Energy poverty (EPOV), defined as the lack of access to adequate, affordable, reliable, and safe energy services, is a significant global issue with far-reaching consequences. While the detrimental effects of EPOV on overall health are well-documented, research on its impact on cognitive and mental health (CMH) remains limited, particularly among aging populations. This is crucial given the increasing proportion of older adults globally and the importance of CMH for healthy aging. China, with its rapidly aging population and challenges related to EPOV, presents an ideal context for investigating this relationship. This study addresses this gap by exploring the impact of EPOV on CMH in middle-aged and older adults in China, utilizing a rich dataset and diverse measures of EPOV.

The concept of EPOV has evolved since its initial articulation in 1982, with current definitions encompassing multiple dimensions of energy access and affordability. While several studies have explored the link between EPOV and overall health, direct evidence of its impact on CMH is scarce. Some indirect evidence suggests a negative correlation between EPOV and academic achievement (a measure of cognitive function), and also between EPOV and subjective well-being (related to mental health). The literature also extensively supports the negative effect of EPOV on physical health (PH), a factor that might mediate the relationship between EPOV and CMH. Existing studies often utilize a single measure of EPOV; this study offers a unique perspective by employing six distinct measures, encompassing energy affordability thresholds, to enhance the robustness of the findings. Notably, the study focuses on energy affordability, a more relevant aspect given the near-universal access to electricity in China.

This study utilizes data from the China Family Panel Studies (CFPS), a nationally representative survey, spanning the years 2014, 2016, and 2018. The sample is restricted to individuals aged 45 and above, focusing on the middle-aged and older adult population. Six distinct measures of EPOV are constructed based on energy affordability, considering different income thresholds and regional variations. Cognitive health (CH) is primarily measured using a self-reported memory score, while mental health (MH) is assessed using six indicators from the CES-D scale. Physical health (PH) is proxied by self-reported health status. A two-way fixed-effects (FE) model is employed to estimate the impact of EPOV on CMH, controlling for several individual-level factors such as age, gender, education, and employment status. Two-stage least squares (2SLS) estimation, with the provincial average of EPOV as an instrumental variable, addresses potential endogeneity concerns. Robustness checks are conducted using alternative EPOV measures and CMH proxies. A mediation analysis examines the role of PH in the EPOV-CMH relationship. Finally, a subgroup analysis explores the heterogeneous effects of EPOV on middle-aged and older adults.

The study reveals that the proportion of middle-aged and older adults experiencing EPOV in China ranges from 24.3% to 27.8%, depending on the EPOV measure used. Baseline OLS and FE regression results consistently show a significantly negative association between EPOV and both CH and MH. 2SLS and FE-IV estimations, designed to mitigate endogeneity, confirm this negative association and suggest that the baseline estimates are downward biased. Robustness checks using different EPOV measures and alternative CMH proxies (happiness, life satisfaction, math and verbal test scores) reinforce these findings. The mediation analysis demonstrates that PH significantly mediates the relationship between EPOV and CMH. The lagged-effect analysis suggests that EPOV's negative impact on CMH persists over time. Finally, subgroup analysis shows that the negative impact of EPOV is statistically significantly stronger among older adults than among the middle-aged, particularly for mental health. The spatial distribution of EPOV is also examined, revealing regional disparities and a general downward trend over the study period.

The findings of this study demonstrate a significant negative impact of EPOV on both cognitive and mental health among middle-aged and older adults in China. This impact is particularly pronounced in older adults, highlighting their vulnerability to energy insecurity. The mediating role of physical health emphasizes the multifaceted nature of this relationship. The persistent effects of EPOV over time underscores the importance of sustained interventions. The results contribute to the growing body of evidence highlighting the social and health consequences of EPOV, beyond its immediate economic implications. The findings have significant policy implications for China and other countries facing similar challenges, underscoring the need for comprehensive strategies that address energy affordability and promote healthy aging.

This study contributes significantly to the understanding of EPOV's impact on CMH among middle-aged and older adults in China by utilizing a nationally representative dataset and multiple EPOV measures. The findings consistently indicate a significant negative relationship, mediated by PH, with a stronger effect on older adults. Future research could explore the specific mechanisms underlying this relationship, investigate the effectiveness of targeted interventions, and examine the long-term health consequences of EPOV.

The study relies on self-reported measures of health, which may be subject to recall bias. The cross-sectional nature of the data limits the ability to establish definitive causal relationships. Future research could employ longitudinal data to better understand the dynamics between EPOV and CMH. Also, the study primarily focuses on energy affordability, neglecting other dimensions of energy poverty.