Changes of systemic microinflammation after weight loss and regain - a five-year follow up study.

Introduction: The aim of this study was to evaluate the influence of body mass changes on plasma concentrations of proinflammatory cytokines in obese women after the initially obtained weight reduction in a five-year follow-up period.

Material And Methods: Thirty out of 42 women with simple obesity (age 41.8 ± 11.9 years; BMI 36.5 ± 4.6 kg/m2) who achieved a greater than 5% weight loss at the end of a three-month weight loss programme were re-examined after five years. In addition to anthropometric and body composition measurements, plasma concentrations of TNF-alpha, sTNFRs and IL-6 were determined.

Results: The mean weight loss after the three-month weight loss programme was 7.9 ± 4.4 kg. After five years, body mass was still lower than initially in 14 women, while in 16 it was higher (the so-called 'yo-yo effect'). A significant decrease of plasma TNF-alpha and IL-6 and increase of sTNFR1 and sTNFR2 levels obtained after weight loss therapy were maintained after five years, including in the subgroup with the yo-yo effect. During the follow-up period, the increase of body fat mass was similar in the subgroup that maintained reduced weight (+4.4 ± 10.7 kg) and in the subgroup with the yo-yo effect (+4.1 ± 7.1 kg), while a significant difference was found in changes of body free fat mass (-7.1 ± 7.1 v. -0.7 ± 4.5 kg, respectively).

Conclusions: The yo-yo effect has a modest influence on systemic microinflammation and seems not to abolish the benefit achieved via a weight loss programme. This may suggest that the persistence of changes in lifestyle implemented during the programme such as regular physical activity and diet composition may have a significant impact on the level of systemic microinflammation in the obese. (Endokrynol Pol 2012; 63 (6): 432-438).