LONGER LEUCOCYTE TELOMERE LENGTH PROTECTS FROM ADVERSE CARDIOVASCULAR EFFECTS OF PROLONGED AIR POLLUTION EXPOSURE

Objective: Higher air pollution exposure and shorter leukocyte telomere length (LTL) are both associated with increased risk of cardiovascular disease. In this study we tested whether effects of prolonged higher air pollution exposure on cardiovascular health can be mediated through LTL decrease or if LTL and air pollution exposure can have interacting effects on cardiovascular state. Design and method: In this cross-sectional analysis we selected 394 individuals, aged 62.4 ± 11.8 years, from the Corinthia study which was conducted in the homonym region in Greece. Half of the participants lived in a high air pollution area (HAPA) and the other half in a low air pollution area (LAPA) for at least 10 years. LTL was measured from whole blood by Southern blot and carotid-femoral pulse wave velocity (cfPWV), carotid intima media thickness (cIMT) and presence of carotid plaque were determined to evaluate cardiovascular health. Results: We found no difference in age and sex adjusted LTL between HAPA and LAPA groups (p=0.42). Using the median LTL (6.78 kb) as a cutoff, the cohort was divided into four groups, Group 1 (LAPA/long LTL): 100 patients, Group 2 (LAPA/short LTL): 92 patients, Group 3 (HAPA/ long LTL): 98 patients and Group 4 (HAPA/short LTL): 104 patients. Patients from Group 4 displayed higher cfPWV and cIMT than the patients from the 3 other groups (p<0.05). These differences subsisted after adjustment for age and sex. Carotid plaque prevalence increased from 15% for Group 1 to 18% for Group2, 27% for Group 3 and 39% for Group 4 (p < 0.01). Conclusions: In this cross-sectional study, prolonged exposure to high air pollution displays no direct effect on telomere dynamics. Interestingly, longer telomere length may at least partially protect from negative effects of high air pollution exposure on vascular health. These results could be used for personalized cardiovascular risk prevention.