Dr. Marinac and her team identified a total of 205 men from the HPFS cohort and 370 women (325 NHS, 45 WHS) with confirmed diagnoses of MM. The BMIs of those participants ranged from 23.8-25.8 kg/m2 at baseline and from 21.3-23.0 kg/m2 in young adulthood. Across all cohorts, each 5 kg/m2 increase in cumulative average adult BMI significantly increased the risk of MM by 17% (hazard ratio, 1.17; 95% confidence interval, 1.05-1.29).
In addition, the MM risk rose almost 30% for every 5 kg/m2 increase in young adult BMI (HR, 1.28; 95% CI, 1.12-1.47). Increased risk was not strictly related to changes in BMI but to incremental weight gain since young adulthood.
(pooled HR, 1.04; 95% CI, 1.00-1.08; P = 0.03).The study confirmed correlations between weight gain and increased MM risk, however, it also had certain limitations. For example, much of the data concerning weight, height, and physical activity were all self-reported. Another limitation is the sociodemographic heterogeneity of the study population.
Despite those limitations, Dr. Marinac emphasized that the study results add to evidence concerning weight gain and MM risk.