A number of systematic reviews were published with regard to diabetes interventions in primary care and community settings. Previous systematic reviews found that lifestyle interventions, social network interventions, or interventions using community health workers and mHealth were effective in improving glucose control. Additionally, motivational interviewing by general practitioners and nurse-led self-management support interventions resulted in a significant improvement in glucose control. No prior systematic review specifically addressed CHC interventions for diabetes. Given CHCs serving as primary care homes for the nation’s most vulnerable populations, a comprehensive systematic review on CHC interventions to control diabetes among vulnerable populations is needed.
Purpose: The purpose of this study is to synthesize the evidence on CHC interventions. Specifically, we examined the characteristics of CHC interventions and the patient outcomes in people with diabetes. Our review systematically extends the previous efforts by providing an understanding of: 1) what constitutes CHC interventions (type and contents); 2) who delivers CHC intervention; and 3) how CHC interventions achieve desired effects.
Methods: Four electronic database searches, including PubMed, Embase, Cumulative Index to Nursing and Allied Health Literature (CINAHL), and SCOPUS, and hand searches of reference collections were undertaken in January 2018 to identify intervention trials published in English. A total of 892 unique citations were screened initially for titles and abstracts. Two reviewers then independently evaluated 236 full-text articles that were passed onto review processes. Thirty studies met eligibility criteria for inclusion.
Results: All of the 30 studies were conducted in the United States. The CHC interventions included in the review varied greatly in terms of type and modality of the interventions. Twelve interventions used one-on-one education sessions with three of the studies incorporating follow-up telephone calls to answer patient’s questions. Five interventions used group education sessions with the education sessions ranging from one to twelve sessions. Five CHC interventions used the telephone as the main method of communication with one intervention sending daily text messages. Other intervention methods included one diabetic complication screenings and a 1-day workshop that focused on mindfulness as a way to improve one’s management of diabetes. CHC interventions were delivered by various health professionals including registered nurses, dieticians and nutritionists, medical assistants, community health workers, pharmacists, physicians, and nurse practitioners. More than half of the studies included in this review lacked full descriptions of interventionists in terms of selection and training and fidelity monitoring, however.
CHC intervention patient outcomes focused on clinical measures including: HbA1c levels (n=23), blood pressure (n=10), and cholesterol (n=12) as well as diabetes self-management (n=7), and goal setting (n=4). CHC interventions using individual education sessions (5 of 12) and group-education sessions (2 of 5) had significant improvements in HbA1c, while sole telemedicine education studies (n=5) showed no significant improvements in HbA1c. In addition, one study of eleven in which mental health outcomes were measured showed significantly reduced depression scores after receiving the CHC intervention. CHC interventions had no significant effects on physical activity in all six studies that examined physical activity.
Conclusion: CHC interventions were generally effective in HbA1c reduction either via individual education or group education, although insignificant HbA1c results were noted in ten of twenty-three studies that examined HbA1c. CHC interventions were also effective in improving lipids and systolic blood pressure among persons with diabetes but only a small number of studies addressed them as study outcomes. Similarly, there was only limited evidence to show that CHC interventions were effective in improving diabetes knowledge, self-management, diabetes related distress, screening for complications, goal attainment, and self-efficacy. There is a strong need for studies to clearly elaborate the contents and processes of interventionists training such as competency evaluation and supervision to optimize the use of the CHC approach. Additionally, in many CHC interventions included in the review, possible cost-efficient model of care may be considered for next line of inquiries. In particular, the U.S. Affordable Care Act—also called Obamacare—aims to increase the quality and affordability of health insurance by expanding public and private insurance coverage while reducing the costs of healthcare for individuals and the government. Community health workers are an important part of healthcare teams for the delivery of care, particularly among medically underserved populations and communities. Clearly, more systematic cost evaluations of collaborating with community health workers as an alternate care model at the CHC is warranted to expedite the translation of research into evidence-based guidelines and recommendations for clinical practice in vulnerable populations.