BACKGROUND Clinical trials have provided convincing evidence that blood pressure (BP) lowering treatment reduces the risk of cardiovascular disease (CVD) and total mortality. The objective of this study was to examine the association of hypertension treatment, control, and BP indexes with all-cause and cardiovascular mortality among US adults with hypertension. METHODS Persons aged > or =18 years from the Third National Health and Nutrition Examination Survey (NHANES III) were identified as hypertensives based on a BP > or =140/90 mm Hg or current treatment for hypertension. Vital status in 2006 was ascertained by passive follow-up using the National Death Index. Cox regression models were used to assess correlates of survival. RESULTS At baseline, 52% of hypertensive adults reported currently taking prescription medicine for high BP and 38% of treated persons had BP controlled. Compared to treated controlled hypertensives, treated uncontrolled hypertensives had a 1.57-fold (95% confidence interval (CI) 1.28-1.91) and 1.74-fold (95% CI 1.36-2.22) risk of all-cause and cardiovascular mortality; untreated hypertensives had a 1.34-fold (95% CI 1.12-1.62) and 1.37-fold (95% CI 1.04-1.81) risk of all-cause and cardiovascular mortality, respectively. The association persisted after further excluding persons with pre-existing hypertension comorbidities. Mortality risk was linearly increased with systolic BP (SBP), pulse pressure (PP), and mean arterial pressure (MBP), whereas diastolic BP (DBP) was not a significant predictor of cardiovascular mortality overall. No significant associations were observed between drug classes and mortality risk. CONCLUSIONS This study indicates that uncontrolled and untreated hypertension was associated with increased risk of total and cardiovascular mortality among the general hypertensive population.