Prevalence of uncontrolled hypertension among the Palestine refugee population (>40 years old) from 2008 to 2012. The trend (change in prevalence of hypertension) was calculated using simple linear regression model. T-tests for change in prevalence of any and uncontrolled hypertension across years were not statistically significant [P = 0.396 and P = 0.130, respectively]. The average increase in the prevalence of any hypertension per year was 0.29%. The average decrease in the percentage of hypertensive patients with uncontrolled high blood pressure per year was 2.87%.