Effect of a Coordinated Community and Chronic Care Model Team Intervention vs Usual Care on Systolic Blood Pressure in Patients With Stroke or Transient Ischemic Attack

Key Points Question Is a team-based community health worker and advanced practice clinician (including nurse practitioners or physician assistants) intervention emphasizing evidence-based care, self-management, lifestyle change, and medication adherence superior to usual care for controlling blood pressure after stroke in safety-net settings? Findings In this randomized clinical trial that included 487 adults with recent stroke or transient ischemic attack, there was no difference between usual care and the multifaceted team-based intervention in blood pressure control at 12 months. Meaning These findings suggest that additional research is needed to determine the optimal care model for controlling risk factors after stroke in safety-net settings.


Introduction
Approximately 1 in 4 strokes in the United States are recurrent. 1 Combining dietary changes, physical activity, and targeted medications can reduce the cumulative risk for recurrent vascular events after stroke by 80%. 2 Nevertheless, risk factor control among survivors of stroke remains poor, with only a small portion of individuals reaching recommended targets. [3][4][5][6] Independent factors associated with poor risk factor control include minority race/ethnicity (eg, Black or Hispanic), poverty, and lower education level. [4][5][6] The chronic care model (CCM), which incorporates self-management support, delivery system redesign, clinical information systems with decision support for applying evidence-based care guidelines, health care system leadership engagement, and community resources, has been effective in improving outcomes while reducing costs for chronic conditions. 7-10 A randomized clinical trial of a CCM-based intervention by Cheng et al 11 did not show a benefit beyond usual care in blood pressure (BP) reduction in a predominantly Hispanic population treated for stroke in a safety-net setting (ie, health care setting where all individuals receive care, regardless of health insurance status or ability to pay). The intervention, delivered solely within the health care system by advanced practice clinicians (APCs; including nurse practitioners or physician assistants), did not address home and community barriers to lifestyle change or transportation barriers to accessing care.
We hypothesized that community health workers (CHWs) could more effectively address lifestyle factors, health literacy, medication adherence, and obstacles to behavior change. Therefore, we developed a multilevel, multicomponent, complex CCM-based team (including an APC, a CHW, and a physician) intervention for improving poststroke risk factor control. 12 The intervention redesigned care at the health care system level with evidence-based care protocols with real-time electronic decision support and enhanced care coordination and at the patient level by targeting health and stroke literacy, medication adherence, self-management skills, and lifestyle (eFigure in Supplement 1). We tested the efficacy of the Secondary Stroke Prevention by Uniting Community and Chronic Care Model Teams Early to End Disparities (SUCCEED) intervention in improving risk factor control after stroke at 12 months in a safety-net setting.

Methods
Institutional review board approvals were obtained at University of California, Los Angeles and at each of the 5 sites (or through reliance agreements with UCLA). All participants provided written informed consent. This study is reported following the Consolidated Standards of Reporting Trials (CONSORT) reporting guideline. The Trial Protocol is presented in Supplement 2.

Setting and Participants
Study details have been previously published. 12 The intervention was framed by the Health Belief Model. 13 Briefly, of 887 screened participants, 542 were eligible, and 487 were enrolled from experience of transient ischemic attack (TIA), ischemic stroke, or intracerebral hemorrhage within the last 90 days; and elevated systolic BP. Elevated systolic BP was defined as greater than 120 mm Hg, consistent with existing guidelines. 14 During the course of the trial, evidence of a potential J-shaped curve emerged among individuals who survived stroke, with a suggestion of higher risk for cardiovascular events with strict BP control. [15][16][17][18] Therefore, 16 months after initiating the trial (after enrolling 154 participants), the systolic BP goal at 12 months was increased from less than 120 mm Hg to less than 130 mm Hg. Correspondingly, inclusion criteria were revised to systolic BP 130 mm Hg or greater or 120 to 130 mm Hg in individuals with a history of hypertension or using antihypertensive medications prior to the stroke or TIA. Participants were excluded if they were unable to

Statistical Analysis
Data analysis was performed from October 2018 to November 2020. Comparisons of baseline characteristics between usual care and intervention arms and between participants who completed the 12-month survey vs those who did not were conducted using the 2-sample t test, χ 2 test, Fisher exact test, or Wilcoxon rank-sum test, depending on the nature of the data.
Outcomes were compared using baseline and 12-month time points and using repeatedmeasures mixed-effects models that included baseline, 3-month, 8-month (only for knowledge of stroke factors and medication adherence), and 12-month data. All analyses used an intent-to-treat approach. Stratification variables (ie, site, language, stroke type) were included in repeated measures models as covariates. The key analysis was interaction of time and study arm. The bootstrap method was used to calculate 95% CIs and 2-sided P values for some variables. A 5% level of significance was used throughout.
Four sensitivity analyses were performed for the repeated measures models (eAppendix in Supplement 1); 2 of these sensitivity models included attrition weights determined by a logistic model with survey language, age, and marital status as predictor variables. In addition, an analysis of primary and secondary outcomes with an indicator variable for the ordinal categories of implementation (as a covariate) by dose was conducted. Intervention participation was classified into 5 categories a priori: (1) 3 or more clinic visits, 3 or more home visits, and 4 or more CDSMP classes; (2) 3 or more clinic visits, 3 or more home visits, and fewer than 4 CDSMP classes; (3) 2 or more clinic visits and 2 or more home visits; (4) fewer than 2 clinic visits and fewer than 2 home visits; and (5) no intervention. For participants randomized to the intervention, a multivariable analysis evaluated the independent association of each core component (clinic visit, home visit, and CDSMP) on 12-month change in BP. Covariates included site, stroke type (ischemic stroke or TIA vs ICH) and language. Core components were dichotomized: 3 or more vs fewer than 3 clinic visits; 3 or more vs fewer than 3 home visits, and 4 or more vs fewer than 4 CDSMP classes.

JAMA Network Open | Neurology
Among participants with ischemic stroke, the relative risk reduction (RRR) of recurrent stroke achieved in each study arm and modified Global Outcome Score (representing the proportion of potentially preventable stroke risk reduction achieved with the level of care provided at the end of the trial, given the level of care received at the beginning of the trial) were calculated (eAppendix in Supplement 1). 40

Results
Of 487 enrolled participants, the mean (SD) age was 57. Intervention and usual care groups were not significantly different with respect to baseline sociodemographic characteristics (Table 1); however, the intervention arm had a lower percentage of participants watching or reducing their salt intake and higher log CRP at baseline (eTable 3 in Supplement 1).
A total of 412 participants (84.6%) completed the 12-month visit. At follow-up, there were no differences in the mean systolic BP improvement nor in the proportion achieving systolic BP control across arms, though systolic BP improved within each arm ( analyses did not differ from the main analysis for any of the primary or secondary outcome measures. Regarding factors associated with mediating outcomes, compared with usual care, at 12 months, participants in the intervention group had a greater increase in BP monitor use, number of appointments with APCs, and statin use (for participants with ischemic stroke or TIA) ( Table 3).
There were no differences between groups over time for other factors associated with mediation.  Analysis of primary and secondary outcomes by implementation category (or dose) as a covariate did not show a dose response pattern. Figure 2 shows baseline and 12-month systolic BP by dose; changes in systolic BP did not show a dose response pattern. Multivariable analysis showed that none of the 3 core components of the intervention had a unique, significant impact on BP reduction.

JAMA Network Open | Neurology
Among participants with ischemic stroke, the estimated achieved RRR for recurrent stroke was modest at 15% (95% CI, 5% to 30%; P < .001) in the experimental group and represented one-fifth the benefit that would have been possible, given baseline risk factors and the potential impact of each risk factor intervention (modified GO score, 0.20 [95% CI, 0.06-0.38]; P = .009). Results did not differ from those in the usual care group (eTable 5 in Supplement 1).

Discussion
In this randomized clinical trial of a team-based complex intervention for improving poststroke risk factor control in a racially/ethnically diverse safety-net population, the primary outcome of systolic BP improved in both intervention and control groups, without significant differences between groups. Among secondary outcomes, participants in the intervention group had larger improvements compared with usual care in self-reported salt intake and CRP level. Of hypothesized mediators, the intervention was associated with BP self-monitoring, number of visits with APCs, and statin use. Modified GO score results suggest that trial participants in both groups averted a mean of less than one-fifth of the risk of ischemic stroke they could potentially have prevented. In both study arms, despite salutary changes in BP and smoking, when considered in concert with mild worsening of non-HDL cholesterol and antithrombotic use, the relative reduction in recurrent stroke risk was likely small.          h Scored on a scale of 1 to 5, with 1 indicating strongly disagree and 5 indicating strongly agree.
i Health care was rated on a scale of 0 (worst) to 10 (best); data here refer to patients who rated care as 6 to 10. j Scores range from 0 to 27, with higher score indicating more severe depression. k Scores range from 0 to 1, with higher score indicating better quality of life.

Strengths and Limitations
This study has several strengths, including aiming to address poststroke risk factor control in a racially/ethnically diverse, high-risk population; using a theory-based behavioral intervention model; incorporating evidence-based components (eg, CCM, electronic decision support, CDSMP, and CHW

mo Baseline
Interventions received Individuals randomized to the intervention group were categorized by the extent of the intervention they received: (1) at least 3 clinic visits, at least 3 home visits, and at least 4 Chronic Disease Self-Management Program (CDSMP) classes; (2) at least 3 clinic visits, at least 3 home visits, and fewer than 4 CDSMP classes; (3) at least 2 clinic visits and at least 2 home visits; (4) fewer than 2 clinic visits and fewer than 2 home visits; and (5) no intervention. Changes between baseline and 12 months were not significantly different across groups. home visits); adapting the intervention from lessons learned from a prior randomized clinical trial in the same setting 11 ; framing the intervention with a conceptual model accounting for the mechanism of change anticipated based on literature and our prior experience 12 ; community involvement in design and implementation of the intervention; allowing individual and site level variability; comprehensive intervention team training; weekly team meetings to ensure adherence to protocols and address barriers in implementation; rigorous standards for biomarker and survey collection; assessment of numerous mediators, moderators, and outcomes; and modeling the impact of multiple interventions using a recurrent stroke risk reduction tool. Many of these strengths are essential elements for developing and evaluating complex interventions. 46

JAMA Network Open | Neurology
This study also has several limitations. First, the population enrolled and retained in the trial may not be representative of the entire patient population. Second, the sample size did not take into account variability in intervention delivery. Third, all CHWs were Hispanic and bilingual in English and Spanish, limiting cultural concordance with other ethnic groups. Fourth, by addressing numerous vascular risk factors and permitting tailoring, the impact of the intervention on the primary outcome may have been diluted. Fifth, variations in care delivery by clinician, site, and situation were incompletely characterized.

Conclusions
This randomized clinical trial did not find a difference between a complex multicomponent intervention and usual care in poststroke systolic blood pressure control in participants from safety-net settings who had experienced a recent stroke. Future studies may consider characterizing why, how, and to what extent components of the SUCCEED intervention were tailored, examining which tools and strategies were preferred for addressing each of the mediators, and assessing the extent to which evidence-based protocols were followed by the care team. Future studies may consider focusing efforts on a more select suite of interventions with the strongest evidence to reduce recurrent stroke risk; determining the effectiveness of SUCCEED if fully implemented, enhanced, or simplified; using a more racially/ethnically diverse group of APCs and CHWs; and further addressing social determinants of health.