The relationship between Exercise and Heart Disease – Does Genetics Matter?
BACKGROUND AND PURPOSE:
- Previous studies on fitness and cardiovascular disease (CVD) tend to rely on small sample sets and rely on self-reporting
- Tikkanen et al. (Circulation 2018) determined the effectiveness of physical activity in preventing cardiovascular disease in those predisposed due to genetic factors
METHODS:
- Large longitudinal cohort study
- Individuals 40 to 69 years of age enrolled in the UK Biobank cohort study (2006 to 2010)
- Includes detailed health assessments and collection of blood, urine, and saliva samples
- Participants agreed to have their future health/disease events followed and monitored
- Data collected include grip strength, objective and subjective physical activity, and cardiorespiratory fitness along with cardiovascular events and all-cause death
- Associations were further examined in individuals with different genetic burden by stratifying individuals based on their genetic risk score for coronary heart disease and atrial fibrillation
- Disease risk was compared between individuals in different tertiles (data broken down in to 3 parts each containing a 3rd of the population) of fitness, physical activity, and genetic risk
- Statistical analysis was based using hazard ratio (HR)
RESULTS:
- The UK biobank incudes 502,635 participants and 54% were women
- Grip strength, physical activity, and cardiorespiratory fitness showed inverse associations with incident cardiovascular events
Coronary Heart Disease
- Grip strength: HR 0.79 (95% CI, 0.77 to 0.81)
- Physical Activity: HR 0.95 (95% CI, 0.93 to 0.97)
- Cardiorespiratory fitness: HR 0.68 (95% CI, 0.63 to 0.74)
Atrial Fibrillation
- Grip strength: HR, 0.75 (95% CI, 0.73 to 0.76)
- Physical activity: HR 0.93 (95% CI, 0.91 to 0.95)
- Cardiorespiratory: HR 0.60 (95% CI, 0.56 to 0.65)
- Higher grip strength and cardiorespiratory fitness were associated with lower risk of incident coronary heart disease and atrial fibrillation in each genetic risk score group (Ptrend <0.001 in each genetic risk category)
- In particular, high levels of cardiorespiratory fitness were associated with 49% lower risk for coronary heart disease (HR, 0.51; 95% CI, 0.38 to 0.69) and 60% lower risk for atrial fibrillation (HR, 0.40; 95%, CI 0.30 to 0.55) among individuals at high genetic risk for these diseases
CONCLUSION:
- Physical activity demonstrates inverse correlations with incident cardiovascular disease in not only in the overall population, but especially in those with genetic risk as well
