Hypertension restricts leg blood flow and aggravates neuromuscular fatigue during human locomotion in males.

Patients with hypertension (HTN) are characterized by exaggerated vascular resistance and mean arterial pressure (MAP) and a compromised leg blood flow (QL) response to exercise recruiting a small muscle mass. However, the impact of hypertension on peripheral hemodynamics and the development of neuromuscular fatigue during locomotor activities, which critically depends on QL, remain unknown. Eight HTN (143 ± 11 mmHg/95 ± 6 mmHg; 45 ± 13 yr) and eight matched (age and activity) controls (120 ± 6 mmHg/77 ± 7 mmHg; CTRL) performed constant-load cycling exercise at 25, 50, and 75 W (for 4 min each) and at 165 ± 41 W (for 5 min). Exercise-induced locomotor muscle fatigue was quantified as the pre- to postexercise change in quadriceps twitch-torque (ΔQtw, peripheral fatigue) and voluntary activation (ΔVA%, central fatigue). QL (Doppler ultrasound) and leg vascular conductance (LVC) were determined during cycling at 25, 50, and 75 W. Heart rate and ventilatory responses were recorded during all intensities. MAP during exercise was, on average, ∼21 mmHg higher (P = 0.002) and LVC ∼39% lower (P = 0.001) in HTN compared with CTRL. QL was consistently between 20 and 30% lower (P = 0.004), and heart rate was significantly higher in HTN. Exercise-induced peripheral (ΔQtw: -53 ± 19% vs. -25 ± 23%) and central (ΔVA%: -7 ± 5% vs. -3 ± 2%) fatigue was significantly greater in HTN compared with CTRL. In addition to an exaggerated MAP, LVC and QL were lower during exercise in HTN compared with CTRL. Given the critical role of QL in determining the development of neuromuscular fatigue, these hemodynamic impairments likely accounted for the faster development of neuromuscular fatigue characterizing hypertensive individuals during locomotor exercise. NEW & NOTEWORTHY The impact of primary hypertension on the cardiovascular and neuromuscular fatigue response to locomotor exercise is unknown. We compared central and peripheral hemodynamics and the development of central and peripheral fatigue during cycling exercise in patients with stage I/II hypertension and age- and activity-matched healthy individuals. In addition to a significantly elevated blood pressure, hypertensive patients were, compared with their nonhypertensive counterparts, also characterized by considerable leg blood flow limitations and impaired neuromuscular fatigue resistance.

Hypertension in the geriatric population: a patient-centered approach.

Hypertension contributes greatly to adverse cardiovascular outcomes; the magnitude of this contribution increases with age. The most recent guideline has proposed raising the goal systolic blood pressure to less than 150 mm Hg among those over age 60; however, this recommendation is not endorsed by other organizations. There are multiple contributors to hypertension in the older individual, including increased vascular stiffness, salt sensitivity, and decreased baroreceptor responsiveness. Therapy in the hypertensive patient over age 60 should be individualized and account for patient's health, functional and cognitive status, comorbidities, frailty, and prognosis.

Hypertension and chronic kidney disease in the elderly.

Although age-related alterations in the structure and function of the kidney may be inevitable, up to one-third of the older population shows no age-related decline in kidney function. As measured by inulin clearance, the healthy elderly population will be able to maintain a normal, albeit lower than their younger counterparts, glomerular filtration rate. This age-related decline in glomerular filtration rate will remain clinically insignificant in the absence of acute or chronic conditions adversely affecting kidney function or reserve. The contribution of illnesses associated with aging, such as hypertension (HTN) and diabetes mellitus, may accelerate this decline in kidney function with aging and therefore increase the incidence of chronic kidney disease. With the predicted global increase in the elderly population, the effect on health care costs and on society in general will be enormous. This will require intensive efforts at controlling diseases, such as HTN, along with continued efforts at promoting increased aerobic exercise, and a low sodium, low fat diet. The age-related decline in kidney function will, in turn, affect not only the choice of therapeutic agent in the treatment of HTN but the dosing and need for combination therapy as well. Although these approaches will need to be as aggressive as possible, they will also need to be balanced with the individual patient's potential for adverse outcomes such as orthostatic hypotension, worsening kidney function, and hyperkalemia (depending upon the agent chosen).

Practical recommendations for treatment of hypertension in older patients.

BACKGROUND: By the year 2030 the percent of the population over the age of 65 years is projected to range from 3.7% (in sub-Saharan Africa) to almost 22% (in Europe). Accompanying this unprecedented growth will be a significant increase in many of the disease processes or "comorbidities" associated with aging, not the least of which is hypertension. Global health care resources and economies in general will be stressed to breaking point if this condition is not dealt with in an aggressive and timely manner because the consequences of untreated hypertension such as stroke, myocardial infarction, and dementia are exceedingly costly in the long term. METHODS: To help focus attention on the worldwide epidemic of hypertension, the current literature and guidelines were reviewed, along with information on the various classes of medications indicated in the treatment of hypertension in the elderly. RESULTS: Recent, large, randomized trials indicate that hypertension in the elderly can and should be treated to lower the incidence of stroke, myocardial infarction, and chronic kidney disease. Although thiazide-type diuretics are the recommended first-line agents in most cases of uncomplicated hypertension, multiple drug classes have been shown to be useful. In addition, and where feasible, a multidisciplinary team approach has demonstrated the most durable results. CONCLUSION: Thiazide diuretics should be the first-line agents in uncomplicated, isolated systolic hypertension. Starting at low doses and proceeding in a gradual manner, these agents have proven efficacy in decreasing the risk of stroke and cardiovascular events. It is now recommended that these agents be used in low-dose combinations with other antihypertensive drug classes in patients who do not achieve target blood pressure (<140/90 mmHg).

Spironolactone and hydrochlorothiazide decrease vascular stiffness and blood pressure in geriatric hypertension.

OBJECTIVES: To determine the efficacy of spironolactone (SPIRO) and hydrochlorothiazide (HCTZ) as monotherapy in older patients with hypertension in blood pressure (BP) control and measures of vascular stiffness. DESIGN: Randomized double-blind trial. SETTING: University teaching hospital. PARTICIPANTS: Forty-five subjects with hypertension (24 men, 21 women, mean age 69). INTERVENTION: Six months of HCTZ (n=21) or SPIRO (n=24) therapy titrated to a target systolic BP (SBP) less than 140 mmHg. MEASUREMENTS: Baseline (after 4 weeks of antihypertensive drug washout) and 6-month 24-hour ambulatory BP data were obtained. Pulse pressure (PP) was calculated as the difference between 24-hour average SBP and DBP. Pulse wave velocity (PWV) was determined according to noninvasive recordings of carotid and femoral artery pulse waves. RESULTS: Six months of HCTZ and SPIRO treatment was associated with significant decreases in 24-hour and nocturnal SBP and diastolic BP (DBP) (analysis of variance (ANOVA) P<.001). At 6 months, average 24-hour and nocturnal SBP were lower in the SPIRO than the HCTZ group (P<.001). PP and PWV also decreased significantly with HCTZ and SPIRO treatments (ANOVA P<.001). CONCLUSIONS: Six months of therapy with HCTZ or SPIRO resulted in comparable reductions in 24-hour average and nocturnal SBP and DBP, PP, and PWV in older subjects with hypertension.