Additional Impact of Glucose Tolerance on Telomere Length in Persons With and Without Metabolic Syndrome in the Elderly Ukraine Population

Rationale: Association between different components of metabolic syndrome and the rate of age-related telomere shortening was reported repeatedly, although some findings are inconsistent across studies, suggesting the need for further research on the topic. In the present study, we examined relationships between different components of metabolic syndrome (MetS); glucose tolerance reflected in 2-h post-load plasma glucose (2hPG) levels and age on the leukocyte telomere length (LTL) in Ukraine population. Methods: The study was conducted on the 115 adult individuals residing in the Kyiv region (Ukraine). Among them, 79 were diagnosed with MetS according to the International Diabetes Federation definition. LTL were determined by a qPCR-based method. Multivariate logistic regression (MLR) and artificial neural networks (ANN) modeling were used for the analysis of the results. ROC-analysis was also performed to compare the predictively values of this models. Results: MetS was associated with a high (OR = 3.0 CI 1.3-6.7; p = 0.01) risk of having shorter telomeres that remained significant after adjusting for age, gender and 2hPG levels. Fasting plasma glucose (FPG) levels and other MetS components did not affect the magnitude of the relationship and did not reveal the independent influence of these factors. The level of 2hPG in turn, demonstrated a significant relationship (OR = 1.3 CI 1.0-1.6 per 1 mmol/l; p = 0.04) with LTL regardless of the presence of MetS. The non-linearity of the interactions between age, gender and 2hPG level was revealed by neural network modeling (AUC = 0.76 CI 0.68-0.84). Conclusion: Our study found that impaired glucose tolerance, but not FPG levels, affected the association between LTL and MetS, which may be also indicative for pathophysiological differences in these hyperglycemia categories. 2hPG levels can provide an opportunity for a more accurate diagnostics of MetS and for evaluating the rate of aging in patients with MetS. Further research, however, is needed to verify this assumption.

Hyperglycemia attenuates the association between telomere length and age in Ukrainian population

Diabetes-related conditions such as chronic hyperglycemia and related oxidative stress and inflammation were repeatedly associated with accelerated telomere shortening in epidemiological studies, although some findings are inconsistent. In present study, we aimed to assess the impact of disturbances in glucose metabolism on association between age and leukocyte telomere length (LTL) in the Ukrainian population. The study was conducted on the 119 adult subjects aged between 43 and 87 years residing in the Kyiv region, Ukraine. LTL was determined by a quantitative PCR-based method. LTL was negatively correlated with the measure of abdominal obesity such as waist-hip ratio, as well as with both fasting plasma glucose (FPG) and two-hour post-load glucose (2hPG) levels. Consistently with previous studies, a significant negative association between LTL and age was observed in individuals with normal (<5.6 mmol/L) FPG levels. Unexpectedly, however, no association was found in subjects with impaired glucose metabolism assessed by abnormal FPG or/and 2hPG levels. No association between LTL and age was observed in a logistic regression model; the association between LTL and age became significant after adjusting for FPG level. In the FPG-adjusted model, 1.6-time lower odds to have long telomere length were indicated for each 10 years increase in age. We hypothesize that the attenuation of association between LTL and age in hyperglycemic persons can likely be attributed to the interaction of multidirectional processes determining this relationship.