Increased aortic stiffness is persistent in type 1 diabetic women: a follow-up study.

AIMS/HYPOTHESIS: We have previously reported that women, not men, with type 1 diabetes have increased aortic stiffness. Increased arterial stiffness may explain why diabetic women have a particularly high risk of developing cardiovascular complications. We have now followed up our previously investigated patients after 7 years, with a view to evaluating whether the sex difference was persistent, and also evaluating the degree of progression with time and the relationship between stiffness versus intima media thickness of the aorta. METHODS: Stiffness (beta) of the abdominal aorta (echo-tracking sonography) and intima media thickness (B-mode ultrasound) were assessed in 23 women and 19 men with type 1 diabetes and compared with matched healthy individuals. RESULTS: At follow-up, aortic stiffness was still higher (60%) (p=0.0016) in diabetic than in control women, whereas there was no similar difference (p=0.4) between diabetic and control men. No progression of stiffness had occurred over the 7 years. At follow-up, the intima media thickness was increased and the internal diameter of the aorta was decreased in diabetic men and women without any sex-related difference. CONCLUSIONS/INTERPRETATION: The increased aortic stiffness that affects type 1 diabetic patients seems to be an early event that soon reaches a plateau without any further increase. Increased aortic stiffness in type 1 diabetic women seems to be a sex-specific functional disorder unrelated to the degree of underlying atherosclerosis.

Dynamic behaviour of the common femoral artery: age and gender of minor importance.

The distensibility of elastic arteries has been extensively studied, while studies of muscular arteries are sparse. The influences of age and gender on the mechanical properties of the common femoral artery (CFA) were studied. The pulsatile diameter changes of the CFA were noninvasively measured using echo-tracking sonography in 173 healthy volunteers (95 females, 78 males, range 7-81 years). In combination with blood pressure measurements, stiffness (beta) and pressure strain elastic modulus (Ep) were calculated. Neither beta nor Ep was related to age or gender and a considerable interindividual variation was present. The CFA diameter increased with age. In conclusion, the distensibility of this muscular artery is not clearly affected by age or gender, although the diameter increases with age. This indicates remodelling of the arterial wall and an impact of vascular smooth muscles on long-term wall mechanics. Thus, there appear to be fundamental differences in the dynamic behaviour of the common femoral artery when compared to elastic arteries, such as the aorta and the common carotid artery.

Increased aortic stiffness in women with type 1 diabetes mellitus is associated with diabetes duration and autonomic nerve function.

AIMS: The increase in risk for cardiovascular complications in diabetic women is even greater than that in diabetic men. We found arterial stiffness to be increased in women, but not in men, with Type 1 diabetes mellitus (DM). The aims of the present study were to evaluate whether the changes in arterial distensibility are influenced by diabetes duration and to evaluate any association between autonomic neuropathy and decreased arterial distensibility. METHODS: Stiffness of the abdominal aorta was measured noninvasively using echo-tracking sonography and parasympathetic function by heart rate variation during deep breathing (E/I ratio) in 40 women (mean age 33 years, range 20-61) and 38 men (mean age 36 years, range 22-56) with Type 1 DM. RESULTS: There was a significant correlation between aortic stiffness and duration of diabetes in women (r = 0.41, P = 0.008), but not in men (r = 0.15, P = 0.35). There was also a significant correlation between aortic stiffness and the E/I ratio in women (r = -0.49, P = 0.002), but not in men (r = -0.14, P = 0.41). When adjusted for diabetes duration, the significant association between the E/I ratio and aortic stiffness remained in diabetic women (r = -0.44, P = 0.008) and was stronger than the association between diabetes duration and aortic stiffness. There were no significant correlations between aortic stiffness and triglycerides or total cholesterol, respectively. CONCLUSIONS: Increased aortic wall stiffness found in women with Type 1 DM is related to diabetes duration. Further, in women with Type 1 DM there is a correlation between increased aortic stiffness and parasympathetic dysfunction. This may be of importance for the increased susceptibility to cardiovascular complications in diabetic women.

Factors predicting the diameter of the popliteal artery in healthy humans.

PURPOSE: To determine the relevance of popliteal dilatations, knowledge of the normal popliteal artery diameter is essential. This study investigates the diameter of the popliteal artery in healthy males and females. METHODS: We measured the diameter of the popliteal artery in 121 healthy volunteers (59 males and 62 females), ages 8 to 81, with echo-tracking B-mode ultrasonography. We analyzed the influence of age, sex, height, weight, body surface area (BSA) and systolic blood pressure with a multiple regression model. RESULTS: The popliteal artery increased steadily in diameter throughout life. From 25 years on, the diameter was larger in males than in females. If corrected for BSA, this difference decreased from 17% to 7%. This study found a correlation between popliteal artery diameter and BSA (r=0.47 and r=0.61, respectively, p < 0.0001). Age, followed by BSA, was the most influencing factor on popliteal diameter in both males and females (r=0.62 and r=0.66, respectively, p < 0.0001). We used age and BSA in creating a model for prediction of popliteal artery diameter. CONCLUSIONS: The diameter of the popliteal artery increases with age, initially during growth, but also in adults. This is related to age, body size and sex, with males having larger arteries than females. It is now possible to predict the normal popliteal arterial diameter, and nomograms are presented for use in the study of aneurysmal arterial disease.

Does long-term smoking affect aortic stiffness more in women than in men?

Smoking is a well-known risk factor for cardiovascular disease, although understanding of the pathophysiological mechanism is incomplete. The effect of heavy smoking, for more than 20 years and of 20 cigarettes per day, on aortic stiffness was studied in women (n = 23, age range 43-61 years) and men (n = 21, age range 43-61 years) who smoked but were otherwise healthy and compared with a healthy reference population that did not smoke. Aortic stiffness (beta) was calculated from the diameter and the pulsatile diameter change determined non-invasively using an ultrasonic echo-tracking system and blood pressure obtained by the auscultatory method. The results showed that aortic diameter did not differ in smoking males (P = 0.974) or in smoking females (P = 0.361). Aortic stiffness was increased in the female (P = 0.041) but not male smokers (P = 0.222). Systolic, mean and diastolic blood pressure in the men and women who smoked did not differ from those in the healthy reference population. In conclusion, this investigation shows increased aortic stiffness in female but not in male smokers. It indicates that the aorta of women might be more vulnerable to smoking with regard to stiffening and degeneration than the aorta of men.

Changes in aortic wall stiffness in men with alpha 1-antitrypsin deficiency.

OBJECTIVES: To examine the diameter and distensibility of the abdominal aorta in patients with severe alpha 1-antitrypsin deficiency, and to compare the results with those of normal subjects. MATERIAL AND METHODS: Abdominal aortic diameter and stiffness (beta) was measured using echo-tracking sonography in 19 men (mean age 50, range 25-79) and 17 women (mean age 46, range 26-62) with severe alpha 2-antitrypsin deficiency. The results were compared with those of healthy individuals of corresponding age and gender. RESULTS: There was no significant difference in the abdominal aortic diameter between controls and patients with alpha 1-antitrypsin deficiency when corrected for age, sex and body surface area (men p = 0.20, women p = 0.10). Men with alpha 1-antitrypsin deficiency showed significantly lower stiffness in the abdominal aorta compared to controls (p = 0.025), whereas women did not (p = 0.17). CONCLUSIONS: No significant difference in abdominal aortic diameter could be detected in patients with alpha 1-antitrypsin deficiency compared with controls. However, aortic distensibility in men with alpha 1-antitrypsin deficiency is altered. This may reflect early vessel wall abnormality.

Stiffness and diameter of the common carotid artery and abdominal aorta in women.

Vascular disease is differentiated throughout the vascular regions with aorta more prone to dilatation and with peripheral arteries more prone to occlusive disease. In this study, we investigated the diameter and distensibility in the common carotid artery (CCA) and abdominal aorta (AO) in healthy females of varying ages to assess potential differences in the aging process. The diameter and pulsatile diameter change of the CCA and AO in 66 healthy Caucasian females aged 8 to 79 y were examined using an ultrasound phase-locked echo-tracking technique. Blood pressure was obtained by the auscultatory method. Arterial stiffness (beta) was calculated. The diameter of both CCA and AO increases, not only in childhood, but also in adult women. The dilatation in adults (25 to 75 y) seems to be more pronounced in the AO (23%) than in the CCA (11%). Stiffness (beta) is higher in the CCA than AO before 20 y of age (p < 0.05). Stiffness increases with aging in both arterial regions, but the increase is initially somewhat higher in the AO, which means that no differences between the CCA and AO are seen from 25 y onward. In conclusion, this study demonstrates regional differences in diameter change and stiffness in the CCA and AO, and implies that the AO is more prone to age-related changes of the arterial wall than the CCA. These differences, however, are not as marked as previously reported in males.