The United Nations recently released population projections based on data until 2012 and a Bayesian probabilistic methodology. Analysis of these data reveals that, contrary to previous literature, world population is unlikely to stop growing this century. There is an 80% probability that world population, now 7.2 billion, will increase to between 9.6 and 12.3 billion in 2100. This uncertainty is much smaller than the range from the traditional UN high and low variants. Much of the increase is expected to happen in Africa, in part due to higher fertility and a recent slowdown in the pace of fertility decline. Also, the ratio of working age people to older people is likely to decline substantially in all countries, even those that currently have young populations.The United Nations (UN) is the leading agency that projects world population into the future on a regular basis (2). Every two years it publishes revised data of the populations of all countries by age and sex, as well as fertility, mortality and migration rates, in a biennial publication called the World Population Prospects (WPP). In July 2014, probabilistic projections for individual countries to 2100 were released Unlike previous projections, they allow us to quantify our confidence in projected future trends using established methods of statistical inference. They are based on recent data, including the results of the 2010 round of censuses and recent surveys until 2012, as well as the most recent data on incidence, ‡

a b s t r a c tThe plant hormone abscisic acid (ABA) triggers production of reactive oxygen species (ROS) in guard cells via the AtrbohD and AtrbohF NADPH oxidases, leading to stomatal closure. The ABA-activated SnRK2 protein kinase open stomata 1 (OST1) (SRK2E/SnRK2.6) acts upstream of ROS in guard cell ABA signaling. Here, we report that OST1 phosphorylates Ser13 and Ser174 on AtrbohF. In addition, substitution of Ser174 to Ala results in a $40% reduction in the phosphorylation of AtrbohF by OST1. We also show that OST1 physically interacts with AtrbohF. These results provide biochemical evidence suggesting that OST1 regulates AtrbohF activity.

Age, sex, ethnicity, urban-rural residence, economic condition, religious involvement, and daily exercise are significantly associated with levels of frailty. Hazard analyses further reveal that the FI is a robust predictor of mortality at advanced ages and that the relationship between frailty and mortality is independent of various covariates. Discussion The measurement and analysis of frailty have broad implications for public health initiatives designed to target individuals with the diminished capacity to effectively compensate for external stressors and to prevent further declines associated with aging and mortality. A key to healthy longevity is the prevention, postponement, and potential recovery from physical and cognitive deficits at advanced ages through enhanced medical interventions and treatments.

BackgroundStudies have shown that inadequate access to healthcare is associated with lower levels of health and well-being in older adults. Studies have also shown significant urban-rural differences in access to healthcare in developing countries such as China. However, there is limited evidence of whether the association between access to healthcare and health outcomes differs by urban-rural residence at older ages in China.MethodsFour waves of data (2005, 2008/2009, 2011/2012, and 2014) from the largest national longitudinal survey of adults aged 65 and older in mainland China (n = 26,604) were used for analysis. The association between inadequate access to healthcare (y/n) and multiple health outcomes were examined—including instrumental activities of daily living (IADL) disability, ADL disability, cognitive impairment, and all-cause mortality. A series of multivariate models were used to obtain robust estimates and to account for various covariates associated with access to healthcare and/or health outcomes. All models were stratified by urban-rural residence.ResultsInadequate access to healthcare was significantly higher among older adults in rural areas than in urban areas (9.1% vs. 5.4%; p < 0.01). Results from multivariate models showed that inadequate access to healthcare was associated with significantly higher odds of IADL disability in older adults living in urban areas (odds ratio [OR] = 1.58–1.79) and rural areas (OR = 1.95–2.30) relative to their counterparts with adequate access to healthcare. In terms of ADL disability, we found significant increases in the odds of disability among rural older adults (OR = 1.89–3.05) but not among urban older adults. Inadequate access to healthcare was also associated with substantially higher odds of cognitive impairment in older adults from rural areas (OR = 2.37–3.19) compared with those in rural areas with adequate access to healthcare; however, no significant differences in cognitive impairment were found among older adults in urban areas. Finally, we found that inadequate access to healthcare increased overall mortality risks in older adults by 33–37% in urban areas and 28–29% in rural areas. However, the increased risk of mortality in urban areas was not significant after taking into account health behaviors and baseline health status.ConclusionsInadequate access to healthcare was significantly associated with higher rates of disability, cognitive impairment, and all-cause mortality among older adults in China. The associations between access to healthcare and health outcomes were generally stronger among older adults in rural areas than in urban areas. Our findings underscore the importance of providing adequate access to healthcare for older adults—particularly for those living in rural areas in developing countries such as China.

Our findings suggest that socioeconomic environment throughout the life course, early life in particular, can influence the risk of cognitive impairment in old age. Not only can public policy that targets illiteracy, hunger, and poverty improve the lives of tens of thousands of children, but ultimately such investments will pay significant dividends many decades later in enhancing the cognitive well-being of older persons.

Study Objectives: To examine factors associated with self-reported sleep quality and duration among very old adults in China. Design: Cross-sectional analysis of the 2005 wave of the Chinese Longitudinal Healthy Longevity Survey (CLHLS). Setting: In-home interview with older adults in 22 provinces in mainland China. Participants: A total of 15,638 individuals aged 65 and older (5,047 aged 65-79, 3,870 aged 80-89, 3,927 aged 90-99, and 2,794 aged 100 and older, including 6,688 men and 8,950 women). Interventions: N/A Measurements and Results: Two self-reported sleep questions together with numerous sociodemographic and health status measures were used in this study. Sixty-five per cent of Chinese elders reported good quality of sleep. The average number of self-reported hours of sleep was 7.5 (SD 1.9), with 13.1%, 16.2%, 18.0%, 28.0%, 9.2%, and 15.5% reporting ≤ 5, 6, 7, 8, 9, and ≥ 10 hours, respectively (weighted). Multivariate analyses showed that male gender, rural residence, Han ethnicity, higher socioeconomic status, and good health conditions were positively associated with good quality of sleep. All other factors being equal, octogenarians, nonagenarians, and centenarians were more likely to have good sleep quality than the young elders aged 65-79. Elders with poorer health status or older age were more likely to have either relatively shorter (≤ 6 h) or longer (≥ 10 h) sleep duration. Married elders were more likely to have an average duration between these two values. Except for some geographic variations, associations between all other factors and sleep duration were weak compared to the effects of health. Conclusions: Age and health conditions are the two most important factors associated with self-reported sleep quality and duration. Good quality of sleep among long-lived old adults may have some implications for achieving healthy longevity. A commentary on this article appears in this issue on page 575.

Based on unique data from the largest-ever sample of the Chinese oldest-old aged 80 and older, our multivariate logistic regression analyses show that either receiving adequate medical service during sickness in childhood or never/rarely suffering from serious illness during childhood significantly reduces the risk of being ADL (activities of daily living) impaired, being cognitively impaired, and self-reporting poor health by 18%–33% at the oldest-old ages. Estimates of effects for five other indicators of childhood conditions are similarly positive but mostly not statistically significant. Multivariate survival analysis shows that better childhood socioeconomic conditions in general tend to reduce the four-year period mortality risk among the oldest-old. But after additional controls for 14 covariates are put into the model, the effects are not statistically significant, thus suggesting that most of the effects of childhood conditions on oldest-old mortality are indirect—at least to the point of affecting current health status at the oldest-old ages, which itself is strongly associated with mortality. While acknowledging limitations of the present analyses due to a lack of information on childhood illness, the oldest-olds’ recollection errors, and other data problems, we conclude, based on this and other studies, that policies that enhance childhood health care and children’s socioeconomic wellbeing can have large and long-lasting benefits up to the oldest-old ages.

Using a large, nationally representative longitudinal sample of Chinese aged 65 and older, this study examines the effects of childhood, adult, and community socioeconomic conditions on mortality and several major health outcomes. The role of social mobility is also tested. We find that childhood socioeconomic conditions exert long-term effects on functional limitations, cognitive impairment, self-rated health, and mortality independent of adult and community socioeconomic conditions. Achieved conditions matter for most outcomes as well, considering that adult and community socioeconomic conditions have additional impacts on health among Chinese elders. The majority of the effects of childhood conditions are not mediated by adult and community conditions. The results also show that social mobility and health in later life are linked in complex ways and that psychosocial factors have marginal explanatory power for the effects of socioeconomic conditions. Overall, this study provides new longitudinal evidence from China to support the notion that health and mortality at older ages are influenced by long-term and dynamic processes structured by the social stratification system. We discuss our findings in the context of the life course and ecological perspective, emphasizing that human development is influenced by a nexus of social experiences that impact individuals throughout life.