A Cluster Randomized Trial of A Village Doctor-Led Intervention on Blood Pressure Control: - PowerPoint Presentation

1. A Cluster Randomized Trial of A Village Doctor-Led Intervention on Blood Pressure Control: China Rural Hypertension Control Project Yingxian Sun, Zhao Li, Xiaofan Guo, Ying Zhou, Nanxiang Ouyang, Liying Xing, Guozhe Sun, Jianjun Mu, Daowen Wang, Chunxia Zhao, Jun Wang, Ning Ye, Liqiang Zheng, Shuang Chen, Ye Chang, Ruihai Yang, Jiang He, for CRHCP Study GroupAll authors have no conflicts of interest to declare.

2. BackgroundHypertension is the leading global preventable risk factor for CVD and premature death. Approximately 75% of individuals with hypertension live in low- and middle-income countries.The prevalence of hypertension is high and increasing in China. In the most recent national survey in 2014, 27.8% or 292 million Chinese adults had hypertension (BP ≥140/90 mm Hg).The proportion of patients with controlled BP in China is low. Only 5.5% of hypertensive patients had BP controlled (<140/90 mmHg) in rural China in 2014.Village doctors (formerly known as barefoot doctors) have traditionally provided basic primary healthcare in rural China. With appropriate training, they could play an important role in hypertension control in rural China.

3. ObjectivesTo test the effectiveness of a village doctor-led multifaceted intervention compared to usual care on BP control over 18 months among rural residents with hypertension in China. To test the feasibility of implementing a more stringent BP treatment goal (<130/80 mmHg) than that in the China Hypertension Guidelines (<140/90 mmHg).

4. 163 villages randomized to usual care163 villages randomized to intervention326 villages selected from 3 provinces in China23780 patients assessed for eligibility22960 patients assessed for eligibility6373 excluded6372 excluded17407 patients enrolled to intervention16588 patients enrolled to usual care 15454 patients completed 18-month follow-up17407 patients included in data analysis1953 patients lost to follow-up2064 patients lost to follow-up14524 patients completed 18-month follow-up16588 patients included in data analysis326 villages randomizedEnrollment, Randomization, and Follow-up

5. Study ParticipantsMen and women aged ≥40 years with a mean untreated SBP ≥140 mmHg and/or DBP ≥90 mmHg or mean treated SBP ≥130 mmHg and/or DBP ≥80 mmHg from six measures on two different days were eligible for this trial.Patients with a history of CVD, diabetes, or CKD and mean SBP ≥130 mmHg and/or DBP ≥80 mmHg were also eligible.In addition, patients were required to be enrolled in the China New Rural Cooperative Medical Scheme, which covers 99% of rural residents for basic healthcare services.

6. InterventionA simple stepped-care protocol for hypertension treatment, adapted from the 2017 American College of Cardiology/American Heart Association hypertension clinical guideline, was implemented to achieve a target SBP <130 mmHg and DBP <80 mmHg.

7. Implementation StrategiesVillage doctors in the intervention group were trained on standardized BP measurement, protocol-based antihypertensive treatment, and health coaching.Village doctors initiated and titrated antihypertensive medications, conducted health coaching on lifestyle modification and medication adherence, and followed patients up monthly.Village doctors were supervised by primary-care physicians from township hospitals and hypertension specialists at city or county hospitals.Patients in the intervention villages received discounted or free antihypertensive medications, home BP monitors, and health coaching.

8. Statistical AnalysisIntention-to-treat analyses was conducted. The difference in the proportions of patients with controlled blood pressure between the two comparison groups was tested using a generalized linear mixed-effects model. Cluster effects were accounted for by assuming a compound-symmetry covariance structure. The net differences in mean blood pressure changes between the intervention and control groups were tested using a linear mixed-effects model. Participants and villages were assumed to be random effects, and the intervention was assumed to be a fixed effect.We also conducted prespecified subgroup analyses by age, sex, education level, history of antihypertensive treatment, and baseline risk for cardiovascular disease.

9. Baseline Characteristics of Study Participants CharacteristicsIntervention(n=17,407)Control(n=16,588)Age (years), mean (SD)62.8 (9.2)63.2 (9.2)Women, No. (%)10,603 (60.9)10,222 (61.6)High-school education, No. (%)5,872 (34.0)5,254 (32.0)Use of antihypertensive medications, No. (%)10,574 (60.7)8,990 (54.2)Duration of hypertension (years), median (IQR)7 (5-11)7 (4-11)Body-mass index (kg/m2), mean (SD)26.0 (3.9)25.8 (3.8)Systolic blood pressure (mmHg), mean (SD)157.0 (18.0)155.5 (17.3)Diastolic blood pressure (mmHg), mean (SD)88.1 (10.7)87.3 (10.6)10-year risk for atherosclerotic CVD (%), mean (SD) 14.6 (11.9)14.4 (11.6)

10. Effectiveness of the Village Doctor-Led Intervention on the Primary and Secondary Outcomes Study outcomesProportion or mean change (95% CI)Net difference (95% CI)P valueInterventionUsual carePrimary outcomeProportion of patients with BP <130/80 mmHg at 18 months, %57.0 (55.3, 58.7)19.9 (18.7, 21.2)37.0 (34.9, 39.1)<0.001Secondary and other outcomesProportion of patients with BP <140/90 mmHg at 18 months77.3 (75.8, 78.8)44.5 (43.0, 46.1)32.7 (30.6, 34.9)<0.001Change in SBP from baseline to 18 months, mmHg-26.3 (-27.1, -25.4)-11.8 (-12.6, -11.0)-14.5 (-15.7, -13.3)<0.001Change in DBP from baseline to 18 months, mm Hg-14.6 (-15.1, -14.2)-7.5 (-7.9, -7.2)-7.1 (-7.7, -6.5)<0.001

11. Proportion of Patients with Controlled Blood Pressure During Trial Follow-up Blood Pressure < 130/80 mm HgBlood Pressure < 140/90 mm Hg

12. Mean Systolic and Diastolic Blood Pressure During Trial Follow-up Systolic Blood PressureDiastolic Blood Pressure

13. SubgroupsInterventionControlGroup Difference, % (95% CI)No. of patientsProportion, %No. of patientsProportion, %Age, years ≥6010,08755.89,76318.936.9 (34.7, 39.1) <605,32759.74,73722.237.4 (34.8, 40.0)Sex Men5,92455.25,47418.836.4 (33.9, 38.9) Women9,49058.4 9,02620.637.7 (35.5, 40.0)Education ≥High school5,14658.94,57121.237.7 (35.0, 40.4) <High school 10,15156.49,77719.437.0 (34.7, 39.2)Antihypertensive medication use Yes9,37356.47,87218.937.5 (35.2, 39.8) No6,04158.06,62820.837.2 (34.7, 39.7)Cardiovascular risk High6,93153.66,43018.135.5 (33.1, 37.9) Not high8,01760.67,56921.838.9 (36.5, 41.2)Overall15,41457.014,50019.937.0 (34.9, 39.1)P value for Homoge-neity0.950.210.890.820.003Proportions of Patients with BP <130/80 mmHg at 18 Months by Subgroups

14. SummaryAt 18 months, the proportion of patients who achieved BP <130/80 mmHg was 57.0% in intervention and 19.9% in control, with a group difference of 37.0% (95% CI: 34.9% to 39.1%; P<0.001). Mean systolic and diastolic BP decreased by -26.3 and -14.6 mmHg from baseline to 18 months in intervention and by -11.8 and -7.5 mmHg in control, respectively, with a net difference of -14.5 mmHg (95% CI: -15.7 to -13.3 mmHg; P<0.001) for systolic and -7.1 mmHg (-7.7 to -6.5 mmHg; P<0.001) for diastolic BP.

15. ConclusionThe village doctor-led multifaceted intervention significantly improved blood pressure control among rural residents in China. This feasible, effective, and sustainable implementation strategy could be scaled up in rural China and other low-resource settings for hypertension control, with the overall aim of reducing cardiovascular disease and all-cause mortality.

16. AcknowledgementsThe China Rural Hypertension Control Project was supported by the Ministry of Science and Technology of China (grant number 2017YFC1307600). The US investigators did not receive any financial support from this study. We thank the CRHCP investigators, research staff, primary care providers, village doctors, and patients for their contribution to this work.