High physical activity volume won’t worsen heart disease marker

High and very high volumes of leisure-time aerobic physical activity do not appear to contribute to coronary artery calcium (CAC) progression over time, according to a study.

Researchers looked at 8,771 apparently healthy men and women who were at least 40 years of age (mean 50.2 and 51.1 years, respectively) and had multiple preventive medicine visits at a single clinic, with a mean follow-up time of 7.8 years between the first and last clinic visit.

Physical activity and CAC measurements were obtained at each clinic visit. Physical activity was assessed continuously per 500 metabolic equivalent of task minutes per week (MET-min/wk) and categorized as follows: <1,500, 1,500–2,999, and ≥3,000 MET-min/wk.

Negative binomial regression was used to estimate the rate of mean CAC progression between visits, with potential modification by PA volume. Meanwhile, proportional hazards regression was used to estimate hazard ratios for baseline PA as a predictor of CAC progression to ≥100 Agatston units (AU).

The mean annual increase in CAC score was 28.5 percent for men and 32.1 percent for women, independent of physical activity. This translates to a difference in the rate of CAC progression per year of 0.0 percent per 500 MET-min/wk for both men and women.

Moreover, physical activity at baseline did not influence CAC progression to a clinically meaningful threshold of ≥100 AU over the follow-up period.

Analysis revealed that very high PA (vs referent) was not associated with CAC progression to 100 AU or more in men (hazard ratio [HR], 0.84, 95 percent confidence interval [CI], 0.66–1.08) or women (HR, 1.16, 95 percent CI, 0.57–2.35).