Changes in C-reactive protein during weight loss and the association with changes in anthropometric variables in men and women: LIFE Study

OBJECTIVE: To investigate whether sex differences exist in the pattern of change in C-reactive protein (CRP) levels during weight loss, and whether the associations between weight change and CRP change differ by the types of anthropometric variables. DESIGN: Longitudinal, prospective analysis of subjects participating in an intentional weight loss trial (the Lose It For Ever: LIFE Study) followed-up for 30 months. SUBJECTS: 212 healthy, obese men and women (age: 23–77y, BMI: 30–39kg/m(2)). MEASUREMENTS: Body mass index (BMI), waist and hip circumferences, and waist-to-hip ratio (WHR), CRP, and lifestyle variables repeatedly measured at baseline, 6, 12, 18, and 30-month follow-up. RESULTS: Weight change was J-shaped with a nadir at 12-months in both men and women (P for month2 <0.0001). CRP level was consistently higher in women than in men, but the differences were less prominent and were not statistically significant at 12-month and 18-month follow-up. CRP changes between any two consecutive visits were significantly associated with changes in BMI during the same period in women. However, the associations between CRP changes and changes in waist or hip circumference were not as consistent, especially between 18- to 30-month follow-up when CRP significantly increased. The associations in men were generally similar among the different anthropometric measures. The association between changes in BMI and CRP were stronger in men than in women. CONCLUSION: BMI change generally correlated well with CRP changes in both men and women in the course of follow-up. Significant sex-difference in CRP level at baseline diminished at 12- and 18-month follow-up, when both sexes had maintained the lost weight.