The association of telomere length and coronary heart disease: A systematic review and dose-response meta-analysis.

Aims: The association of telomere length (TL) and coronary heart disease (CHD) is still debated, and there is a lack of dose-response meta-analyses on this issue. The aim is therefore to integrate existing evidence on the association between TL and CHD risk and explore the dose-response relationship between them.

Data synthesis: PubMed, EMBASE, and Web of Science were searched for relevant studies up to September 2024. Meta-analysis was performed using a random-effects model, with data presented as RRs and 95 % CIs. Restricted cubic splines were used to assess linear and nonlinear associations. Subgroup analysis and meta-regression were performed to explore sources of heterogeneity. Fourteen articles (8 prospective cohort studies, 2 case-cohort studies, 2 case-control studies, and 2 cross-sectional studies) were finally included in the meta-analysis, with a total sample size of 199,562 participants and 25,752 cases. For CHD, the total RR for the highest TL group compared to the lowest TL group was 0.69 (95 % CI: 0.61, 0.78, I² = 64.5 %). For every 1 kilobase pair (kbp) increase in TL, the CHD risk decreased by 23 % (RR = 0.77, 95 % CI: 0.69, 0.87, I² = 89.0 %). The nonlinearity test indicated a linear association between TL and CHD risk (P_{non-linearity} = 0.930). Sensitivity analyses indicated that the results were robust.

Conclusions: The meta-analysis showed a linear relationship between TL and CHD. People with low TL may be more likely to develop CHD than those with high TL. The association between the two did not change in a wide range of populations.