This study aimed to evaluate the effect of an outpatient systemic hypertension program and associated factors with attending recommended follow-up visit. All visits were tracked in the program, 2011 to 2018. We examined patient characteristics by follow-up status and changes in systolic blood pressure (SBP) and the risk of hypertension in follow-up patients using a mixed-effects regression model. Among 310 patients with first visits, 113 patients returned for a follow-up visit. Patients who did not attend a follow-up were older and less likely to have a severe chronic condition or a family history of hypertension than followed-up patients. The risk of hypertension was significantly reduced by the number of follow-up visits (odds ratio = 0.53, 95% confidence interval = 0.31-0.92). Adolescent SBP and body mass index percentiles decreased with more follow-up visits. As the risk of hypertension is significantly reduced with follow-up visits, additional effort should be made to improve the likelihood of follow-up attendance.