Gymnastik- och idrottshögskolan, GIH

BACKGROUND: There are no diagnosis-specific guidelines for moderate-to-vigorous physical activity (MVPA) and sedentary behaviour (SB) for coronary heart disease (CHD). This study aims identifying thresholds of MVPA and SB associated with cardiovascular events.

METHODS: Cohort study including individuals with CHD. MVPA and SB were self-reported, and health registers identified cardiovascular events (2006-2022). Survival tree analyses identified thresholds of time associated with the risk of cardiovascular events. Thresholds were explored in Cox regression models.

RESULTS: There were 40,156 Australians, 62% men, mean age 70 years. Over 8.3 median years, 3260 non-fatal cardiac events, 5161 total cardiac events, and 14,383 major adverse cardiovascular events (MACE) occurred. Thresholds for MVPA were 122 minutes/week for non-fatal cardiac events and 94 minutes/week for total cardiac events and MACE. Meeting MVPA thresholds was associated with an 18% lower risk for non-fatal cardiac events, 29% lower risk of total cardiac events, and 23% lower risk of MACE than not reaching the thresholds. Thresholds for SB were 4 and 10 hours/day respectively for risk of total cardiac events and MACE. SB below thresholds was associated with a 14% lower risk of total cardiac events and an 18% lower risk of MACE. There were sex-specific thresholds for MVPA and SB.

CONCLUSION: To lower cardiovascular event risk, identified MVPA thresholds were lower (94-122 minutes/week) than the public health guidelines (150 minutes/week) in individuals with CHD. The SB thresholds associated with a lower risk of total cardiac events and MACE varied between 4-10 hours/day.