Hypertension in the elderly

Nutrition and diseases of women: cardiovascular disorders

Studies of prevention, diagnosis, and intervention for coronary heart disease and hypertension have either been conducted largely in men, or gender differences have not always been fully sought. This has added to a general perception that coronary artery disease is basically a male affliction despite the fact that coronary artery disease is the leading cause of death among women, especially elderly women. Many risk factors among women are similar to men, i.e., high blood pressure (BP), elevated serum cholesterol levels, and cigarette smoking; however, women compared to men have greater incidence of diabetes mellitus, congestive heart failure, and hypertension as they become older. The risk of cardiovascular disorders can be reduced by postmenopausal estrogen replacement, exercising sufficiently, and ceasing smoking. In addition, good nutrition, taking into consideration the proper amount and forms of calories, sodium, potassium, calcium, magnesium, and macronutrients to maintain an ideal lipid profile and BP, is helpful in preventing cardiovascular perturbations.

A review of persistent, low-grade lead challenge: neurological and cardiovascular consequences

Although acute toxicity following heavy intake of lead (Pb) is a well-established clinical entity, the harmful effects of persistent, low-dose challenge, a situation commonly found among the general population, is uncertain. The major dangers of persistent, low-dose challenge that have been hypothesized are controversial: first, mentation and behavioral perturbations and second, development of hypertension with its consequences on the cardiovascular system. Accordingly, one cannot exclude some contributions from persistent Pb exposure to chronic disease and the aging process. Despite these potential adversities, many sources for Pb contact still remain with us. Current estimates are that 10-50% of American children (over 3-4 million) harbor unsafe levels according to present-day standards. Therefore, it is reasonable to conclude that more work is needed in this area. Clearcut evidence concerning the deleterious influence of Pb on the nervous and/or cardiovascular-renal systems would lead to greater attempt to lessen exposure, to ameliorate symptomatology by providing supplemental agents which obviate the unwanted effects of Pb (iron, calcium, zinc), and to consider therapy with binding agents, like CaNa2EDTA, in the afflicted.

The efficacy of a transdermal formulation of clonidine in mild to moderate hypertension and its effects on the arterial and venous vasculature of the forearm

We have studied the efficacy of clonidine hydrochloride administered transdermally once a week for 9 to 15 weeks in 12 patients with mild to moderate hypertension. Clonidine reduced both supine and standing blood pressures on average, but only 8 subjects were responders, i.e. had a decrease in supine diastolic blood pressure to below 90 mm Hg or more than 10% from baseline. Supine heart rate was unchanged, but in the responders the orthostatic increase in heart rate was reduced by clonidine from baseline (p less than 0.05). Moreover, in all the patients the change in the orthostatic increase in heart rate was correlated with the change in supine diastolic pressure (p less than 0.05). Brachial artery blood flow, forearm arterial compliance, vascular resistance, and venous tone were not affected by clonidine. Thus, transdermal clonidine reduced blood pressure, probably by a baroreflex-mediated effect, but did not affect the vasculature of the forearm.

Direct and indirect blood pressure during exercise

In 27 subjects, we compared rest and exercise blood pressure (BP) measurements determined directly by catheterization of the radial artery with simultaneous values obtained indirectly by auscultation of the brachial artery. As work increased, the systolic BP increased, whereas the diastolic BP did not change. Considering all comparisons, direct BP was greater than indirect BP by a mean of 29.0 mm Hg for systolic BP and 12.3 mm Hg for diastolic BP. As exercise level increased, the difference between direct and indirect systolic BP decreased whereas the difference between direct and indirect diastolic BP did not change. Both methods have advantages for assessment of BP response to exercise: normality of BP response is best assessed by auscultation, whereas beat-by-beat trends in BP are more accurately defined by the direct method.

Regional compliance of brachial artery and saline infusion in patients with arteriosclerosis obliterans

Simultaneous brachial artery pressure and blood flow measurements were made in 15 patients with arteriosclerosis of the lower limbs (AOLL) and in controls of the same age and sex. Blood flow was evaluated by a pulsed Doppler device with a double-transducer probe. From analysis of the pressure-flow curves during diastole, regional arterial compliance (RAC) was determined by using as a model of the forearm arterial tree a system of tubes, each with a storage capacity, in series with the arteriolar resistance vessels. In AOLL patients, RAC was significantly reduced (102 +/- 13 vs 173 +/- 14.10(-4) ml/mm Hg, p less than 0.01), and systolic pressure was significantly increased. After saline infusion, systolic pressure continued to increase and arterial compliance, to decrease; brachial blood flow did not change. Study of the baroreflex sensitivity in AOLL patients under basal conditions indicated that a higher pulse pressure was required to obtain the same heart rate as in the controls. The study provided evidence that in AOLL patients: 1) compliance was reduced in the brachial artery (a regional circulation with no clinical evidence of arterial occlusion); 2) an increase in systolic pressure resulted from the decreased arterial compliance; and 3) saline infusion exaggerated the observed reduction in arterial compliance and increase in systolic pressure.