1、Therapeutic role of exercise in treating hypertension,Dalynn T. Badenhop, Ph.D., FACSM Professor of Medicine Director , Cardiac Rehabilitation Medical College of Ohio,Educational Objectives,To explain the acute blood pressure response to exercise To list the mechanisms by which exercise may improve
2、hypertension To apply exercise guidelines in treating hypertension To prescribe appropriate drug therapy for active hypertensive patients,Overview of Hypertension,High BP is a risk factor for stroke, CHF, angina, renal failure, LVH and MI Hypertension clusters with hyperlipidemia, diabetes and obesi
3、ty Drugs have been effective in treating high BP but because of their side effects and cost, non-pharmacologic alternatives are attractive,1997 JNC VI Classification of Blood Pressure,Overview of Hypertension,Joint National Committee VI (JNC VI) on Prevention, Detection, Evaluation, and Treatment of
4、 High Blood Pressure (1997) 50 million hypertensive patients in the U.S. National Health and Nutrition Examination Survey III (NHANES III) (1995) only 21% of treated hypertensive patients have BP controlled to 140/90 mm Hg 35% of hypertensive patients are unaware of their condition High-normal BP is
5、 associated with an incresed risk of cardiovascular disease N Eng J Med 2001; 345; 1291-7,Pathophysiology of Hypertension,Essential hypertension is characterized by increased DBP and related arteriolar vasoconstriction leading to increased SBP BP is mainly determined by cardiac output and total peri
6、pheral resistance High blood pressure may be linked to age-related vascular stiffening,Pathophysiology of Hypertension,High blood pressure is also associated with obesity, salt intake, low potassium intake, physical inactivity, heavy alcohol use and psychological stress Intra-abdominal fat and hyper
7、insulinemia may play a role in the pathogenesis of hypertension,Prevalence of Other Risk Factors With Hypertension,Kaplan NM. Dis Mon 1992; 38:769-838,Cardiovascular Consequences of Hypertension,Individuals with BP 160/95 have CAD, PVD & stroke that is 3X higher than normal HTN may lead to retinopat
8、hy and nephropathy HTN is also associated with subclinical changes in the brain and thickening and stiffening of small blood vessels,Cardiovascular Consequences of Hypertension,Increased cardiac afterload leads to left ventricular hypertrophy and reduced early diastolic filling Increased LV mass is
9、positively associated with CV morbidity and mortality independent of other risk factors High BP also promotes coronary artery calcification, a predictor of sudden death,Hypertension & CVD Outcomes,Increased BP has a positive and continuous association with CV events Within DBP range of 70-110 mm Hg,
10、 there is no threshold below which lower BP does not reduce stroke and CVD risk A 15/6 mm Hg BP reduction reduced stroke by 34% and CHD by 19% over 5 years,Lifestyle Changes for Hypertension,Reduce excess body weight Reduce dietary sodium to 2.4 gms/day Maintain adequate dietary intake of potassium,
11、 calcium and magnesium Limit daily alcohol consumption to 2 oz. of whiskey, 10 oz. of wine, 24 oz. of beer Exercise moderately each day Engage in meditation or relaxation daily Cessation of smoking,JNC VI Blood Pressure Classification,Medical Therapy and Implications for Exercise Training,Pharmacolo
12、gic and nonpharmocologic treatment can reduce morbidity Some antihypertensive agents have side-effects and some worsen other risk factors Exercise and diet improve multiple risk factors with virtually no side-effects Exercise may reduce or eliminate the need for antihypertensive medications,Acute BP
13、 Response to Exercise,Exaggerated BP Response to Exercise,Among normotensive men who had an exercise test between 1971-1982, those who developed HTN in 1986 were 2.4 times more likely to have had an exaggerated BP response to exercise Exaggerated BP response increased future hypertension risk by 300
14、% after adjusting for all other risk factors,Exaggerated BP Response to Exercise,Exaggerated BP was change from rest in SBP 60 mm Hg at 6 METs; SBP 70 mm Hg at 8 METs; DBP 10 mm Hg at any workload. Subjects in CARDIA study with exaggerated exercise BP were 1.7 times more likely to develop HTN 5 year
15、s later J Clin Epidemiol 51 (1): 1998,NIH Consensus Conference on Physical Activity and CV Health (1995),Review of 47 studies of exercise and HTN 70% of exercise groups decreased SBP by an avg. of 10.5 mm Hg from 154 78% of subjects decreased DBP by an avg. of 8.6 mm Hg from 98 Only 1 study showed i
16、ncreased BP w/ EX Beneficial responses are 80 times more frequent than negative responses Hagberg, J., et.al., NIH, 1995: 69-71,Increasing Lifestyle Activity for Patients with High-Normal Blood Pressure and Stage I Hypertension,Medical College of Ohio Study Group Kevin A. Phelps, D.O. Larry Johnson,
17、 M.D. Sandra Puczynski, Ph.D. Dalynn Badenhop, Ph.D. Michael McCrea Wendy Boone, RN, M.P.H,Lifestyle Activity vs. Structured Exercise,JAMA 1999; 281(4): 327-334 moderate-intensity lifestyle activity showed similar or better results versus structured exercise for improved cardiovascular fitness reduc
18、ed body fat decreased total cholesterol reduced blood pressure patient compliance In the past five years the Surgeon General, CDC, NIH, and ACSM have published position statements on the potential health benefits of lifestyle activity,Twenty-four week, physician-directed intervention program to lowe
19、r BP by increasing physical activityPatients randomized into two groups: Group 1 - educational intervention monitored via activity logs Group 2 - educational intervention monitored via activity logs and pedometer,Study Design,The Pedometer,a small device worn at the waist that counts steps used succ
20、essfully in obesity studies,Study Hypotheses,Adding a pedometer to goal setting will increase the level and frequency of physical activitywill improve BP control of adult patients with high-normal BP or Stage 1 HTN,Main Outcome Measures,Blood Pressure and BMI Physical Activity assessed by: two quest
21、ionnaires Physical Activity Recall Scale (PASE):assessed activity in past seven days Physician-based Assessment and Counseling for Exercise (PACE) :assessed readiness for change in level of physical activity,Patient Education Tool,Methods: Patient Identification,Potential subjects identified by char
22、t audit average BP of past three visits in High Normal BP or Stage 1 HTN category Exclusion Criteria: Antihypertensive med use confirmed BP 160/100 Dx DM, CHF, CAD, CVD, CA, MR pregnant child ( 18 yrs),Methods: Patient Recruitment,Identified subjects contacted during regularly scheduled physician vi
23、sitPhysician introduced study to patientInterested patients met with research assistant for more information about study,Methods: Patient Eligibility,Interested patients had two eligibility visits two weeks apart to confirm elevated BPIf average BP at two visits confirmed High-Normal BP or Stage 1 H
24、TN from chart audit, then patient was scheduled for first study visit (t0),Sample Characteristics,Methods: Study Visits,Research Assistant measured BP and weight, reviewed activity log at all visits administered PASE and PACE at baseline and completion Physician discussed barriers to increasing acti
25、vity new activity goal setting assisted with problem solving,Preliminary Results,Outcome measures analyzed at beginning of study, week 0 (t0) end of intervention period, week 12 (t1) end of maintenance period, week 24 (t2),Change in Systolic BP from Time 0 to Time 1 (12 weeks) for both groups,P = .0
26、05,Change in Systolic BP across time for both groups (24 weeks),Change in Diastolic BP from Time 0 to Time 1 for both groups (12 weeks),Change in Diastolic BP across time for both groups (24 weeks),Change in BMI across time for both groups (24 weeks),Change in PASE across time for both groups (24 we
27、eks),Preliminary Conclusions,Intervention alone (Group 1) did not significantly improve BPIntervention plus a pedometer (Group 2) significantly improved BP, but only with regular physician visits,Possible Mechanisms of BP Reduction with Exercise,Reduced visceral fat independent of changes in body we
28、ight or BMI Altered renal function to increase elimination of sodium leading to reduce fluid volume Anthropomorphic parameters may not be primary mechansims in causing HTN,Possible Mechanisms of BP Reduction with Exercise,Lower cardiac output and peripheral vascular resistance at rest and submaximal
29、 exercise Decreased HR Decreased sympathetic and increased parasympathetic tone Lower blood catecholamines and plasma renin activity,Antihypertensive & Volume Depleting Effects of Mild Exercise on Essential HTN,20 subjects with HTN (155/100) randomized to Exercise or Control group Cycle Ergometer Ex
30、ercise at Blood Lactic Acid Threshold for 60 min. 3X/wk for 10 weeks Changes in BP, hemodynamics and humoral factors of EX group compared with control group Urata, H., et. al. Hypertension 9:245-252,1987,Antihypertensive & Volume Depleting Effects of Mild Exercise on Essential HTN,Antihypertensive &
31、 Volume Depleting Effects of Mild Exercise on Essential HTN,Whole blood and plasma volume indices were significantly reduced (p 0.05) Change in serum Na+:serum K+ positively correlated with change in SBP Plasma NE concentrations at rest & Workload BLAT during GXTs were reduced Change in resting NE c
32、orrelated with change in mean BP Urata, H., et. al. Hypertension 9:245-252, 1987,Changes in Taurine & other Amino Acids in Response to Mild Exercise,Blood pressures were significantly decreased by 14.8/6.6 mmHg in the EX group but not the Control group Serum concentration increases of taurine (26%),
33、 cystine (287%), asparagine (11%), histidine (6%) and lysine (7%) in the EX Serum taurine was negatively correlated with the change in plasma NE Tanabe, Y, et. al., Clin & Exper Hyper 11:149-165, 1989,Changes in Taurine & other Amino Acids in Response to Mild Exercise,Exercise Prescriptions for Pati
34、ents With Borderline-to-Moderate Hypertension,Modified Naughton Treadmill Protocol,Exercise Prescriptions for Patients With Borderline-to-Moderate Hypertension,Exercise Prescriptions for Patients With Borderline-to-Moderate Hypertension,Excessive rises in blood pressure should be avoided during exer
35、cise (SBP 230 mm Hg; DBP 110 mm Hg). Restrictions on participation in vigorous exercise should be placed on patients with left ventricular hypertrophy.,Weight Training,Resistive exercise produces the most striking increases in BP Resistive exercise results in less of a HR increase compared with aero
36、bic exercise and as a result the “rate pressure product” may be less than aerobic exercise Assessment of BP response by handgrip should be considered in patients w/ HTN Growing evidence that resistive training may be of value for controlling BP Kelemen, et.al., JAMA 263:2766-71,1990,Drug Therapy for
37、 Active Hypertensive Patients,Hypertension only Thiazide diuretics in combination with a potassium supplement are effective and inexpensive Diuretics limit plasma volume expansion and decrease peripheral resistance Other antihypertensive drugs can be used as monotherapy for this type of patient,Drug
38、 Therapy for Active Hypertensive Patients,Hypertension with other diseases CAD - calcium-channel blocker or a beta- blocker Diabetes - ACE inhibitor LVH but coughs with ACE inhibitor - angiotensin-2-receptor blocker Elderly men with prostatism - peripheral alpha-blocker (terazosin, doxazosin),Drug T
39、herapy for Active Hypertensive Patients,Beta1-selective blockers such as atenolol or metoprolol are preferable to non-selective agents such as propranolol, nadolol or pindolol for hypertensive patients engaged in regular exercise Kaplan, N.M., Am J Hypertens 2:75-77,1989,Beta-blocker therapy and exe
40、rcise,Non-selective Beta-blockers may increase a patients disposition to exertional hyperthermia. So patients should adhere strictly to guidelines for fluid replacement Patients should use fluid replacement drinks with low concentrations of K+ to avoid the risk of hypokalemia Gordon, N.F., Am J Card
41、iol 55: 74-78,1985,Beta-blocker therapy and exercise,Exercise therapy is desirable during Beta-blocker therapy to offset the adverse alterations in lipoprotein metabolism contributed by some Beta-blocker medicationsGordon, N.F., Compr Ther 14: 52-57, 1988,Beta-blocker therapy and exercise,Exercise i
42、ntensity for patients on Beta-blocker medications should be in accordance with traditional guidelines based on the results of individualized exercise testing performed on the medication.American College of Sports Medicine Guidelines for Exercise Testing and Prescription, 2000,Beta-blocker therapy an
43、d exercise,Non-selective Beta-blockers dramatically reduce peak aerobic capacity and at the same time increase a patients rating of perceived exertion for a given amount of work.Kaplan, N.M., Am J Hypertens 2:75-77,1989,Beta-blocker therapy and exercise,Patients treated with Beta-blockers are capabl
44、e of deriving the expected enhancement of cardiorespiratory fitness during training, irrespective of the type of drug usedBlood, S.M., J Cardiopulmonary Rehabil 8: 141-144, 1988,SUMMARY,Physical activity has a therapeutic role in the treatment of hypertension No consistent relationship between reduc
45、ed weight and lower BP Exercise at lower intensities is effective in treating mild to moderate hypertension Exercise testing may help identify exaggerated BP responses to exercise,SUMMARY,Exercise prescription for HTN should be based on medical hx and risk factor status Exercise prescription should
46、be adapted to antihypertensive medications that may affect exercise HR, BP & performance Incorporating resistive training into the exercise prescription may be of value for controlling blood pressure,References,Chintanadilok, J., Exercise in Treating Hypertension, PhysSports Med 30: 11-23, 2002 Urat
47、a, H., Antihypertensive and Volume-Depleting Effects of Mild Exercise on Essential Hypertension, Hypertension 9: 245-52, 1987. Tanabe, Y., Changes in Serum Concentration of Taurine and Other Amino Acids in Clinical Antihypertensive Exercise Therapy, Clin and Exper Hyper A11: 149-165, 1989. American College of Sports Medicine, Physical Activity, Physical Fitness and Hypertension, Med Sci Sports Exerc 25: i - x , 1993. ACSMs Resource Manual for Guidelines for Exercise Testing and Prescription, Baltimore, Williams & Wilkins, p. 275-280, 1998.,
