Hossein Mozafar Saadati1, Siamak Sabour1, Mohammad Ali Mansournia2, Yadollah Mehrabi1, Seyed Saeed Hashemi Nazari3. 1. Departamento de Epidemiologia, Faculdade de Saúde Pública e Segurança, Shahid Beheshti University of Medical Sciences, Tehran - Irã. 2. Departamento de Epidemiologia e Bioestatística, Faculdade de Saúde Pública, Tehran University of Medical Sciences, Tehran - Irã. 3. Centro de Pesquisa de Prevenção de Doenças Cardiovasculares, Faculdade de Saúde Pública e Segurança, Shahid Beheshti University of Medical Sciences, Tehran - Irã.
Abstract
BACKGROUND: Body mass index (BMI) is the most commonly used index to categorize a person as obese or non-obese, which is subject to important limitations. OBJECTIVE: To evaluate the direct effect of BMI on cardiovascular outcomes among participants without central obesity. METHODS: This analysis included 14,983 males and females aged 45-75 years from the Atherosclerosis Risk in Communities Study (ARIC). BMI was measured as general obesity, and waist circumference (WC), waist-to-hip ratio (WHR) and hip circumference as central obesity. Targeted maximum likelihood estimation (TMLE) was used to estimate the total effects (TEs) and the controlled direct effects (CDEs). The proportion of TE that would be eliminated if all participants were non-obese regarding central obesity was computed using the proportion eliminated (PE) index. P <0.05 was considered statistically significant. Analyses were performed in the TMLE R package. RESULTS: The risk of cardiovascular outcomes attributed to BMI was significantly reversed by eliminating WHR obesity (p<0.001). The proportion eliminated of BMI effects was more tangible for non-obese participants regarding WC (PE=127%; 95%CI (126,128)) and WHR (PE=97%; 95%CI (96,98)) for coronary heart disease (CHD), and WHR (PE=92%; 95%CI (91,94)) for stroke, respectively. With respect to sex, the proportion eliminated of BMI effects was more tangible for non-obese participants regarding WHR (PE=428%; 95%CI (408,439)) for CHD in males, and WC (PE=99%; 95%CI (89,111)) for stroke in females, respectively. CONCLUSION: These results indicate different potential effects of eliminating central obesity on the association between BMI and cardiovascular outcomes for males and females. (Arq Bras Cardiol. 2021; 116(5):879-886).
BACKGROUND: Body mass index (BMI) is the most commonly used index to categorize a person as obese or non-obese, which is subject to important limitations. OBJECTIVE: To evaluate the direct effect of BMI on cardiovascular outcomes among participants without central obesity. METHODS: This analysis included 14,983 males and females aged 45-75 years from the Atherosclerosis Risk in Communities Study (ARIC). BMI was measured as general obesity, and waist circumference (WC), waist-to-hip ratio (WHR) and hip circumference as central obesity. Targeted maximum likelihood estimation (TMLE) was used to estimate the total effects (TEs) and the controlled direct effects (CDEs). The proportion of TE that would be eliminated if all participants were non-obese regarding central obesity was computed using the proportion eliminated (PE) index. P <0.05 was considered statistically significant. Analyses were performed in the TMLE R package. RESULTS: The risk of cardiovascular outcomes attributed to BMI was significantly reversed by eliminating WHR obesity (p<0.001). The proportion eliminated of BMI effects was more tangible for non-obeseparticipants regarding WC (PE=127%; 95%CI (126,128)) and WHR (PE=97%; 95%CI (96,98)) for coronary heart disease (CHD), and WHR (PE=92%; 95%CI (91,94)) for stroke, respectively. With respect to sex, the proportion eliminated of BMI effects was more tangible for non-obeseparticipants regarding WHR (PE=428%; 95%CI (408,439)) for CHD in males, and WC (PE=99%; 95%CI (89,111)) for stroke in females, respectively. CONCLUSION: These results indicate different potential effects of eliminating central obesity on the association between BMI and cardiovascular outcomes for males and females. (Arq Bras Cardiol. 2021; 116(5):879-886).