Reduced Neurobehavioral Impairment from Sleep Deprivation in Older Adults: Contribution of Adenosinergic Mechanisms

A night without sleep is followed by enhanced sleepiness, increased low-frequency activity in the waking EEG, and reduced vigilant attention. The magnitude of these changes is highly variable among healthy individuals. Findings in young men of low and high subjective caffeine sensitivity suggest that adenosinergic mechanisms contribute to inter-individual differences in sleep deprivation-induced changes in EEG theta activity, as well as optimal performance on the psychomotor vigilance task (PVT). In comparison to young subjects, healthy adults of older age typically feel less sleepy after sleep deprivation, and show fewer response lapses, and faster reaction times on the PVT, especially in the morning after the night without sleep. We hypothesized that age-related changes in adenosine signal transmission underlie reduced vulnerability to sleep deprivation in older individuals. To test this hypothesis, the combined effects of prolonged wakefulness and the adenosine receptor antagonist, caffeine, on an antero-posterior power gradient in EEG theta activity and PVT performance were analyzed in healthy older and caffeine-insensitive and -sensitive young men. The results show that age-related differences in sleep loss-induced changes in brain rhythmic activity and neurobehavioral functions are mirrored in young individuals of low and high sensitivity to the stimulant effects of caffeine. Moreover, the effects of sleep deprivation and caffeine on regional theta power and vigilant attention are inversely correlated across older and young age groups. Genetic variants of the adenosine A2A receptor gene contribute to individual differences in neurobehavioral performance in rested and sleep deprived state, and modulate the actions of caffeine in wakefulness and sleep. Based upon this evidence, we propose that age-related differences in A2A receptor-mediated signal transduction could be involved in age-related changes in the vulnerability to acute sleep deprivation

Marital Dissolutions and Changes in Mental Health: Evidence from Rural Malawi

Family demographers conducting research in high-income countries have long examined the link between multiple dimensions of marital dissolutions—including discrete events and marital histories—and adverse health outcomes. Research on the relationship between marital dissolutions, marital histories, and health among older adults in sub-Saharan Africa is comparatively limited, and less empirically developed, despite marriage being a paramount cultural and life-course marker on the African continent. Using fixed-effects regressions and 2012 data from the Mature Adults Cohort of the Malawi Longitudinal Study of Families and Health (MLSFH-MAC) linked back to cohort information from 2008 and 2010 available through MLSFH, we test how changes in different dimensions of marital dissolutions are associated with changes in mental health among nearly 1200 respondents, in addition to the potential moderating effects of household savings and region of residence. For men, spending more of one’s life outside of marriage is associated with worse mental health, while more marital dissolutions are surprisingly linked to better mental health for women

Aging and Hypertension among the Global Poor—Panel Data Evidence from Malawi

Background: Hypertension has a rapidly growing disease burden among older persons in low-income countries (LICs) that is often inadequately diagnosed and treated. Yet, most LIC research on hypertension is based on cross-sectional data that does not allow inferences about the onset or persistence of hypertension, its correlates, and changes in hypertension as individuals become older. Data and methods: The Mature Adults Cohort of the Malawi Longitudinal Study of Families and Health (MLSFH-MAC) is used to provide among the first panel analyses of hypertension for older individuals in a sub-Saharan LIC using blood pressure measurements obtained in 2013 and 2017. Findings: High blood pressure is very common among mature adults aged 45+ in rural Malawi, and hypertension is more prevalent among older as compared to middle-aged respondents. Yet, in panel analyses for 2013-17, we find no increase in the prevalence of hypertension as individuals become older. Hypertension often persists over time, and the onset of hypertension is predicted by factors such as being overweight/obese, or being in poor physical health. Otherwise, however, hypertension has few socioeconomic predictors. There is also no gender differences in the level, onset or persistence in hypertension. While hypertension is associated with several negative health or socioeconomic consequences in longitudinal analyses, cascade-of-care analyses document significant gaps in the diagnosis and treatment of hypertension. Conclusions: Our findings indicate that hypertension and related high cardiovascular risks are widespread, persistent, and often not diagnosed or treated in this rural sub-Saharan population of older individuals. Prevalence, onset and persistence of hypertension are common across all subgroups-including, importantly, both women and men. While age is an important predictor of hypertension risk, even in middle ages 45-55 years, hypertension is already widespread. Hypertension among adults aged 45+ in Malawi is thus more similar to a generalized epidemic than in high-income countries where cardiovascular risk has strong socioeconomic gradients and untreated hypertension particularly prevalent in vulnerable subsets of older persons

Health Screening for Emerging and Non-Communicable Disease Burdens Among the Global Poor

Among adults in rural Malawi, population health screening for high blood pressure (BP) led to a 22-percentage point drop in the likelihood of being hypertensive four years later. Individuals with elevated BP received a referral letter upon initial screening; at follow-up, they had lower BP and higher self-reported mental health than individuals with similar BP who were just below the threshold for referral. Population health screenings can reduce the burden of non-communicable diseases in low-income countries

Health Screening for Emerging Disease Burdens Among the Global Poor

Evidence for the effectiveness of population health screenings to reduce the burden of non-communicable diseases in low income countries remains very limited. We investigate the sustained effects of a health screening in Malawi where individuals received a referral letter if they had elevated blood pressure. Using a regression discontinuity design and a matching estimator, we find that receiving a referral letter reduced blood pressure and the probability of being hypertensive by about 22 percentage points four years later. These lasting effects are explained by a 20 percentage points increase in the probability of being diagnosed with hypertension. There is also evidence of an increase in the uptake of medication, while we do not identify improvements in hypertension-related knowledge or risk behaviors. The health screening had some positive effects on mental health. Overall, this study suggests that population-based hypertension screening interventions are an effective tool to improve health in low-income contexts

Mortality Risk Information, Survival Expectations and Sexual Behaviors

Individuals in low-income settings are often overly pessimistic about their own survival, suggesting that better knowledge about survival risks might encourage investments in health. This paper provides evidence from a randomized experiment that provided mature adults aged 45+ in Malawi with information about mortality risks. Treated individuals are less likely to engage in risky sexual practices one year after the intervention, and they increase other forward-looking behaviors such as investments in agriculture. Expectations of HIV+ people living longer, which makes the pool of potential partners riskier, are a primary driver of reduced sexual risk taking in response to the intervention