Short- and long-term mortality in a prevalent cohort of morbidly obese patients in Italy

Background Morbid obesity has been associated with increased mortality. Aim of the study We evaluated the risk of short- (2 years) and long-term (10 years) mortality in two consecutive series of Italian morbidly obese patients hospitalized in a Metabolic Unit. Methods The vital status of 569 patients (435 females and 134 males, BMI 44.4 kg/m(2), age 46.1 years), first admitted for clinical treatment in two separate periods (1988 and 1996), was ascertained in 1999. Results Twenty-seven deaths were identified and compared with expected deaths according to mortality rates in the Italian population, to estimate the standardized mortality ratio (SMR). In the first two years after admission only 3 deaths were observed and the SMR tended to be reduced (SMR = 0.5, 95% CI 0.1-1.5). In contrast, the long-term follow-up showed a significantly elevated risk of death (SMR = 1.6, 95% CI 1.1-2.4). Conclusions The follow-up of this Italian prevalent cohort confirm that morbid obesity is associated with increased mortality. The observed SMR might have been attenuated by inclusion in our study of subjects with relatively good health conditions, who are possibly more representative of the general obese population than subjects affected by important obesity-related complications, observed in other studies. The excess risk was not evident in the first two years after clinical treatment.