devices (WatchPAT and ActiGraph) and a sleep diary by mail.ResultOf 1,522 who consented to LA‐A, 952 agreed to LA‐Sleep and to date, 161 have provided year 1 WatchPAT (n = 161) or Actigraph (n = 107) data. There were more females (55.3%) than males; the average (±SD) age was 76.1±5.4 y; average BMI was 34.3±7.0; and 10.6% of the sample was Non‐Hispanic Black, 6.2% Hispanic, and 76.4% Non‐Hispanic White. Most had more than a high school education (90.1%). Of those with obesity in 2018‐2020, 20.0% had severe SDB (apnea hypopnea index ≥30). Overall mean actigraphic‐estimated sleep duration was 7.1±1.4 hours, sleep efficiency (total sleep time/time in bed) was 87.0%, and wake‐after‐sleep‐onset was 62.5±31.0 minutes/night.ConclusionAmong an older adult cohort with T2D and overweight or obesity, a high proportion of participants have severe SDB and high levels of sleep fragmentation, placing them at increased risk for cognitive impairment.