For how we live.
Nigerian adults scored well below US and Norwegian comparison samples on a six-dimension sleep health measure. In South Africa, students with backup power were far less likely to report worse sleep during outages.
Twenty months of under-mattress sensor data from 95,819 people found that chronic irregularity was common, persistent, and tracked with 46% higher odds of hypertension.
A 327-person survey of economically distressed Eastern Kentucky counties found insomnia prevalence ranged from 44% to 83% depending on income alone.
Age, sex, employment and socioeconomic level together explained under 1% of variance in insomnia severity. Perceived stress and generalised anxiety explained close to a third.
Across 20,121 adults and 25 years of registry data, morningness markers predicted lower educational attainment but also lower odds of the bottom income quintile. Effects were absent in women.
Applying prevalence figures to UN population data yields 852 million adults with insomnia. Only 31 of 237 countries had a usable national estimate of their own.