Early-life exposure to famine and late-life depression: Does leukocyte telomere length mediate the association?

BACKGROUND: A positive association between early-life famine exposure and depression has been demonstrated. However, the mechanisms by which famine exposure in early life leads to late-life depression remains unclear. The present study examines the impact of leukocyte telomere length (LTL) and/or religiosity on the relationship between early-life famine exposure and late-life depression in a Chinese minority sample. METHODS: A cross-sectional study of community-dwelling adults aged 55 or older was conducted in the Ningxia province of western China from 2013 to 2016. Multivariate ordinal logistic regression was used to examine the association between famine exposure and depression status, and a series mediation model was constructed to identify the mediation role of LTL and religiosity. RESULTS: Compared with famine exposure during adulthood, fetal famine exposure was associated with a higher risk of late-life depression (adjusted odds ratio of 3.17, 95% CI: 1.36-7.38). A cumulative effect of fetal famine exposure on the risk of late-life depression was observed. Participants born in 1961 (the third year of the famine) had the strongest association with late-life depression. LTL played a mediating role in the association between famine exposure and depression which accounted for 21% of the total effect. LIMITATIONS: The cross-sectional design prevents causal inferences regarding the relationships between famine and depression. CONCLUSIONS: Fetal famine exposure was associated with an increased risk of late-life depression in a Chinese minority community-dwelling population. Telomere shortening partially mediated this association.

Religiosity and Telomere Length: Moderating Effect of Religiosity on the Relationship Between High-Risk Polymorphisms of the Apolipoprotein E and TOMM40 Gene and Telomere Length.

Objective: The current study seeks to examine the relationship between religiosity and telomere length (TL) in an older Chinese Muslim sample and to explore the moderating effect of religiosity on the relationship between high-risk polymorphisms and TL. Methods: A cross-sectional study of 1,692 community-dwelling adults aged 55 or older was conducted. Apolipoprotein E and TOMM40 (rs2075650) gene polymorphisms and TL were determined using standard procedures. Ordinal logistic regression was used to examine the associations. Results: Religiosity was significantly and positively related to TL. A significant interaction emerged between religiosity and the rs2075650 G polymorphism in predicting TL. Stratified multivariate analyses demonstrated that the relationship between the rs2075650 G state and TL was particularly strong among those who were more religious, as hypothesized. Conclusion: The findings revealed that religiosity may influence cellular aging in part by modifying the effect that high-risk genes have on increasing vulnerability to dementia and cognitive impairment.

Religion, Purpose in Life, Social Support, and Psychological Distress in Chinese University Students.

We examined the relationship between religious involvement and psychological distress and explored the mediating effects of social support and purpose in life in university students in western, mid-western, and eastern China. Cross-sectional survey of a representative sample of 1812 university students was conducted. The Purpose in Life scale, Duke Social Support Index, and Religious Commitment Inventory-10 were administered, along with Kessler's Psychological Distress Scale. Structural equation modeling was used to test two models of the mediation hypothesis, examining direct, indirect, and total effects. Model 1 (with direction of effect hypothesized from religiosity to psychological distress) indicated that religious involvement had a direct effect on increasing psychological distress (ß = 0.23, p < .01) with minor mediated effects. However, Model 2 (with direction of effect hypothesized from psychological distress to religiosity) indicated strong indirect protective effects of religiosity on psychological distress through purpose in life and social support (ß = -.40, p < .01). The findings are consistent with the hypothesis that psychological distress increases religious involvement, which then increases purpose in life and social support that then lead to lower psychological distress.