Herbal medicines and blood pressure control among hypertensive individuals across two of trinidad's regional health facilities.

Background: Self-medication with herbal medicine (HM) to manage hypertension is an expanding trend worldwide. There is very little evidence to substantiate the motives for use in the control of blood pressure (BP). This study aims to ascertain the relationship between HM and antihypertensive treatment to manage hypertension across two regional health facilities in Trinidad.

Methods: This cross-sectional investigation surveyed hypertensive patients aged 35-64 from the North-Central and Eastern Regional Health facilities across Trinidad. Consent was obtained from 139 participants through convenience sampling. Data collection was obtained using a questionnaire designed and developed by the research team, included a self-reporting questions and patient medical records sections. Data was analysed using Chi-square and Mann-Whitney U tests for non-normally distributed variables, with statistical significance set at a 95% confidence interval.

Results: HM-users were either hypertensive stage 1 or 2 with no significant correlation between BMI and hypertensive stage (p-value = -0.053, p-value = 0.537). Garlic (Allium sativum L) (57%), most used as a tea, was taken daily 'to control BP'. The current systolic and diastolic blood pressures were not significantly different between HM-users and non-users. Among herbal medicine users, 15.7% achieved blood pressure control compared to 30.4% for non-users. Patients using herbal medicine (84.3%) were more likely to have uncontrolled blood pressure (p-value < 0.05), supported by a negative correlation (phi = -0.175) and an odds ratio (95% CI) of 0.426 (0.187-0.969). Patient non-concordance to conventional medication was found to be higher among HM-users identified by the negative association among patients with uncontrolled BP. However, there was no statistically significant difference in non-concordance between HM users (40%) and non-users (29.6%). Antihypertensives prescribed included calcium channel blockers (70.1%), ACE inhibitors (46.3%), and angiotensin-II receptor blockers (40.6%). The most used herb, A. sativum, was preferred for BP control, however, this study showed no significant changes in BP compared to non-users.

Conclusion: Patient medication concordance is imperative. Herb-drug interactions may be associated with the higher prevalence of patients at hypertensive stages 1 and 2 that are uncontrolled in this study.