A lifespan perspective on personality and health uncovers new causal pathways and provides a deeper, more nuanced approach to interventions. It is unproven that happiness is a direct cause of good health or that negative emotion, worry, and depression are significant direct causes of disease. Instead, depression-related characteristics are likely often reflective of an already-deteriorating trajectory. It is also unproven that challenging work in a demanding environment usually brings long-term health risks; on the contrary, individual strivings for accomplishment and persistent dedication to one's career or community often are associated with sizeable health benefits. Overall, a substantial body of recent research reveals that conscientiousness plays a very significant role in health, with implications across the lifespan. Much more caution is warranted before policy makers offer narrow health recommendations based on short-term or correlational findings. Attention should be shifted to individual trajectories and pathways to health and well-being.

Some individuals are prone to illness, decline, and premature mortality while others recover quickly, maintain health, and live long lives. Personality, an individual's biopsychosocial pattern of reactions and behaviors, is related to health across time, but the pathways are complex, with interrelated causal and non-causal links. Causal pathways linking personality and health include: health behaviors and habits; number and quality of social relationships; reactions to challenges and psychophysiological stress; and situation selection and evocation. Important but non-causal (spurious) links include: genes and early experiences; and disease-caused personality changes. Attending to the multiple links between personality and health within a lifespan perspective will aid causal understanding and facilitate the most appropriate interventions. © 2011 The Authors. Social and Personality Psychology Compass © 2011 Blackwell Publishing Ltd.

Objective

Sleep duration is known to significantly affect health in adults and children, but little is understood about long-term associations. This prospective cohort study is the first to examine whether childhood sleep duration is associated with lifelong mortality risk.

Method

Data from childhood were refined and mortality data collected for 1,145 participants from the Terman Life Cycle Study. Participants were born between 1904 and 1915, lived to at least 1940, and had complete age, bedtime, and waketime data at initial data collection (1917-1926). Homogeneity of the cohort sample (intelligent, mostly White) limits generality but provides natural control of common confounds. Through 2009, 1,039 participants had confirmed deaths. Sleep duration was calculated as the difference between each child's bed and wake times. Age-adjusted sleep (deviation from that predicted by age) was computed. Cox proportional hazards survival models evaluated childhood sleep duration as a predictor of mortality separately by sex, controlling for baseline age.

Results

For males, a quadratic relation emerged: Male children who underslept or overslept compared with peers were at increased risk of lifelong all-cause mortality (HR = 1.15, CIs [1.05, 1.27]). Effect sizes were smaller and nonsignificant in females (HR = 1.02, CIs [0.91, 1.14]).

Conclusions

Male children with shorter or longer sleep durations than expected for their age were at increased risk of death at any given age in adulthood. The findings suggest that sleep may be a core biobehavioral trait, with implications for new models of sleep and health throughout the entire life span.

Building upon decades of research with the lifelong (nine-decade) Terman Life Cycle Study, we present a life pathway model for understanding human thriving that accounts for long-term individual difference in health and longevity, with a particular focus on child personality and adult social relationships. Developing data derived and supplemented from the Terman study (N = 570 males, 451 females), we employed regression and survival analyses to test models of childhood personality predicting adult psychosocial factors (subjective well-being, family relationships, community involvement, subjective achievement, hardships) and subsequent longevity. Child personality differentially related to midlife social relationships, well-being, and hardships. Conscientiousness and good social relationships predicted longer life, whereas subjective well-being was unrelated to mortality risk. Examining multiple life factors across long time periods uncovers important pathways through which personality relates to premature mortality or longevity. Typical stress-and-illness models are untenable and should be replaced with life span trajectory approaches.

Conscientiousness has been shown to predict healthy behaviors, healthy social relationships, and physical health and longevity. The causal links, however, are complex and not well elaborated. Many extant studies have used comparable measures for conscientiousness, and a systematic endeavor to build cross-study analyses for conscientiousness and health now seems feasible. Of particular interest are efforts to construct new, more comprehensive causal models by linking findings and combining data from existing studies of different cohorts. Although methodological perils can threaten such integration, such efforts offer an early opportunity to enliven a life course perspective on conscientiousness, to see whether component facets of conscientiousness remain related to each other and to relevant mediators across broad spans of time, and to bolster the findings of the few long-term longitudinal studies of the dynamics of personality and health. A promising approach to testing new models involves pooling data from extant studies as an efficient and heuristic prelude to large-scale testing of interventions.

The present study used a collaborative framework to integrate 2 long-term prospective studies: the Terman Life Cycle Study and the Hawaii Personality and Health Longitudinal Study. Within a 5-factor personality-trait framework, teacher assessments of child personality were rationally and empirically aligned to establish similar factor structures across samples. Comparable items related to adult self-rated health, education, and alcohol use were harmonized, and data were pooled on harmonized items. A structural model was estimated as a multigroup analysis. Harmonized child personality factors were then used to examine markers of physiological dysfunction in the Hawaii sample and mortality risk in the Terman sample. Harmonized conscientiousness predicted less physiological dysfunction in the Hawaii sample and lower mortality risk in the Terman sample. These results illustrate how collaborative, integrative work with multiple samples offers the exciting possibility that samples from different cohorts and ages can be linked together to directly test life span theories of personality and health.

Markers of executive functioning, such as prudent planning for the future and impulse control, are related to conscientiousness and may be central to both occupational success and health outcomes. The aim of the study was to examine relations among conscientiousness, career success, and mortality risk across a 65-year period. Using data derived from 693 male participants in the Terman Life Cycle Study, we examined associations among childhood personality, midlife objective career success, and lifelong mortality risk through 2006. Conscientiousness and career success each predicted lower mortality risk (N = 693, relative hazard (rh) = 0.82 [95% confidence interval = 0.74, 0.91] and rh = 0.80 [0.71, 0.91], respectively), with both shared and unique variance. Importantly, childhood personality moderated the success–longevity link; conscientiousness was most relevant for least successful individuals. Conscientiousness and career success predicted longevity, but not in a straightforward manner. Findings highlight the importance of lifespan processes.