Erectile dysfunction (ED) is a prevalent condition and a predictor of future cardiovascular events. Screening and treatment of ED may improve management of cardiovascular risk factors. We evaluated the potential beneficial effect of newly treating ED on the management of hypertension in men in the New England Veteran Affairs Healthcare System. We conducted a retrospective cohort study using medical record data to identify patients diagnosed with and treated at any time for hypertension who received a prescription for a phosphodiesterase type 5 inhibitor (PDE5i) before February 1, 2003. Fifty percent of 6,768 men (mean +/- SD 61.6 +/- 9.9 years of age) had a systolic blood pressure (BP) > or =140 mm Hg before PDE5i administration. Overall, there was a decrease in systolic BP by 1.43 mm Hg (95% confidence interval -1.69 to -1.18) after initiation of PDE5i. The decrease in systolic BP was most pronounced in men with a systolic BP > or =160 mm Hg at baseline (-17.8 mm Hg, 95% confidence interval -18.8 to -16.8). After initiating therapy with PDE5i, patients were more likely to start an antihypertensive medication (17.3%) versus stop therapy (2.3%) and add additional antihypertensive medication to their existing therapy (42.2%) versus decrease the number of medications (17.3%). Surveillance also increased with total number of systolic BP measurements increasing by 42%. In conclusion, men with high systolic BP who initiated ED therapy had improvements in systolic BP control that may be related to clinically relevant behaviors, such as more aggressive monitoring and treatment with antihypertensive medications.