Compliance of First-Line Anti-Hypertensive Medications in Elderly Tibetan Semi-Nomadic Pastoralists

Abstract

The burden of hypertension and subsequent in Tibet is quite profound and disproportionate when compared to other Chinese populations. Thus, there has a recent impetus to focus on low-cost sustainable health interventions to ameliorate this tremendous burden. Factors of compliance of first-line low dose hypertensive medications are not known in semi-nomadic Tibetan herdsmen at high altitude.A retrospective analysis of a de-identified database for a single blinded equal allocation randomized control trial for a dietary reduced sodium salt substitute completed in 2009 using STATA 11.2 (STATA INC. College Station, TX) and logistic regression was performed. Patients were recruited from two townships at 4300 m altitude and northwest of Lhasa, the regional capital. Eligibility criteria included: age 40 years and older, with hypertension (≥ 140mmHg / ≥ 90 mmHg) , enrollment in salt substitute trial, and prescription of hypertensive medication. Primary outcome was compliance to medication at three and six months of follow-up. Factor variables included and adjusted for included: sex, age, blood pressure, township, class of medication, and trial arm assignment.The overall rate of non-compliance was 33.0% (38/115) after three months and 12.9% (28/217) after six months. After three months follow-up patients with Stage I and Stage II hypertension were at an adjusted odds ratio of 0.03(95%CI: 0.002-0.70) and 0.13(95%CI: 0.012-1.37) times lower odds of non-compliance when compared patients with only isolated systolic hypertension, (p=0.028 and 0.089, respectively). Furthermore, at six months of follow-up patients prescribed combination pharmacologic therapy had an adjusted odds ratios of 0.20 (95%CI: 0.05-0.81) times lower odds than those patients on diuretic only, p =0.023.