Associations of metabolic syndrome and C-reactive protein with mortality from total cancer, obesity-linked cancers and breast cancer among women in NHANES III.

Although metabolic syndrome (MetS) is a prognostic factor for cancer occurrence, the association of MetS and cancer mortality remains unclear. The purpose of this study was to evaluate whether MetS, components of MetS and C-reactive protein (CRP) are associated with cancer mortality in women. A total of 400 cancer deaths, with 140 deaths from obesity-linked-cancers (OLCas), [breast (BCa), colorectal, pancreatic and endometrial], linked through the National Death Index, were identified from 10,104 eligible subjects aged ≥18 years. Cox proportional hazards regression was used to estimate multivariable-adjusted hazard ratios (HR) for cancer mortality. MetS was associated with increased deaths for total cancer [HR = 1.33, 95% confidence interval (CI) 1.04-1.70] and BCa [HR = 2.1, 95% CI, 1.09-4.11]. The risk of total cancer [HR = 1.7, 95% CI, 1.12-2.68], OLCas [HR = 2.1, 95% CI, 1.00-4.37] and BCa [HR = 3.8, 95% CI, 1.34-10.91] mortality was highest for women with all MetS components abnormal, compared to those without MetS. Linear associations of blood-pressure [HR = 2.5, 1.02-6.12, Quartile (Q) 4 vs Q1, p trend = 0.004] and blood-glucose [HR = 2.2, 1.04-4.60, Q4 vs. Q1, p trend = 0.04] with total-OLCas mortality were observed. A threefold increased risk of BCa mortality was observed for women with enlarged waist circumference, ≥100.9 cm, [HR = 3.5, 1.14-10.51, p trend = 0.008] and in those with increased blood glucose, ≥101 mg/dL, [HR = 3.2, 1.11-9.20, p trend = 0.03] compared to those in Q1. None of the components of MetS were associated with total-cancer mortality. CRP was not associated with cancer mortality. In conclusion, MetS is associated with total-cancer and breast-cancer mortality, with waist circumference, blood pressure and blood glucose as independent predictors of OLCas and BCa mortality.