Relation of Change of Body Mass Index to Long-Term Mortality After Cardiac Catheterization

Abstract

Body-mass index (BMI) is a risk marker and therapeutic target in cardiovascular prevention. The effect of changes in BMI on mortality in patients with cardiovascular diseases has not been completely delineated. We aimed to assess the association between percent change in BMI, as measured 3-years after cardiac catheterization, and long-term mortality. Patients who underwent cardiac catheterization (n = 11,220; mean age 63 ± 10 years) were categorized according to BMI groups (normal-weight, 18.50 to 24.99 kg/m2; overweight, 25.00 to 29.99 kg/m2; obesity, ≥30 kg/m2). Follow-up BMI was considered the level measured closest to the timepoint of 3 years post catheterization. Percent change in BMI was calculated and its association with long-term all-cause mortality was investigated. Change in BMI of ±5% was observed in 46% of the patients, a decrease >5% in 15.5%, and an increase of >5% of BMI in 38.5%. Compared with those with the lowest change in BMI (±5%), the adjusted hazard ratios for mortality were 1.45 (95% confidence interval [CI], 1.27 to 1.65), and 1.69 (1.46 to 1.95) in patients with 5% to 10% and >10% decrease in BMI, respectively, and 1.05 (0.94 to 1.17), 1.15 (1.03 to 1.28), and 1.40 (1.19 to 1.64) in patients with 5% to 10%, 10% to 20% and >20% increase in BMI, respectively. The pattern was similar in normal-weight, overweight, and obese subgroups at baseline. However, the magnitude of the association with decrease BMI was more pronounced in normal-weight patients (P-for-interaction 0.031). In conclusion, the association of percent changes in BMI after cardiac catheterization and all-cause mortality had a reversed J-shaped pattern, with both weight loss and weight gain being associated with increased risk. A decrease in BMI was related to higher mortality rates than was an increase in BMI for a comparable degree of percent change.