Obesity but not overweight increases the incidence and mortality of leukemia in adults: a meta-analysis of prospective cohort studies.

The main objectives of the present meta-analysis of prospective cohort studies were to evaluate the role of obesity on the incidence and mortality of leukemia in adults. Obesity was associated with a relative risk (RR) of 1.26 (95% CI 1.17-1.37; p < 0.001) for leukemia incidence and 1.29 (95% CI 1.11-1.49; p = 0.001) for mortality. Obesity was also associated with an increased incidence of acute myeloid leukemia (RR 1.53, 95% CI 1.26-1.85; p<0.001), chronic lymphocytic leukemia (RR 1.17, 95% CI 1.08-1.27; p < 0.001), chronic myeloid leukemia (RR 1.16, 95% CI 1.04-1.30; p = 0.007) and acute lymphoblastic leukemia (RR 1.62, 95% CI 1.12-2.32; p = 0.009). The risk of incidence and mortality of leukemia in adults was consistently higher in obese men.