The decline in memory and cognition associated with disturbed breathing and long sleep has been modified by obesity and metabolic disorders, according to a study published in Alzheimer’s and Dementia.
The data comes from the Study of Latinos – Investigation of Neurocognitive Aging, which included Hispanic adults living in 4 cities in the United States between 2008 and 2011. Study participants were assessed for sociodemographic factors, sleep disorders, and neurocognitive status at baseline and at 7-year follow-up.
The study participants had an average age of 63 ± 8.1 years; 54.8% were women, 83.6% had taken sleeping pills in the last 4 weeks, 14.81% had a long sleep (> 9 hours per night), 6.43% had a short sleep (<6 hours per night) ) and 17% had a Respiratory Disease Event Index (REI) ³15. Respiratory events were reported as a reduction in airflow of at least 50% for at least 10 seconds with desaturations of at least 3%.
Memory performance was worst in people aged 65 and over with REI³15, long sleep duration and obesity (Delta, -1.58; SE, 0.38; P <0.001) or metabolic syndrome (Delta, -1.17; SE, 0, 38; P.). = .001). A similar pattern was found for processing speed in the elderly with high REI scores, long sleep periods, and obesity (Delta, -1.23; SE, 0.23; P <0.001) or metabolic syndrome (Delta, -1.24; SE , 0.25; P <.001). These individuals also showed more pronounced cognitive decline (obesity: delta -1.00; SE 0.42; P = 0.016; metabolic syndrome: delta -1.00; SE 0.42; P = 0.017).
In individuals aged 45 to 54 years, metabolic syndrome was observed to alter the relationship between sleep duration and REI for global cognition (P <0.001), processing speed (P = 0.003), and memory alteration (P = 0.021). In these 65 year olds and older, obesity was the modifier of global cognition (P <0.001), memory change (P <0.001), and the relationship between sleep duration and memory (P = 0.001).
A significant modifier for gender was observed for global cognition (P = .010). Women who did not have metabolic syndrome, slept late and REI ³15 showed the greatest decline in global cognitive function.
This study was limited by the use of self-reported sleep duration and the small amount of data available on sleep-related breathing disorders.
The study authors concluded that the relationship between sleep disordered breathing and cognition was altered by obesity and metabolic syndrome. More pronounced cognitive decline was found in middle-aged people without metabolic syndrome, as well as in older people with obesity.
Kaur SS, Tarraf W, Wu B, et al. Modification of signaling pathways by age and gender for the association between combined sleep-related breathing disorder and long sleep duration with neurocognitive decline in the Hispanic Community Health Study / Study of Latinos (HCHS / SOL). Alzheimer’s dementia. Published online on May 25, 2021. doi: 10.1002 / alz.12361
This article originally appeared on Psychiatry Advisor