Background:Treatment resistant hypertension(TRH) is detrimental risk of cardiovascular and premature deaths. Globally, the prevalence of resistant hypertension is inclining from time to time and it is yet to be determined in Ethiopia.

Objective: To assess the prevalence of apparent TRH and its predictors among ambulatory hypertensive patients on follow up in hypertension clinic of Mekelle Hospital, Northern Ethiopia.

Method: A hospital based cross sectional study was conducted from Nov 25, 2018 to July 20, 2019, among 338 adult ambulatory hypertensive patients on follow up in Mekelle Hospital hypertension clinic. Hypertensive patient aged ≥18 years who were on regular follow up and taking antihypertensive medications for at least 6 months were included in the study. A simple random sampling technique was used to recruit the study patients.

Results: A total of 338 adult ambulatory hypertensive patients were analysed. More than half, 182 (53.8%) patients were females and the average age of the patients was 58.9 ±11.5. Three hundred thirty-three (98.5%) patients had no family history of hypertension. Majority, 66.8% of the patients were on monotherapy. The prevalence of apparent TRH was calculated to be 8.6% [Confidence Interval = 0.056-0.116]. Patients with Body Mass Index(BMI) greater than 30[Adjusted Odds Ratio(AOR) = 12.1, 95%CI:2.00-73.19, p = 0.007] and longer duration of hypertension were the predictors of resistant hypertension.

Conclusion: Even if escalation of antihypertensive medications was not aggressive, apparent TRH was common in the study setting. Obesity (BMI greater than 30) and longer duration of hypertension since diagnosis were the predictors of TRH. Meticulous emphasis should be placed on to detect the prevalence of true hypertension resistance and future studies should discover the impact of aggressive antihypertensive medications scale up on the risks of TRH.