Metabolic syndrome and risk of death from cancers of the digestive system

We tested the hypothesis that risk of early mortality from cancers of the digestive system will be greater in men with, compared with men without, the metabolic syndrome (MetS). Participants were 33 230 men who were seen at the Cooper Clinic in Dallas, TX, and followed for 14.4 (SD = 7.0) years. Metabolic syndrome was defined as having at least 3 of the following risk factors: abdominal obesity, fasting hypertriglyceridemia, low high-density lipoprotein cholesterol, high blood pressure, or high fasting glucose level or diabetes. Metabolic syndrome was associated with higher mortality (hazard ratio [HR] = 1.90 [95% confidence interval = 1.42-2.55]), and there was a graded positive association for the addition of more syndrome components (P < .01). Adjustment for cardiorespiratory fitness attenuated the risk estimates by 20% to 30%, but they remained significant after this adjustment. Evaluation of the independent contribution of each of the syndrome components revealed that both abdominal obesity (HR = 1.89 [1.36-2.62]) and high glucose (HR = 1.38 [1.02-1.87]) were independently associated with cancer mortality. Our results support the hypothesis that metabolic syndrome is positively associated with mortality from cancers of the digestive system. Interventions that reduce abnormalities associated with the syndrome could reduce risk of premature death from these cancers.