BMI and Cardiovascular Risks: Insights from 1.8 Million Participants in 97 Cohorts

The article is titled “Metabolic mediators of the effects of body-mass index, overweight, and obesity on coronary heart disease and stroke: a pooled analysis of 97 prospective cohorts with 1·8 million participants.” It is by Goodarz Danaei and Majid Ezzati from Harvard University along with a large research team.

The study analyzed data on over 1.8 million people across 97 different research projects. It looked at how higher BMI and obesity connect to heart disease and stroke risk. It also examined if other metabolic factors like blood pressure, cholesterol and blood sugar that often go along with obesity are responsible.

Main Findings:

46% of the increased risk of heart disease from higher BMI is mediated by metabolic factors

76% of the increased risk of stroke from higher BMI is mediated

Blood pressure has the biggest impact, accounting for 31% of heart disease and 65% of stroke risk

Overweight and obese adults have higher chances of developing heart disease and stroke versus those with normal weight. But a substantial proportion of this excess risk disappears if their blood pressure, cholesterol and blood glucose are at normal levels.

Conclusion

The study shows managing related metabolic factors could prevent around half of heart disease and three-quarters of stroke associated with overweight/obesity. Still, maintaining a healthy BMI through diet and lifestyle remains important for full protection.

Global Burden of Metabolic Risk Factors for Chronic Diseases Collaboration (BMI Mediated Effects); Lu, Y., Hajifathalian, K., Ezzati, M., Woodward, M., Rimm, E. B., Danaei, G., & Collaborators. (2014). "Metabolic mediators of the effects of body-mass index, overweight, and obesity on coronary heart disease and stroke: a pooled analysis of 97 prospective cohorts with 1·8 million participants." The Lancet, 383(9921), 970-983. doi: 10.1016/S0140-6736(13)61836-X. PMID: 24269108. PMCID: PMC3959199. Available at: https://pubmed.ncbi.nlm.nih.gov/24269108/