Exercise as a medicine for cardiovasular protection

Expert Opinion: CHD Prevention • US Surgeon General 1996 • Significant health benefits primarily cardiovascular from moderate amounts of daily physical activity • 30 minutes brisk walkin

Exercise as a Medicine for

Cardiovasular Protection

Thomas G Allison, PhD, MPH, FACC

Mayo Clinic, Rochester, MN

VNHA – Da Nang

October, 2014

No Disclosures

Question 1: Does Exercise Prevent CVD

over a Lifetime in Healthy People?

→

This is principally an epidemiologic question

Large, long-term randomized trials are not feasible

Expert Opinion: CHD Prevention

• US Surgeon General 1996

• Significant health benefits (primarily

cardiovascular) from moderate amounts of daily physical activity

• 30 minutes brisk walking or raking leaves,

• 15 minutes running

• 45 minutes sports

• More exercise is better

• How many of you follow this recommendation?

Question 2: Does exercise reduce clinical

events and increase quality adjusted life

years in patients with CVD and diabetes?

versus Versus

Stress test 1

Stress test 2

Effect of Exercise on Coronary Artery

Disease Progression

Schuler et al doi:10.1093/eurheartj/eht111; April 7, 2013

Placebo Metformin Diet/exercise

Knowler, WC et al, NEJM 2002;364:393-403

LOOK AHEAD Research Group N Engl J Med 2013;369:145-54

LOOK AHEAD TRIAL: Primary Composite Outcome

LOOK AHEAD Research Group N Engl J Med 2013;369:145-54

• 27 patients with stable, post-infarction systolic HF

• Randomized

1) Moderate continuous training (MCT) 2) Aerobic interval training (AIT)

3) Control

• 3 x week for 12 weeks

• No deaths or untoward events

Wisloff Circulation 2007;115:3086

Exercise Training in Heart Failure

Surrogate Endpoints: Favorable Remodeling

Results

Wisloff Circulation 2007;115:3086

O’Connor CM et al JAMA 2009;301:1439-1450

Exercise Training in CHF: Mortality

and Morbidity Effects

Exercise is great medicine, but sometimes

it can be a hard pill to swallow

Explains negative results in LOOK AHEAD and HF-ACTION

Conclusions

• Exercise appears to be potentially good

medicine for CV prevention

• Strong epidemiological evidence for primary

prevention of CAD and diabetes

• Beneficial effects on risk factors

number, size, and methodology

exercise programs likely limits benefit

• Supervised programs seem to superior to home

programs

• No evidence of harm despite exercise paradox

Living Under the

• Comments?

• Questions?

• Contact:

allison.thomas@mayo.edu

Benefits of Physical Activity on Coronary Risk Factors

• Improved blood lipids

 HDL-cholesterol

 Triglycerides

 Small, dense LDL-cholesterol

• Decreased blood pressure

~ 4/4 mmHg in normotensive subjects

~ 11/6 mmHg in hypertensive subjects

• Improved insulin resistance

• Reduced visceral adiposity

• Reduced hs-CRP

Effect of Exercise on Coronary Artery

• 113 patients with stable angina randomized

• 12 month training program versus usual care

Meta-Analysis: Exercise for 2° CHD

• No evidence of reduction in non-fatal CHD

Jolliffe et al, The Cochrane Library 2003:Issue 4

Effect of Aggressive Lifestyle Management

on Symptom Burden and Severity in

Patients with Atrial Fibrillation

• 150 patients with history of atrial fibrillation but

currently in sinus rhythm

• Randomized to aggressive lifestyle

management versus usual care + fish oil 3g/day

• Lifestyle management program

• Phase 1: low calorie diet + light exercise program for

8 weeks

• Phase 2: low glycemic diet + vigorous exercise

program

• Patients kept diet and activity diary

Abed H et al JAMA 2013;310:2050-2060

Outcomes

Abed H et al JAMA 2013;310:2050-2060

LOOK AHEAD Trial

Does an exercise + diet intervention prevent CV

events in Type 2 diabetics?

• 5145 overweight or obese patients with type 2

diabetes

• Intervention group

• Intensive lifestyle intervention that promoted weight

loss through decreased caloric intake and increased

physical activity

• Control group

• Diabetes support and education

LOOK AHEAD Research Group N Engl J Med 2013;369:145-54

LOOK AHEAD TRIAL

• Primary outcome composite of death from CV

causes, nonfatal myocardial infarction, nonfatal

stroke, or hospitalization for angina

• Maximum follow-up 13.5 years

• Trial was stopped early on the basis of a futility

analysis when the median follow-up was 9.6

years

LOOK AHEAD Research Group N Engl J Med 2013;369:145-54

Exercise Training in CHF: Mortality and

Morbidity Effects

• HF ACTION:

• RCT: usual care vs structured exercise training;

50 sites in US and Canada

• 5-year follow-up

• Outcomes = death, hospitalization

O’Connor CM et al JAMA 2009;301:1439-1450

HF-ACTION Results

• N = 2,331

• 6 minute walk distance: Δ = 12 vs 13 meters

• Peak VO2: Δ = 0.1 vs 0.7 mL/kg/min

• All-cause mortality: no difference

• Modest reduction in clinical events

O’Connor CM et al JAMA 2009;301:1439-1450

Question 3: What is the effective dose of

exercise?

Recommendations

• Assess the potential impact of increased

physical activity for the individual patient

• Start with a level of exercise appropriate to the baseline fitness and activity level of the patient

• Progressively advance the exercise

prescription until risk factors are optimally

controlled … or limits of tolerance are reached

Recommendations

Amount of exercise

• “Vigorous” exercise (like jogging) for 30 minutes at least 2-4 times per week

• At least 2000 kcal/week in leisure-time physical

activity (like brisk walking)

• Achieve an exercise capacity of 10 METs for men

or 9 METs for women

Recommendations

Exercise intensity

• Relative exercise intensity of 4 (“somewhat

strong”) on the 10-point Borg scale

• 12-14 on the older 6-20 Borg scale

Type of exercise

• Running, jogging, walking, rowing, weight training have all been validated

• Other forms or aerobic exercise likely beneficial

• “Reasonable” to do resistance training 2-3 times per week

Implications of Recent Trials

• High intensity interval training more effective

than continuous low-moderate intensity training

• Supervised training superior to home programs

• Both HF-ACTION and LOOK AHEAD had more

frequent supervised sessions initially, tapering off to

home program as study progressed