Neuroticism in China: Massive Biobank Study Links Personality to Heart and Mental Disease

Neuroticism, the personality trait that predisposes people to worry, moodiness and emotional volatility, has long been studied almost exclusively in Western populations. Now one of the largest investigations ever conducted in Asia has mapped how the trait is distributed across Chinese society and, more strikingly, how it shapes the future health of the people who carry it. Drawing on 25,041 adults enrolled in the China Kadoorie Biobank, researchers report that neuroticism follows a clear sociodemographic gradient in China and that people with elevated scores face measurably higher risks of heart disease, stroke, mental disorders and diseases of the nervous and digestive systems over subsequent years of follow-up.

The study, published in BMC Public Health by Ruixin He of Shanghai Jiao Tong University School of Medicine and colleagues at the University of Oxford and Peking University, took advantage of the second resurvey of the China Kadoorie Biobank, conducted in 2013 and 2014. Participants were drawn from five urban and five rural regions of China, an unusually broad geographic and social spread for personality research. Neuroticism was measured with the 23-item Eysenck Personality Questionnaire, a classic psychometric instrument in which respondents answer yes-or-no questions about mood, worry and emotional reactivity. Answers were converted into a neuroticism score, or N-score, ranging from 0 to 23, with higher values indicating a stronger tendency toward anxiety, irritability and emotional instability.

The average N-score in the cohort was 2.52, a comparatively low figure that the authors interpret in light of cultural and response-style differences. Yet the patterning across the population was anything but flat. Women scored higher than men on average, and urban residents scored higher than their rural counterparts. Perhaps most intriguingly, the trait showed a pronounced downward trend with age: older participants reported consistently fewer neurotic symptoms than younger ones. This age gradient echoes findings from Western cohorts and supports the idea of a maturational curve in emotional stability, in which people tend to become calmer and more resilient as they move through adulthood, though longitudinal data would be needed to confirm that individuals actually decline in neuroticism rather than the pattern reflecting generational differences.

Socioeconomic circumstances left an equally strong fingerprint on the trait. Higher N-scores were strongly associated with social disadvantage: participants who were not married and those from households with lower incomes scored significantly higher than their wealthier, married peers. The relationship between neuroticism and deprivation is almost certainly bidirectional. Chronic financial stress and social isolation can heighten emotional reactivity, while a temperament prone to worry and distress can undermine relationships, job performance and economic advancement. Disentangling cause from consequence in such data is notoriously difficult, but the consistency of the association across a cohort of this size strengthens the case that personality and social position are deeply intertwined.

The cross-sectional health findings were dramatic. Compared with participants who scored zero on the neuroticism scale, those with an N-score of 4 or higher showed substantially higher prevalence of mental health problems and poor self-rated general health, with adjusted risk ratios ranging from 1.52 to 41.01 depending on the condition examined. The upper end of that range reflects the near-universal co-occurrence of very high neuroticism scores with certain psychological conditions, which is expected given that the trait itself measures emotional distress. Even the more conservative end of the range, however, indicates a meaningful excess burden of psychological suffering among people with elevated scores, reinforcing the trait’s status as one of the most robust psychological predictors of mental ill health.

What elevates the study above a simple snapshot is its prospective component. By linking participants to electronic health registries, the researchers tracked who went on to develop major diseases after the personality assessment. Using Cox regression models that adjusted for confounding factors, they found that people in the highest neuroticism category had significantly higher risks of several serious conditions than those in the lowest category, with hazard ratios between 1.17 and 1.81. The list of affected outcomes is strikingly broad: ischaemic heart disease, stroke, mental and behavioural disorders, and diseases of the nervous system and digestive system all appeared at elevated rates among highly neurotic participants.

The cardiovascular findings deserve particular attention because they speak to a long-standing debate in psychosomatic medicine. Proposed mechanisms run along several plausible pathways. Chronically heightened emotional reactivity is associated with sustained activation of the hypothalamic-pituitary-adrenal axis and the sympathetic nervous system, which can raise blood pressure, promote inflammation and disturb metabolic regulation. People high in neuroticism are also more likely to smoke, sleep poorly, remain sedentary and neglect medical care, behaviours that mediate part of the observed risk. The digestive system association is similarly biologically credible, given the dense neural communication between the gut and the brain and the established role of stress in functional gastrointestinal disorders.

The authors are careful to frame their results as associations rather than proof of causation. Reverse causation remains a possibility, since subclinical disease may itself heighten emotional distress, and residual confounding by unmeasured lifestyle or environmental factors cannot be excluded. Nevertheless, the sheer scale and diversity of the China Kadoorie Biobank, combined with registry-based outcome ascertainment, give the findings a weight that smaller clinic-based studies cannot match. The work also fills a conspicuous gap: most large-scale personality epidemiology has been conducted in Europe and North America, and it was genuinely uncertain whether the trait’s health correlates would replicate in a population with very different cultural norms around expressing emotion and answering questionnaire items.

The replication appears to have succeeded, and that has practical implications. If neuroticism reliably flags elevated risk for cardiometabolic and psychiatric disease in Chinese adults, it could in principle be incorporated into risk stratification tools, helping clinicians identify patients who might benefit from closer monitoring, stress-management interventions or earlier mental health support. The sociodemographic patterning adds another layer: because elevated scores cluster among people who are unmarried, poorer and, in some respects, already vulnerable, the trait may serve as a marker for compounded disadvantage, concentrating both psychological and physical health burdens in specific segments of the population.

For a trait once dismissed as a mere questionnaire curiosity, neuroticism is emerging as a genuine public health variable. The China Kadoorie Biobank analysis suggests that the emotional temperament of a population is not evenly distributed, that it tracks social circumstances closely, and that it foreshadows disease outcomes ranging from heart attacks to digestive disorders. As biobanks worldwide continue to link psychological measurements to long-term health records, the question is shifting from whether personality matters for health to how best to translate that knowledge into prevention. For the tens of millions of people worldwide who sit at the anxious end of the neuroticism spectrum, the new evidence offers both a warning and, potentially, an early opportunity for intervention.

Subject of Research: Sociodemographic patterns and disease associations of neuroticism in Chinese adults

Article Title: Patterns and health relevance of neuroticism in Chinese men and women: evidence from the China Kadoorie Biobank

Article References: He, R., Du, H., Clarke, J., Wang, B., Yang, L., Pei, P., Sun, D., Lv, J., Yu, C., Yang, X., Sun, X., Chen, J., Li, L., Chen, Z., Chen, Y., for the China Kadoorie Biobank Collaborative Group, Clarke, R., Collins, R., Peto, R., … Qu, C. (2026). Patterns and health relevance of neuroticism in Chinese men and women: evidence from the China Kadoorie Biobank. BMC Public Health. https://doi.org/10.1186/s12889-026-29670-6

Image Credits: AI Generated

DOI: 10.1186/s12889-026-29670-6

Keywords: neuroticism, China Kadoorie Biobank, personality, mental health, ischaemic heart disease, stroke, Eysenck Personality Questionnaire, epidemiology, public health, socioeconomic status, cohort study, psychometrics