Functional haplotypes of the hTERT gene, leukocyte telomere length shortening, and the risk of peripheral arterial disease

The causal relationship between genetically determined telomere length and meningiomas risk

Background

Studies have shown that longer leukocyte telomere length (LTL) is significantly associated with increased risk of meningioma. However, there is limited evidence concerning the causal association of LTL with benign and malignant meningiomas or with the location of benign tumors.

Methods

We used three LTL datasets from different sources, designated by name and sample size as LTL-78592, LTL-9190, and LTL-472174. The linkage disequilibrium score (LDSC) was used to explore the association between LTL and meningioma. We utilized two-sample bidirectional Mendelian randomization (TSMR) to evaluate whether LTL is causally related to meningioma risk. We adjusted for confounders by conducting multivariable Mendelian randomization (MVMR).

Results

In the LTL-78592, longer LTL was significantly associated with increased risk of malignant [odds ratio (OR) = 5.14, p = 1.04 × 10-5], benign (OR = 4.81, p < 0.05), benign cerebral (OR = 5.36, p < 0.05), and benign unspecified meningioma (OR = 8.26, p < 0.05). The same results were obtained for the LTL-9190. In the LTL-472174, longer LTL was significantly associated with increased risk of malignant (OR = 4.94, p < 0.05), benign (OR = 3.14, p < 0.05), and benign cerebral meningioma (OR = 3.59, p < 0.05). Similar results were obtained in the MVMR. In contrast, only benign cerebral meningioma displayed a possible association with longer LTL (OR = 1.01, p < 0.05). No heterogeneity or horizontal pleiotropy was detected.

Conclusion

In brief, genetically predicted longer LTL may increase the risk of benign, malignant, and benign cerebral meningiomas, regardless of the LTL measure, in European populations.

Association study of leukocyte telomere length and genetic polymorphism within hTERT promoter with type 2 diabetes in Bangladeshi population

Telomeres are protective cap on the ends of DNA of non-coding tandem repeats of TTAGGG. Human telomerase reverse transcriptase (hTERT) is a catalytic subunit of telomerase that maintains the structure of telomeres. Type 2 diabetes (T2D) affects multi-organ and telomere length by altering telomerase activity. We aimed to evaluate the relative telomere length (RTL) and risk association of rs2853669 with T2D in Bangladeshi population. RTL was measured in 408 unrelated Bangladeshi (224 T2D and 184 healthy) using primers for target gene and reference gene albumin. Genotypic frequencies for rs2853669 were determined using TaqMan® probes. The mean level of age adjusted RTL (AARTL) varied significantly between the healthy and individuals with T2D for all the genotypes with respect to rs2853669. Moreover, healthy individuals had significantly higher AARTL than T2D. Similar findings were observed when study participants were stratified based on their gender. Association studies revealed that under codominant model of inheritance, TC genotype showed protective role against development of type 2 diabetes. This study suggests a possible role of telomere biology in T2DM, but their association needs to be evaluated further with a larger series and matched healthy controls.

Leukocyte Telomere Length, DNA Oxidation, and Risk of Lower-Extremity Amputation in Patients With Long-standing Type 1 Diabetes

OBJECTIVE

Telomere shortening and DNA oxidation are associated with premature vascular aging, which may be involved in lower-extremity amputation (LEA). We sought to investigate whether leukocyte telomere length (LTL) and plasma 8-hydroxy-2'-deoxyguanosine (8-OHdG), a biomarker of DNA oxidation, were associated with LEA in subjects with type 1 diabetes at high vascular risk.

RESEARCH DESIGN AND METHODS

LTL (quantitative PCR) and plasma 8-OHdG concentrations (immunoassay method) were assessed at baseline in the GENEDIAB (Génétique de la Néphropathie Diabétique) type 1 diabetes cohort. Logistic and Cox proportional hazards regression models were fitted to estimate odds ratio (OR) (at baseline) and hazard ratio (HR) (during follow-up), with related 95% CI, by increasing biomarker tertiles (T1, T2, T3).

RESULTS

Among 478 participants (56% male, mean ± SD age 45 ± 12 years and diabetes duration 29 ± 10 years), 84 patients had LEA at baseline. Baseline history of LEA was associated with shorter LTL (OR for T2 vs. T1 0.62 [95% CI 0.32-1.22] and for T3 vs. T1 0.41 [0.20-0.84]) but not with plasma 8-OHdG (1.16 [0.56-2.39] and 1.24 [0.61-2.55], respectively). New cases of LEA occurred in 34 (12.3%) participants during the 10-year follow-up. LTL were shorter (HR T2 vs. T1 0.25 [95% CI 0.08-0.67] and T3 vs. T1 0.29 [0.10-0.77]) and plasma 8-OHdG higher (2.20 [0.76-7.35] and 3.11 [1.07-10.32]) in participants who developed LEA during follow-up compared with others. No significant interaction was observed between biomarkers on their association with LEA.

CONCLUSIONS

We report the first independent association between LTL shortening and excess risk of LEA in type 1 diabetes. High plasma 8-OHdG was also associated with incident LEA but partly dependent on cofounding variables.

Correlation of human telomerase reverse transcriptase single nucleotide polymorphisms with in vitro fertilisation outcomes

PURPOSE

To explore whether it is possible to predict the number and quality of the embryo using a few particular hTERT SNPs.

METHODS

We included 997 Han Chinese women who were genetically unrelated and underwent assisted reproduction using IVF from September 2014 to December 2015. DNA was genotyped by using TaqMan real-time quantitative PCR.

RESULTS

Among the 997 patients, individuals with the CC genotype of rs2075786 had a significantly lower number of good-quality embryos than those with the TT+TC genotypes. Compared with the CT+CC genotype carriers, patients carrying the TT genotype of rs2853677 had a significantly lower number of oocytes retrieved, mature oocytes and available embryos. Among the 750 patients aged ≤ 35 years, individuals with the AA+AG genotypes of rs2853691 had a significantly higher number of good-quality embryos than those with the GG genotype. The haplotype analysis showed that the TTTG (rs2853672/rs2853669/rs2735940/rs2736108) haplotype was more likely to lead to more than three good-quality embryos in patients aged ≤ 35 years.

CONCLUSIONS

Our study suggests that the hTERT SNP is associated with IVF outcomes.

Inherited Genetic Variants Associated with Melanoma BRAF/NRAS Subtypes

BRAF and NRAS mutations arise early in melanoma development, but their associations with low-penetrance melanoma susceptibility loci remain unknown. In the Genes, Environment and Melanoma Study, 1,223 European-origin participants had their incident invasive primary melanomas screened for BRAF/NRAS mutations and germline DNA genotyped for 47 single-nucleotide polymorphisms identified as low-penetrant melanoma-risk variants. We used multinomial logistic regression to simultaneously examine each single-nucleotide polymorphism's relationship to BRAF V600E, BRAF V600K, BRAF other, and NRAS+ relative to BRAF-/NRAS- melanoma adjusted for study features. IRF4 rs12203592*T was associated with BRAF V600E (odds ratio [OR] = 0.59, 95% confidence interval [CI] = 0.43-0.79) and V600K (OR = 0.65, 95% CI = 0.41-1.03), but not BRAF other or NRAS+ melanoma. A global test of etiologic heterogeneity (Pglobal = 0.001) passed false discovery (Pglobal = 0.0026). PLA2G6 rs132985*T was associated with BRAF V600E (OR = 1.32, 95% CI = 1.05-1.67) and BRAF other (OR = 1.82, 95% CI = 1.11-2.98), but not BRAF V600K or NRAS+ melanoma. The test for etiologic heterogeneity (Pglobal) was 0.005. The IRF4 rs12203592 associations were slightly attenuated after adjustment for melanoma-risk phenotypes. The PLA2G6 rs132985 associations were independent of phenotypes. IRF4 and PLA2G6 inherited genotypes may influence melanoma BRAF/NRAS subtype development.

Activating the PGC-1α/TERT Pathway by Catalpol Ameliorates Atherosclerosis via Modulating ROS Production, DNA Damage, and Telomere Function: Implications on Mitochondria and Telomere Link

Catalpol, an iridoid glucoside, has been found present in large quantities in the root of Rehmannia glutinosa L. and showed a strong antioxidant capacity in the previous study. In the present work, the protective effect of catalpol against AS via inhibiting oxidative stress, DNA damage, and telomere shortening was found in LDLr^-/- mice. This study also shows that activation of the peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α)/telomerase reverse transcriptase (TERT) pathway, which is the new link between mitochondria and telomere, was involved in the protective effects of catalpol. Further, by using PGC-1α or TERT siRNA in oxLDL-treated macrophages, it is proved that catalpol reduced oxidative stress, telomere function, and related DNA damage at least partly through activating the PGC-1α/TERT pathway. Moreover, dual luciferase activity assay-validated catalpol directly enhanced PGC-1α promoter activity. In conclusion, our study revealed that the PGC-1α/TERT pathway might be a possible therapeutic target in AS and catalpol has highly favorable characteristics for the treatment of AS via modulating this pathway.

Maternal human telomerase reverse transcriptase variants are associated with preterm labor and preterm premature rupture of membranes

Objective

Premature aging and short telomere lengths of fetal tissues are associated with spontaneous preterm labor (PTL) and preterm premature rupture of membranes (pPROM). Maintenance of telomere length is performed by the enzyme telomerase. Human telomerase reverse transcriptase (hTERT) is a subunit of telomerase, and its dysfunction affects telomere shortening. This study assessed whether maternal or fetal genetic variations in the hTERT gene are associated with PTL or pPROM.

Methods

A case (PTL or pPROM) control (term birth) genetic association study was conducted in 654 non-Hispanic white mothers (438 term, 162 PTL, 54 pPROM) and 502 non-Hispanic white newborns (346 term, 116 PTB, 40 pPROM). Maternal and fetal DNA samples were genotyped for 23 single nucleotide polymorphisms (SNPs) within the hTERT gene. Allele frequencies were compared between cases and controls, stratified by PTL and pPROM. Maternal and fetal data were analyzed separately.

Results

Allelic differences in one SNP of hTERT (rs2853690) were significantly associated with both PTL (adjusted OR 2.24, 95%CI 1.64–3.06, p = 2.32e-05) and with pPROM (adjusted OR 7.54, 95%CI 3.96–14.33, p = 2.39e-07) in maternal DNA. There was no significant association between the hTERT SNPs analyzed and PTL or pPROM in the fetal samples.

Conclusion

hTERT polymorphisms in fetal DNA do not associate with PTL or pPROM risk; however, maternal genetic variations in hTERT may play a contributory role in risk of PTL and PPROM.

Leukocyte telomere length and cardiovascular disease in African Americans: The Jackson Heart Study

BACKGROUND AND AIMS

In European descent populations, shorter leukocyte telomere length (LTL) has been associated with subclinical atherosclerosis, cardiovascular disease (CVD), and mortality, while longer LTL has been associated with greater left ventricular hypertrophy. We evaluated the relationship of LTL with subclinical cardiovascular disease indices and incident clinical events and mortality in African Americans (AAs).

METHODS

Analyses were restricted to 2518 participants of the Jackson Heart Study (JHS) with LTL measured by Southern blot in baseline blood samples.

RESULTS

Adjusting for established CVD risk factors, longer LTL was significantly associated with lower prevalence of coronary artery calcification (CAC) (odds ratio (OR) = 0.810) per 1 kb increase in LTL; (95% confidence interval [CI] 0.656, 0.9998), p=0.0498). Longer LTL was also associated with higher ankle brachial index (ABI) (β = 0.023; (95% CI 0.004, 0.042), p=0.017) when comparing the highest to the lowest LTL quartile. There were no significant associations between LTL and abdominal aortic calcification, carotid intima-media thickness, or left ventricular mass. After a median follow-up of 9 years, longer LTL was associated with lower risk of incident ischemic stroke (hazard ratio (HR) 0.69 (95% CI 0.48, 0.99), p=0.044) and total mortality (HR 0.81 (95% CI 0.67, 0.97), p=0.026) in age and sex adjusted models, but these associations were no longer significant in fully adjusted models.

CONCLUSIONS

Among a community-based cohort of AAs, longer LTL was nominally associated with lower odds of CAC and increased ABI, indicative of decreased prevalence of subclinical atherosclerosis and peripheral arterial disease. These findings do not offer strong support for LTL as an independent biomarker of CVD risk in AAs.

Joint Assessment of Donor and Recipient hTERT Gene Polymorphism Provides Additional Information for Early Kidney Transplantation Outcomes

Background

There are several genes and genetic loci affecting telomere length, including hTERT gene and BICD1 gene as well as polymorphisms within chromosome 18. It has been demonstrated that the age of the donor is a negative factor associated with long-term kidney allograft function, and that post-transplant complications accelerate transplanted organ aging, thus contributing to estimated glomerular filtration rate (eGFR) decreases. The aim of this study was a joint assessment of donors’ and recipients’ hTERT and BICD1 genes as well as chromosome 18 polymorphisms with regard to early kidney transplantation outcomes.

Material/Methods

The study enrolled 74 pairs of Polish Caucasian kidney allograft cadaveric donors (60% male, mean age 45.99±14.62) and recipients (50.0% male, mean age 48.89±13.50). The transplantation procedure (Tx) was performed between 2001 and 2012. All samples were genotyped in duplicate using Real-Time PCR.

Results

This study showed that rs2735940 hTERT CX-TT donor-recipient genotype pair was associated with almost five times higher odds (OR=4.82; 95% CI: 1.32–18; p=0.016) of delayed graft function (DGF), and that rs2735940 hTERT, rs2630578 BICD1, and rs7235755 chromosome 18 polymorphisms combined pairs were not associated with acute rejection (AR).

Conclusions

In conclusion, both the donor’s and the recipient’s rs2735940 hTERT gene polymorphism was associated with early graft function after transplantation. The odds of DGF were almost five times higher for a combination of CX (CT or CC) donor genotype and TT recipient genotype. Joint assessment of donor-recipient genotype pairs provides more information for prediction of early kidney transplantation outcomes.

Telomere Length Assessment for Prediction of Organ Transplantation Outcome. Future or Failure: A Review of the Literature

Telomeres are located at each end of eukaryotic chromosomes. Their functional role is genomic stability maintenance. The protective role of telomeres depends on various factors, including number of nucleotides repeats, telomere-binding proteins, and telomerase activity. Organ transplantation is the preferred replacement therapy in the case of chronic kidney disease and the only possibility of sustaining recipients’ life in the case of advanced liver failure. While the prevalence of acute rejection is constantly decreasing, prevention of transplanted organ long-term function loss is still challenging. It has been demonstrated that post-transplant stressors accelerate aging of the allografts manifested through telomere shortening.

The aim of this paper was to evaluate the importance of telomere length assessment for prediction of organ transplantation outcome. Literature review included the 10 most important studies regarding linkage between allograft function and telomere erosion, including 2 of our own reports.

Telomere length assessment is useful to predict organ transplantation outcome. The importance of telomere length as a prediction marker depends on the analyzed material. To obtain reliable results, both graft cells (donor material) and lymphocytes (recipient material) should be examined. In the case of kidney transplantation, assessment of telomere length in the early post-transplant period allows prediction of the long-term function of the transplanted organ. To increase the accuracy of transplantation outcome prediction, telomere length assessment should be combined with evaluation of other aging biomarkers, like CDKN2A (p16). Large-scale clinical studies regarding telomere length measurement, including genome wide association analysis introducing relevant genetic factors, are needed for the future.

Telomere mean length in patients with diabetic retinopathy

Telomere regression has been shown to be associated with several complex disorders like diabetes mellitus, cancer, cataract etc. Diabetic retinopathy develops as a complication of chronic hyperglycemia leading to increased oxidative stress that may potentially lead to shortening of telomeres. We sought to determine whether there is any association between telomere mean length (TML) of peripheral blood monocytes with the presence and severity of diabetic retinopathy. The study involved 120 subjects, comprising 27 non-insulin dependent diabetes mellitus (NIDDM) without any diabetic retinopathy (NDR), 45 NIDDM subjects with non-proliferative diabetic retinopathy (NPDR), 12 NIDDM subjects with proliferative diabetic retinopathy (PDR) and 36 healthy controls. Determination of TML of the study subjects was performed by Southern hybridization using telomere probe. Among the biochemical parameters, HBA1c showed a negative correlation with shortened telomeres in the PDR subjects. However, telomere length was positively correlated with high density lipo protein (HDL) in the control subjects. The control group had significantly greater TML as compared to the rest of the groups and the NDR subjects with NPDR and PDR had substantially decreased TML than the NIDDM subjects without retinopathy.

Telomerase Reverse Transcriptase (TERT) Gene Variations and Susceptibility of Colorectal Cancer

AIM

Colorectal cancer is the third most common cause of cancer-related mortality. Previous studies demonstrated increased telomerase activity in colorectal cancer tissue and suggested a prognostic value for patients with colorectal carcinoma. Telomerase reverse transcriptase (TERT), one of the main functional subunits of the telomerase, is an important factor in modulating telomerase activity, telomere length, and genomic stability. However, there are few studies that have addressed the association between genetic variation at TERT and the risk of colorectal cancer.

METHOD

We evaluated the influence of three common single-nucleotide polymorphisms (SNPs) of the TERT gene (rs2853669, rs2736100, rs2736098) on susceptibility to colorectal cancer in 104 patients and 135 controls in a Turkish population.

RESULTS

We observed that rs2736098 was significantly associated with increased risk of colorectal cancer (OR = 2.53; 95% CI = 1.26-5.10; p = 0.008). On the other hand, rs2736100 and rs2853669 showed no association with colorectal cancer (p ≥ 0.128).

CONCLUSION

These findings are the first results of TERT allele distributions in the Turkish population and also provide increased understanding with respect to colorectal cancer etiology.

Inherited genetic variants associated with occurrence of multiple primary melanoma

Recent studies, including genome-wide association studies, have identified several putative low-penetrance susceptibility loci for melanoma. We sought to determine their generalizability to genetic predisposition for multiple primary melanoma in the international population-based Genes, Environment, and Melanoma (GEM) Study. GEM is a case-control study of 1,206 incident cases of multiple primary melanoma and 2,469 incident first primary melanoma participants as the control group. We investigated the odds of developing multiple primary melanoma for 47 SNPs from 21 distinct genetic regions previously reported to be associated with melanoma. ORs and 95% confidence intervals were determined using logistic regression models adjusted for baseline features (age, sex, age by sex interaction, and study center). We investigated univariable models and built multivariable models to assess independent effects of SNPs. Eleven SNPs in 6 gene neighborhoods (TERT/CLPTM1L, TYRP1, MTAP, TYR, NCOA6, and MX2) and a PARP1 haplotype were associated with multiple primary melanoma. In a multivariable model that included only the most statistically significant findings from univariable modeling and adjusted for pigmentary phenotype, back nevi, and baseline features, we found TERT/CLPTM1L rs401681 (P = 0.004), TYRP1 rs2733832 (P = 0.006), MTAP rs1335510 (P = 0.0005), TYR rs10830253 (P = 0.003), and MX2 rs45430 (P = 0.008) to be significantly associated with multiple primary melanoma, while NCOA6 rs4911442 approached significance (P = 0.06). The GEM Study provides additional evidence for the relevance of these genetic regions to melanoma risk and estimates the magnitude of the observed genetic effect on development of subsequent primary melanoma.

Telomere reverse transcriptase (TERT) rs2735940 increases cancer risk

Background

Telomerase reverse transcriptase (TERT) rs2735940 polymorphism was found to be associated with increased cancer risk. However, recent studies reported controversial results. The aim of our study was to detect its relationship with cancer risk.

Material/Methods

EMBASE and PubMed databases were searched for all publications until October 2014. ORs and 95% CIs were applied to investigate the association in the random-effects model.

Results

Thirteen case-control studies with 19385 cases and 17558 controls were included in this study. We found a significant association between cancer risk and TERT rs2735940 polymorphism (OR=1.06, 95% CI 1.02–1.11, P=0.005). In the subgroup analysis by ethnicity, a marginal association was found in Caucasians (OR=1.05, 95% CI 1.00–1.10, P=0.05), but not in Asians (OR=1.01, 95% CI 0.82–1.24, P=0.93). In the subgroup analysis by cancer site, this polymorphism was significantly associated with lung cancer risk (OR=1.08, 95% CI 1.02–1.13, P=0.004).

Conclusions

TERT rs2735940 polymorphism was significantly associated with cancer risk, especially lung cancer.

Telomerase Gene (hTERT) and Survival: Results From Two Swedish Cohorts of Older Adults

Telomere length has been associated with longevity. As telomere length is partly determined by the human telomerase reverse transcriptase (hTERT), we investigated the association between an hTERT polymorphism located in its promoter region (⁻¹³²⁷T/C) and longevity in two cohorts of older adults. Participants from the Kungsholmen project (KP; n = 1,205) and the Swedish National study of Aging and Care in Kungsholmen (SNAC-K; n = 2,764) were followed for an average period of 7.5 years. The main outcomes were hazard ratios (HR) of mortality and median age at death. In both cohorts, mortality was lower in female T/T carriers, aged 75+ years in KP (HR = 0.8, 95% CI: 0.5–0.9) and 78+ years in SNAC-K (HR = 0.6, 95% CI: 0.4–0.8) compared with female C/C carriers. T/T carriers died 1.8–3 years later than the C/C carriers. This effect was not present in men, neither in SNAC-K women aged 60–72 years. The association was not modified by presence of cancer, cardiovascular diseases, number of chronic diseases, or markers of inflammation, and did not interact with APOE genotype or estrogen replacement therapy. The gender-specific increased survival in T/T carriers can be due to a synergistic effect between genetic background and the life-long exposure to endogenous estrogen.

TERT polymorphisms rs2853669 and rs7726159 influence on prostate cancer risk in Russian population

Telomere length and telomerase activity have been hypothesized to play a role in cancer development. The aim of our study was to investigate the association of allelic variants of three functional polymorphisms rs2853669, rs2736100, and rs7726159 in the telomerase reverse transcriptase (TERT) gene with the risk of the breast cancer and prostate cancer in Russian population. Six hundred sixty women with breast cancer, 372 men with prostate cancer, and corresponding control groups of 523 women and 363 men were included in the present case-control study. We observed an association of allele rs2853669 C with increased risk of prostate cancer (co-dominant model TC vs. TT OR = 1.65, P = 0.002; additive model OR = 1.42, P = 0.005; dominant model: OR = 1.64, P = 0.001) and allele rs7726159 A with reduced risk of this malignancy (сo-dominant model: AA vs. CC OR = 0.42, P = 0.002; additive model: OR = 0.69, P = 0.002; dominant model: OR = 0.67, P = 0.01; recessive model: OR = 0.48, P = 0.005). None of the studied polymorphisms showed an association with the risk of breast cancer. Our results provide evidence that the TERT gene variability modulate prostate cancer predisposition in ethnical Russians.

Telomeres in molecular epidemiology studies

Telomeres are long nucleotide repeats and protein complexes at the ends of chromosomes that are essential for maintaining chromosomal stability. They shorten with each cell division, and therefore, telomere length is a marker for cellular aging and senescence. Epidemiological research of telomeres investigates the role that these genetic structures have in disease risk and mortality in human populations. This chapter provides an overview of the current telomere epidemiology research and discusses approaches taken in these investigations. We also highlight important methodological considerations that may affect data interpretation.

Association between telomere length and type 2 diabetes mellitus: a meta-analysis

Background

Several epidemiological studies have examined the association between shortened telomere length and type 2 diabetes mellitus (T2DM), while the results remained conflicting. We conducted a meta-analysis to derive a more precise estimation of the relationship between them.

Methods

We systematically reviewed the databases of PubMed, EMBASE, and Web of Science for all studies on the association between telomere length and T2DM. We conducted this study assessed by STATA 11.0. Data were summarized using random-effects or fixed-effects meta-analysis. The heterogeneity and publication bias among studies were examined by using χ²-based Q statistic test and Egger’s test, respectively.

Results

Nine cohorts consisting of 5759 cases and 6518 controls were selected into the meta-analysis. The results indicated that shortened telomere length was significantly associated with T2DM risk (OR: 1.291; 95% CI: 1.112, 1.498; P<0.001) with heterogeneity (I² = 71.6%). When three cohorts responsible for the heterogeneity were excluded, the pooled OR for the remaining cohorts indicated a significant association between shortened telomere length and T2DM (OR: 1.117; 95% CI: 1.002, 1.246; P = 0.045) without heterogeneity.

Conclusion

We found a statistically significant association between shortened telomere length and T2DM.

The association of relative telomere length with symptomatic peripheral arterial disease: results from the CAVASIC study

BACKGROUND AND OBJECTIVES

Short telomere length has been described to be associated with biological aging including atherosclerosis phenotypes. However, information in patients with symptomatic peripheral arterial disease (PAD) is sparse. We therefore aimed to investigate whether inter-individual differences in relative telomere length (RTL) are associated with symptomatic PAD.

DESIGN

We measured RTL by a quantitative PCR method in the CAVASIC Study, a cohort of 241 male Caucasian patients diagnosed with intermittent claudication and 249 age- and diabetes-matched controls.

RESULTS

We observed significantly shorter mean RTL in patients than in controls (1.24 ± 0.19 vs. 1.32 ± 0.23, p < 0.001). Each shortening of RTL by one standard deviation significantly increased the odds for PAD by 44%: age-adjusted OR = 1.44 (95%CI 1.19-1.75, p < 0.001). This association remained significant after additional adjustment for log-C-reactive protein, glomerular filtration rate, HDL cholesterol, current smoking and log N-terminal pro-B-type natriuretic peptide (NT-proBNP). Excluding patients with prevalent cardiovascular disease revealed very similar results. When we compared the model fit of the various adjustment models including cardiac risk factors and/or NT-proBNP the addition of RTL significantly improved discrimination between patients and controls.

CONCLUSION

This study in a male cohort of patients with intermittent claudication and age- and diabetes-matched controls indicates a significant association of shorter relative telomere length with PAD. Our results reinforce RTL as a marker for PAD that reflects the influence of genetic and environmental risk factors. Moreover, the association remains significant after excluding patients and controls free from prevalent cardiovascular disease.