Effect of a Community Health Worker-Led Multicomponent Intervention on Blood Pressure Control in Low-Income Patients in Argentina: A Randomized Clinical Trial.

Importance: Despite extensive knowledge of hypertension treatment, the prevalence of uncontrolled hypertension is high and increasing in low- and middle-income countries. Objective: To test whether a community health worker-led multicomponent intervention would improve blood pressure (BP) control among low-income patients with hypertension. Design, Setting, and Participants: A cluster randomized trial was conducted in 18 centers for primary health care within a national public system providing free medications and health care to uninsured patients in Argentina. A total of 1432 low-income adult patients with uncontrolled hypertension were recruited between June 2013 and April 2015 and followed up to October 2016. Interventions: Nine centers (743 patients) were randomized to the multicomponent intervention, which included a community health worker-led home intervention (health coaching, home BP monitoring, and BP audit and feedback), a physician intervention, and a text-messaging intervention over 18 months. Nine centers (689 patients) were randomized to usual care. Main Outcomes and Measures: The coprimary outcomes were the differences in systolic and diastolic BP changes from baseline to the end of follow-up of patients with hypertension. Secondary outcomes included the proportion of patients with controlled hypertension (BP <140/90 mm Hg). Three BP measurements were obtained at each of 2 baseline and 2 termination visits using a standard protocol, the means of which were used for analyses. Results: Of 1432 participants (mean age, 55.8 years [SD, 13.3]; 772 women [53.0%]), 1357 (94.8%) completed the trial. Baseline mean systolic BP was 151.7 mm Hg for the intervention group and 149.8 mm Hg for the usual care group; the mean diastolic BP was 92.2 mm Hg for the intervention group and 90.1 mm Hg for the usual care group. Systolic BP reduction from baseline to month 18 was 19.3 mm Hg (95% CI, 17.9-20.8 mm Hg) for the intervention group and 12.7 mm Hg (95% CI, 11.3-14.2 mm Hg) for the usual care group; the difference in the reduction was 6.6 mm Hg (95% CI, 4.6-8.6; P < .001). Diastolic BP decreased by 12.2 mm Hg (95% CI, 11.2-13.2 mm Hg) in the intervention group and 6.9 mm Hg (95% CI, 5.9-7.8 mm Hg) in the control group; the difference in the reduction was 5.4 mm Hg (95% CI, 4.0-6.8 mm Hg; P < .001). The proportion of patients with controlled hypertension increased from 17.0% at baseline to 72.9% at 18 months in the intervention group and from 17.6% to 52.2% in the usual care group; the difference in the increase was 20.6% (95% CI, 15.4%-25.9%; P < .001). No adverse events were reported. Conclusions and Relevance: Low-income patients in Argentina with uncontrolled hypertension who participated in a community health worker-led multicomponent intervention experienced a greater decrease in systolic and diastolic BP than did patients who received usual care over 18 months. Further research is needed to assess generalizability and cost-effectiveness of this intervention and to understand which components may have contributed most to the outcome. Trial Registration: clinicaltrials.gov Identifier: NCT01834131.

Sodium sensitivity of blood pressure in Chinese populations.

Hypertension is an enormous public-health challenge in the world due to its high prevalence and consequent increased cardiovascular disease morbidity and mortality. Observational epidemiologic studies and clinical trials have demonstrated a causal relationship between sodium intake and elevated blood pressure (BP). However, BP changes in response to sodium intervention vary among individuals-a trait called sodium sensitivity. This paper aims to review the recent advances in sodium-sensitivity research in Chinese and other populations. Older age, female gender, and black race are associated with high sodium sensitivity. Both genetic and environmental factors influence BP sodium sensitivity. Physical activity and dietary potassium intake are associated with reduced sodium sensitivity while obesity, metabolic syndrome, and elevated BP are associated with increased sodium sensitivity. Familial studies have documented a moderate heritability of sodium sensitivity. Candidate gene association studies, genome-wide association studies, whole-exome, and whole-genome sequencing studies have been conducted to elucidate the genomic mechanisms of sodium sensitivity. The Genetic Epidemiology Network of Salt Sensitivity (GenSalt) study, the largest family-based feeding study to date, was conducted among 1906 Han Chinese in rural northern China. This study showed that ~32.4% of Chinese adults were sodium sensitive. Additionally, several genetic variants were found to be associated with sodium sensitivity. Findings from the GenSalt Study and others indicate that sodium sensitivity is a reproducible trait and both lifestyle factors and genetic variants play a role in this complex trait. Discovering biomarkers and underlying mechanisms for sodium sensitivity will help to develop individualized intervention strategies for hypertension.

Comprehensive approach for hypertension control in low-income populations: rationale and study design for the hypertension control program in Argentina.

Although the efficacy and effectiveness of lifestyle modifications and antihypertensive pharmaceutical treatment for the prevention and control of hypertension and concomitant cardiovascular disease have been demonstrated in randomized controlled trials, this scientific knowledge has not been fully applied in the general population, especially in low-income communities. This article summarizes interventions to improve hypertension management and describes the rationale and study design for a cluster randomized trial testing whether a comprehensive intervention program within a national public primary care system will improve hypertension control among uninsured hypertensive men and women and their families. We will recruit 1,890 adults from 18 clinics within a public primary care network in Argentina. Clinic patients with uncontrolled hypertension, their spouses and hypertensive family members will be enrolled. The comprehensive intervention program targets the primary care system through health care provider education, a home-based intervention among patients and their families (home delivery of antihypertensive medication, self-monitoring of blood pressure [BP], health education for medication adherence and lifestyle modification) conducted by community health workers and a mobile health intervention. The primary outcome is net change in systolic BP from baseline to month 18 between intervention and control groups among hypertensive study participants. The secondary outcomes are net change in diastolic BP, BP control and cost-effectiveness of the intervention. This study will generate urgently needed data on effective, practical and sustainable intervention programs aimed at controlling hypertension and concomitant cardiovascular disease in underserved populations in low- and middle-income countries.