Aim: To quantitatively examine the impacts of an easy-to-measure parameter - weight gain - on metabolic syndrome development among middle-aged adults.
Methods: We conducted a five-year interval observational study. A total of 1384 middle-aged adults not meeting metabolic syndrome (MetS) criteria at the initial screening were included in our analysis. Baseline data such as MetS-components and lifestyle factors were collected in 2002. Body weight and MetS-components were measured in both 2002 and 2007. Participants were classified according to proximal quartiles of weight gain (WG) in percentages (%WG ≤ 1%, 1% < %WG ≤ 5%, 5% < %WG ≤ 10% and %WG > 10%, defined as: control, mild-WG, moderate-WG and severe-WG groups, respectively) at the end of the follow-up. Multivariate models were used to assess the association between MetS outcome and excessive WG in the total population, as well as in both genders.
Results: In total, 175 (12.6%) participants fulfilled MetS criteria within five years. In comparison to the control group, mild-WG adults had an insignificant risk for MetS development while adults having moderate-WG had a 3.0-fold increased risk for progression to MetS [95% confidence interval (CI), 1.8-5.1], and this risk was increased 5.4-fold (95% CI, 3.0-9.7) in subjects having severe-WG. For females having moderate- and severe-WG, the risk for developing MetS was 3.6 (95% CI, 1.03-12.4) and 5.5 (95% CI, 1.4-21.4), respectively. For males having moderate- and severe-WG, the odds ratio for MetS outcome was respectively 3.0 (95% CI, 1.6-5.5) and 5.2 (95% CI, 2.6-10.2).
Conclusion: For early-middle-aged healthy adults with a five-year weight gain over 5%, the severity of weight gain is related to the risk for developing metabolic syndrome.
Keywords: Excess weight gain; Follow-up; Metabolic syndrome; Middle-aged adults; Worker population.