The mechanisms mediating the more striking age related increase in cardiovascular disease in women than in men are poorly understood. We tested the hypothesis that aging has a greater impact on sympathetic traffic in women than in men. Muscle sympathetic nerve activity (MSNA), blood pressure, and heart rate were measured in 120 healthy males and 96 healthy females aged 20 to 72 years. MSNA increased with age in both sexes, but age explained 53% of MSNA variance in female subjects and only 8% of MSNA variance in male subjects. Both the slope and intercept of the regression lines were significantly different between male and female groups ( P <0.01 and P <0.001, respectively). For each decade of life, women showed an increase of 6.5 bursts/min in comparison to an increase of 2.6 bursts/min in males. Menopause did not explain the age-related increase in sympathetic traffic. For every 10-burst/min increment in MSNA in subjects older than 40, mean blood pressure increased by 2.7 mm Hg in men and by 6.1 mm Hg in women. Aging is accompanied by a greater increase in sympathetic traffic in women than in men, independent of menopausal status. Sympathetic neural mechanisms may contribute importantly to the more marked influence of age on blood pressure and cardiovascular disease in women.

A wide range of definitions is used to distinguish subjects in whom blood pressure (BP) falls at night (dippers) from their counterparts (nondippers). In an attempt to standardize the definition of nondipping, we determined the nocturnal BP fall and night-day BP ratio by 24-hour ambulatory monitoring in 4765 normotensive and 2555 hypertensive subjects from 10 to 99 years old. In all subjects combined, the systolic/diastolic nocturnal fall and corresponding ratio averaged (±SD) −16.7±11.0/−13.6±8.1 mm Hg and 87.2±8.0%/83.1±9.6%, respectively. In normotensive subjects, the 95th percentiles were −0.3/−1.1 mm Hg for the nocturnal fall and 99.7%/98.3% for the night-day ratio. Both the fall and ratio showed a curvilinear correlation with age. The smallest fall and largest ratio were observed in older (≥70 years) subjects. A higher BP on conventional sphygmomanometry was associated with a larger systolic (partial r =.11) and diastolic ( r =.12) nocturnal BP fall. The diastolic ( r =.08) but not the systolic night-day ratio increased with higher conventional BP. The nocturnal BP fall was larger and the corresponding night-day ratio smaller in oscillometric (n=5884) than in auscultatory (n=1436) recordings, in males (n=3730) than in females (n=3590), and in Europe (n=4556) than in the other continents (n=2764). The distributions of the nocturnal BP fall and night-day ratio showed considerable overlap among normotensive and hypertensive subjects, but the overlap tended to be larger for the ratio than for the fall. Of all subjects, 3.2% had systolic and diastolic ratios of 100% or more. With adjustments applied for confounders, the probability of being a nondipper increased 2.8 times (95% confidence interval, 2.0-4.0) from 30 to 60 years and 5.7 times (4.4-7.4) from 60 to 80 years. The odds ratios were 1.0 (0.8-1.4) for males versus females, 1.6 (1.2-2.1) for subjects with definite hypertension versus normotensive subjects, 2.4 (1.2-4.7) for Asians (n=2213, 96% Japanese) versus inhabitants of the other continents, and 2.4 (1.5-3.8) for subjects examined with auscultatory versus oscillometric devices. In conclusion, the mathematical definition of nondipping, ie, having a night-day ratio of 100% or more for systolic and diastolic BPs, closely approximated the 95th percentiles of the night-day ratio in normotensive subjects. The ratio depends less on BP level than the nocturnal BP fall and is therefore to be preferred in the definition of dipping status. Notwithstanding the present findings, the reproducibility of nondipping and its prognostic significance need further clarification.

Carotid–femoral pulse wave velocity (PWV) has been shown to be a powerful predictor of cardiovascular morbidity and mortality. Sympathetic neural mechanisms may have a stiffening influence on arterial mechanical properties. The relationship between direct measures of sympathetic traffic and PWV in healthy humans has not been previously studied. We, therefore, tested the hypothesis that PWV is independently linked to muscle sympathetic nerve activity (MSNA) in normal individuals. We measured MSNA (microneurography), PWV (Complior device), heart rate and blood pressure in 25 healthy male participants (mean age 43 ± 10 years). PWV correlated significantly with age (r = 0.63, P < 0.001), SBP (r = 0.43, P < 0.05) and MSNA (r = 0.43, P < 0.05) but not with BMI, waist circumference, waist-to-hip ratio, heart rate, pulse pressure or DBP. Robust multiple linear regression analysis revealed that only age and MSNA were linked independently to PWV (r 2 = 0.62, P < 0.001), explaining 39 and 25% of its variance, respectively. After adjustment of PWV for age and SBP, we further divided individuals into ‘excessive’ PWV (i.e. higher than expected from age and SBP) and ‘optimal’ PWV (i.e. lower than expected). BMI and blood pressure were similar in both subgroups. Individuals with excessive PWV had significantly greater MSNA than individuals with optimal PWV (30 ± 10 vs. 18 ± 11 bursts/min, P = 0.01). This study provides the first evidence that PWV is linked to MSNA in normal humans. The relationship between MSNA and PWV is independent of age, BMI, waist circumference, waist-to-hip ratio, heart rate, pulse pressure or blood pressure.

Achievement of complete donor hematopoietic chimerism (CC) is the goal of allogeneic stem cell transplantation (allo-SCT). Persistence of recipient hematopoiesis augments the risk of relapse, which is one of the main reasons for mortality after allo-SCT. Another main reason for morbidity and mortality is severe extensive chronic graft-versus-host disease (cGvHD). We examined chimerism in peripheral blood of 54 allogeneic stem cell recipients using multiplex STR-PCR method and compared it with the timing and severity of cGvHD. In total, 25 patients achieved early CC (by day 100 post transplant) at a median time of 60 days. In total, 21 of them developed extensive cGvHD. In those patients CC uniformly preceded emergence of cGvHD by a mean of 85 days. A total of 26 patients obtained late CC at a median time of 270 days post transplant. Of this group, only eight patients developed extensive disease. Development of cGvHD in those patients preceded achievement of CC in 10 of 13 cases by a mean of 100 days. The difference between early and late CC groups as to the frequency of the extensive cGvHD was statistically significant (P<0.001). Also, there was a significant correlation of the time of CC and time between CC and cGvHD. Additionally, patients with early CC developed significantly more severe cGvHD measured by the need of three-drug treatment to control the disease (P<0.005). It can be concluded that achievement of early complete donor hematopoietic chimerism in peripheral blood is strongly predictive of severe extensive GvHD.

Although headache is regarded a symptom of hypertension, its relation to blood pressure, especially in mild and moderate hypertension, is not clear. Thus, the aim of the study was to investigate whether headache in patients with mild to moderate hypertension may be attributed to simultaneous elevations in blood pressure. Ambulatory blood pressure monitoring (ABPM) was performed in patients (mean age 48 ± 10 years, n = 150, 92 men, 58 women) classified, according to their office blood pressure, as stage 1–2 hypertensives (JNC VI). Headache periods were recorded in patients' diaries. Headaches were generally not directly associated with blood pressure elevations in the studied group of stage 1–2 hypertensive patients because (i) blood pressure values from headache periods were not significantly higher than those from headache-free periods; (ii) blood pressure values directly preceding the pain were not significantly different from values at the beginning of headache; and (iii) in the vast majority of hypertensives, their maximal blood pressure values were recorded during headache-free periods. Moreover, in some instances, patients who showed maximal ABPM values during headache had relatively high blood pressure, i.e. ≥ 180/110 mmHg. Our results did not support the opinion that headache experienced by stage 1–2 hypertensives was generally caused by simultaneous elevation in blood pressure. The direct mechanisms of headache in hypertension, as well as the relation between increments in blood pressure above 180/110 mmHg and headache, need further investigations.