Studies of sex differences in the effect of abdominal obesity on stroke risk have had conflicting results (Table 11). The impact of obesity on poststroke outcomes remains unclear. One retrospective analysis of cross-sectional and pro- spective data from a nationally representative survey of the US adult population followed up from survey participation in 1988 to 1994 through mortality assessment in 2000 revealed that the overall risk for all-cause mortality among stroke sur- vivors increased per 1 kg/m2 of higher BMI (P=0.030), but an interaction between age and BMI (P=0.009) revealed that the association of higher BMI with mortality risk was strongest in younger individuals and declined linearly with On the other hand, a post hoc analysis of the Telemedical Project for Integrative Stroke Care (TEMPiS) revealed that mortality risk was lower in overweight patients (HR, 0.69; 95% CI, 0.56 0.86) and lowest in obese (HR, 0.50; 0.66) patients compared with those with normal BMI.316 It is unclear whether obesity has a differential impact on stroke outcomes in women compared with men.317 Metabolic Syndrome Metabolic syndrome, a combination of cardiometabolic risk factors that tend to cluster together (insulin resistance, abdominal adiposity, dyslipidemia, and hypertension) affects approximately one third of the US adult population.318 Analysis of data from NHANES 2003 to 2006 revealed that 36.1% of men and 32.4% of women in the United States had metabolic Numerous studies have shown an association between metabolic syndrome and stroke in both men and women303,310,311,314,319 326 (Table 12). The exact mecha- nism whereby metabolic syndrome affects cardiovascular risk is unknown; it is thought that components of the syndrome synergistically increase vascular risk through mechanisms that include insulin resistance, hypercoagulability, endothelial dysfunction, and inflammation. 