Telomere shortening in somatic tissues largely reflects stem cell replication. Previous human studies of telomere attrition were predominantly conducted on leukocytes. However, findings in leukocytes cannot be generalized to other tissues. Here we measure telomere length in leukocytes, skeletal muscle, skin and subcutaneous fat of 87 adults (aged 19–77 years). Telomeres are longest in muscle and shortest in leukocytes, yet are strongly correlated between tissues. Notably, the rates of telomere shortening are similar in the four tissues. We infer from these findings that differences in telomere length between proliferative (blood and skin) and minimally proliferative tissues (muscle and fat) are established during early life, and that in adulthood, stem cells of the four tissues replicate at a similar rate.

Chronological age is the primary determinant of stiffness of central arteries. Increased stiffness is an independent indicator of cardiovascular risk. The aim of this study was to determine whether telomere length, a possible index of biological aging, provides a better account than chronological age for variation in arterial stiffness, evaluated by measuring pulse pressure and aortic pulse wave velocity. The study population included 193 French subjects (120 men, 73 women), with a mean age of 56±11 years, who were not on any antihypertensive medications. Telomere length was evaluated in white blood cells by measuring the mean length of the terminal restriction fragments. Age-adjusted telomere length was longer in women than in men (8.67±0.09 versus 8.37±0.07 kb; P =0.016). In both genders, telomere length was inversely correlated with age ( P <0.01). Multivariate analysis showed that in men, but not in women, telomere length significantly contributed to pulse pressure and pulse wave velocity variations. In conclusion, telomere length provides an additional account to chronological age of variations in both pulse pressure and pulse wave velocity among men, such that men with shorter telomere length are more likely to exhibit high pulse pressure and pulse wave velocity, which are indices of large artery stiffness. The longer telomere length in women suggests that for a given chronological age, biological aging of men is more advanced than that of women.

Background — Elastic artery stiffness, a result of arterial aging, is an independent indicator of cardiovascular risk. The aim of the present longitudinal study was to compare the progression of aortic stiffness over a 6-year period in treated hypertensive subjects and normotensive subjects, and to evaluate the determinants of this progression. Methods and Results — Data for the present analysis were gathered from 483 subjects who had 2 health checkups at the Centre d’Investigations Préventives et Cliniques, the first one in 1992–1993 and the second one in 1998–1999. Carotid-femoral pulse wave velocity (PWV) was used to evaluate aortic stiffness in 187 hypertensive subjects who were under treatment at the time of the first visit and throughout the follow-up period, and in 296 subjects who were classified as normotensive during the first visit and who remained treatment-free throughout the follow-up period. In both populations, PWV progression was higher in older subjects. Annual rates of progression in PWV in treated hypertensives were significantly higher than in normotensives. Only treated hypertensives with well-controlled blood pressure levels at the time of both visits had a PWV progression similar to that of normotensives. In treated hypertensives, high heart rate and high creatinine during the first visit were associated with an accelerated progression in PWV. Conclusions — The presence of high blood pressure, high heart rate, and high serum creatinine were the major determinants of accelerated progression of aortic stiffness in treated hypertensives. This is the first longitudinal study to evaluate the determinants of arterial aging over an extended period of time.

To validate a new, small portable tonometer (PulsePen) that is able to assess carotid artery pressure and to measure pulse wave velocity (PWV) non-invasively. Its software provides absolute arterial pressure values, an assessment of arterial pulse wave contours, an estimation of reflection waves and measurements of PWV. Two validation studies were carried out. The aim of the first study was to compare arterial pressure values and pulse wave contours recorded in the carotid artery using the PulsePen versus intra-arterial simultaneous measurements in 10 patients undergoing cardiac catheterization. The pulse wave contour was assessed using Fourier analysis. The comparison between the two methods showed no difference in arterial pressure wave spectral moduli from harmonics 1 to 6. The second study compared PWV measurements taken with the PulsePen (one tonometer) and measurements performed with two Millar tonometers in 68 subjects (32 men, 36 women). PulsePen measurements were realized as two consecutive measurements in the carotid and femoral arteries, both synchronized by electrocardiogram. The pulse wave transit time was calculated as the difference between the time delay of the femoral pulse wave and the carotid pulse wave in relation to the R wave of the electrocardiogram. These measurements were compared with PWV obtained by simultaneous carotid and femoral measurements with the two Millar tonometers. No difference between the two methods was found, with a variation coefficient of 7.7%. The variation coefficients of the inter-observer and intra-observer reproducibility for the PulsePen were 7.9 and 7.2%, respectively. These results show that the PulsePen enables an easy and reliable evaluation of central arterial pressure and stiffness in clinical ambulatory practice, especially in high-risk patients in whom arterial stiffness has been shown to be a significant indicator of morbidity and mortality.

Recent studies have shown that individuals with shorter telomeres present a higher prevalence of arterial lesions and higher risk of cardiovascular disease mortality. As a group, patients with high blood pressure are at an increased risk for cardiovascular diseases. However, some hypertensive patients are more prone than others to atherosclerotic lesions. The main objective of this study was to examine the relationship between telomere length, as expressed in white blood cells, and carotid artery atherosclerotic plaques in hypertensive males. Data from 163 treated hypertensive men who were volunteers for a free medical examination were analyzed. Extracranial carotid plaques were assessed with B-mode ultrasound. Telomere length was measured from DNA samples extracted from white blood cells. The results of this study show that telomere length was shorter in hypertensive men with carotid artery plaques versus hypertensive men without plaques (8.17±0.07 kb versus 8.46±0.07 kb; P <0.01). Multivariate analysis showed that in addition to age, telomere length was a significant predictor of the presence of carotid artery plaques. The findings from this study suggest that in the presence of chronic hypertension, which is a major risk factor for atherosclerotic lesions, shorter telomere length in white blood cells is associated with an increased predilection to carotid artery atherosclerosis.

Research from JAMA Internal Medicine — Treatment With Multiple Blood Pressure Medications, Achieved Blood Pressure, and Mortality in Older Nursing Home Residents — The PARTAGE Study