OBJECTIVES: The cardiovascular consequences of the metabolic syndrome and its component risk factors (i.e., abdominal obesity, low HDL cholesterol or elevated triglyercides, hypertension, elevated blood glucose) have been documented in the elderly. To date, little is known about how the metabolic syndrome and its components translate into long-term medical costs. METHODS: We used clinical data and matching, longitudinal Medicare claims from 3,789 individuals aged 65 years and older in the Cardiovascular Health Study followed up to 10 years. The metabolic syndrome was defined according to the National Cholesterol Education Program's Third Adult Treatment Panel Report (NCEP-ATP III) criteria. W calculated costs by summing Medicare payment amounts for each participant, and discounted costs at 3% annually. Log-linear regression models were used to assess the independent contributions of the metabolic syndrome and its component risk factors to 10-year medical costs among. RESULTS: As defined by the NCEP ATP III criteria, the metabolic syndrome was present in 47% of the sample. Total per patient costs to Medicare were 20% higher among those with the metabolic syndrome ($40,827 vs. $32,962, p<0.001). Controlling for age, gender, race and other covariates, abdominal obesity, low HDL cholesterol, and elevated blood pressure were associated with 15% (95% confidence interval [CI] 4.3%-26.7%), 16% (CI: 1.1% -31.8%), and 20% (CI 10.1%-31.7%) higher total costs, respectively. When added to the model, the metabolic syndrome composite variable did not contribute significantly (p=0.32). CONCLUSION: Abdominal obesity, low HDL cholesterol, and hypertension, but not the metabolic syndrome, are important predictors of long-term costs in the Medicare population. The combined effects of abdominal obesity, low HDL cholesterol, and elevated blood pressure are associated with 50% higher Medicare costs.