Parameters of inflammation in morbid obesity: lack of effect of moderate weight loss.

BACKGROUND

Obesity has been associated with a chronic activation of the acute-phase response. The aims of our study were to investigate whether levels of inflammatory cytokines are higher in obese patients, to evaluate their relationship with metabolic syndrome, and to analyze the effect of moderate weight loss upon their levels.

METHODS

Sixty-seven severe or morbid obese patients were compared with 67 controls. Patients were submitted to a 4-week very low calorie diet followed by a low calorie diet for 2 months. Exclusion criteria were organic disease, ischemic heart disease or stroke, diabetes mellitus, hyperlipidemia, and hypertension. An evaluation was performed before and after the diet, in which fibrinogen, blood count, high-sensitive C-reactive protein (CRP), interleukin 6 (IL-6), and tumoral necrosis factor alpha (TNF-alpha) were measured. The Student t test was employed to compare differences between the groups and Pearson correlation coefficients were calculated.

RESULTS

Obese patients showed higher levels of CRP (P < 0.001), IL-6 (P < 0.001), TNF-alpha (P < 0.001), leukocyte (P = 0.001), and neutrophil count (P < 0.001) than controls. In obese patients, inflammatory parameters were significantly correlated with anthropometric parameters and did not differ between obese subjects with or without metabolic syndrome. Moderate weight loss (excess weight loss 19.6%) was achieved through dieting, but no change was observed in any inflammatory parameter.

CONCLUSIONS

Obesity is associated to a chronic inflammatory state that seems to be due to an increased secretion of cytokines, and this state is not related to the presence of metabolic syndrome. Moderate weight loss does not ameliorate this inflammatory state in the short term.