Fig. 7

Restricted spline curves for the associations between percentage change in BMI and all-cause mortality among overall (a), under/normal weight (b), overweight (c) and obesity (d) participants. The solid curve represents the multivariate-adjusted HRs calculated by restricted cubic splines with 3 knots at the 25th, 50th, and 75th of the percentage change in BMI; the solid dashed lines represent corresponding 95% confidence interval. The reference value (HR = 1) was set at percentage BMI change = 0. HRs were estimated by cox proportional hazard model adjusted of sex, age, race, education level, family annual income, marital status, physical activity level, family history of cancer in their first relatives, smoking status, screening arm, history of chronic disease (i.e., hypertension, heart attack, stroke, emphysema, diabetes, arthritis, and osteoporosis), and BMI value at study entry (continuous)