Written by Chrystal Moulton, Science Writer. Every additional hour of sedentary time above 10.6 hours/day was significantly associated with an increased risk of heart failure and cardiovascular disease mortality (P <0.05).
Sedentary behavior is associated with an increased risk of incident cardiovascular disease1,2. In the US, adults engaged in sedentary behavior on average 9.5 hours per day3. Understanding the specific levels of inactivity associated with specific cardiovascular disease risk is still ongoing4. A recent study showed that for every 1 hour increase per day in sedentary behavior, there was a 5% higher risk of overall cardiovascular disease5. In the current study, researchers utilized data from the UK biobank to investigate the relationship between sedentary behavior and the prospective risk of cardiovascular disease mortality, atrial fibrillation, myocardial infarction, and heart failure6.
The UK biobank is a prospective cohort containing more than 500,000 participants between the ages of 40 and 69 years old who reside in England, Wales, and Scotland. Researchers used physical examinations and questionnaires to collect information from participants and outcomes were examined through the National Health related data sets (death and medical records). Data from a subset of participants was evaluated specifically for this study. Between 2013 and 2015, subjects were invited to participate in a sub-study where they were required to wear an accelerometer for seven days. This device captured all activity including sleep, light physical activity, moderate to vigorous physical activity, and sedentary activity. Machine learning models were used to organize and analyze the information from the accelerometer. Individuals were followed up from the end of the 7th day after wearing the accelerometer until either their death, a cardiovascular disease outcome occurred, or the end of the trial in their designated region. Individuals were categorized into four groups based on sedentary time. Quartile 2 (8.2- 9.4 hours/ day) was used as the reference group. Researchers then chose 10.6 hours/ day as a threshold to assess the relationship between sedentary time and the risk of either heart failure, myocardial infarction, atrial fibrillation, and cardiovascular disease mortality. Thus, outcomes were assessed above and below 10.6 hours/day. Models were adjusted based on confounding factors and sensitivity analysis was also conducted.
Of 103,691 individuals in the accelerometer sub study, data from 89,530 individuals was included in this analysis. The average age of participants was 62 ±8 years old and the median sedentary time was 9.4 hours/ day. Median follow-up time was 8 years During which:
- 1610 individuals experienced incident myocardial infarction
- 846 died of cardiovascular disease
- 3638 experienced atrial fibrillation
- 1854 experienced heart failure
Multivariate adjusted models showed a significant risk between increased sedentary time and the risk of all four outcomes. More specifically, individuals in the top quartile [Q4] had a significantly higher risk of incident heart failure (HR = 1.45, P <0.05) and cardiovascular mortality (HR = 1.62, P <0.05) and moderate risk of heart attack (HR = 1.15, P <0.05) and atrial fibrillation (HR = 1.11, P <0.05). Furthermore, individuals whose sedentary time exceeded 10.6 hours/ day had significantly higher risk of death due to cardiovascular disease (HR = 1.54, P <0.05) and heart failure (HR = 1.40, P <0.05). Researchers also found that individuals who engaged in more than 10.6 hours of sedentary activity for 4 or more days were particularly at risk for all four outcomes. Further analysis also showed that every additional hour of sedentary time above 10.6 hours/day was significantly associated with an increased risk of heart failure and cardiovascular disease mortality (P <0.05). No interactions were observed below the 10.6 hours/day threshold for the risk of cardiovascular disease mortality and heart failure. Researchers also observed a significantly increased risk of myocardial infarction and atrial fibrillation among individuals whose sedentary time was above 10.6 hours/day (P < 0.05). Individuals who engaged in more than 150 minutes of moderate to vigorous physical activity per week had attenuated the risk of heart attack (HR = 1.00, P < 0.05) and atrial fibrillation (HR = 0.99, P <0.05). However, the risk of heart failure and cardiovascular mortality remained (P <0.05). Modeling also showed a significant interaction between moderate to vigorous physical activity and sedentary time for atrial fibrillation (P = 0.05) and heart failure (P = 0.04). Overall, reducing sedentary time was associated with a significantly reduced risk of cardiovascular disease mortality and heart failure. Moderate to vigorous activity more than 150 minutes per week somewhat mitigated the risk of sedentary behavior. However, individuals who already had excess risk of cardiovascular disease mortality and heart failure continued to show risk even after achieving moderate to vigorous physical activity for more than 150 minutes per week.
Results from this analysis showed that increased sedentary time is associated with a higher risk of cardiovascular disease mortality, atrial fibrillation, heart failure, and heart attack. Also, among individuals with sedentary time above 10.6 hours/ day, there was a significantly high risk of heart failure and cardiovascular disease mortality even after adjusting for physical activity. However, the association between myocardial infarction and atrial fibrillation was attenuated after adjustment for moderate to vigorous physical activity. Further studies will be needed to verify these results.
Source: Ajufo, Ezimamaka, Shinwan Kany, Joel T. Rämö, Timothy W. Churchill, J. Sawalla Guseh, Krishna G. Aragam, Patrick T. Ellinor, and Shaan Khurshid. “Accelerometer-measured sedentary behavior and risk of future cardiovascular disease.” Journal of the American College of Cardiology (2024).
© 2024 BY THE AMERICAN COLLEGE OF CARDIOLOGY FOUNDATION
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Posted January 7, 2025.
Chrystal Moulton BA, PMP, is a 2008 graduate of the University of Illinois at Chicago. She graduated with a bachelor’s in psychology with a focus on premedical studies and is a licensed project manager. She currently resides in Indianapolis, IN.
References:
- Lee IM, Shiroma EJ, Lobelo F, Puska P, Blair SN, Katzmarzyk PT. Effect of physical inactivity on major non-communicable diseases worldwide: an analysis of burden of disease and life expectancy. Lancet. Jul 21 2012;380(9838):219-29. doi:10.1016/s0140-6736(12)61031-9
- Wasfy MM, Lee IM. Examining the Dose-Response Relationship between Physical Activity and Health Outcomes. NEJM Evid. Dec 2022;1(12):EVIDra2200190. doi:10.1056/EVIDra2200190
- Matthews CE, Carlson SA, Saint-Maurice PF, et al. Sedentary Behavior in U.S. Adults: Fall 2019. Med Sci Sports Exerc. Dec 1 2021;53(12):2512-2519. doi:10.1249/mss.0000000000002751
- Lobelo F, Rohm Young D, Sallis R, et al. Routine Assessment and Promotion of Physical Activity in Healthcare Settings: A Scientific Statement From the American Heart Association. Circulation. May 1 2018;137(18):e495-e522. doi:10.1161/cir.0000000000000559
- Walmsley R, Chan S, Smith-Byrne K, et al. Reallocation of time between device-measured movement behaviours and risk of incident cardiovascular disease. Br J Sports Med. Sep 6 2021;56(18):1008-17. doi:10.1136/bjsports-2021-104050
- Ajufo E, Kany S, Rämö JT, et al. Accelerometer-Measured Sedentary Behavior and Risk of Future Cardiovascular Disease. J Am Coll Cardiol. Nov 11 2024;doi:10.1016/j.jacc.2024.10.065
