Importance: Interprofessional collaborative practice (ICP), the collaboration of health workers from different professional backgrounds with patients, families, caregivers, and communities, is central to optimal primary care. However, limited evidence exists regarding its association with patient outcomes.
Objective: To examine the association of ICP with hemoglobin A1C (HbA1c), systolic blood pressure (SBP), and diastolic blood pressure (DBP) levels among adults receiving primary care.
Data Sources: A literature search of English language journals (January 2013-2018; updated through March 2020) was conducted using MEDLINE; Embase; Ovid IPA; Cochrane Central Register of Controlled Trials: Issue 2 of 12, February 2018; NHS Economic Evaluation Database: Issue 2 of 4, April 2015; Clarivate Analytics WOS Science Citation Index Expanded (1990-2018); EBSCOhost CINAHL Plus With Full Text (1937-2018); Elsevier Scopus; FirstSearch OAIster; AHRQ PCMH Citations Collection; ClinicalTrials.gov; and HSRProj.
Study Selection: Studies needed to evaluate the association of ICP (≥3 professions) with HbA1c, SBP, or DBP levels in adults with diabetes and/or hypertension receiving primary care. A dual review was performed for screening and selection.
Data Extraction and Synthesis: This systematic review and meta-analysis followed the PRISMA guideline for data abstractions and Cochrane Collaboration recommendations for bias assessment. Two dual review teams conducted independent data extraction with consensus. Data were pooled using a random-effects model for meta-analyses and forest plots constructed to report standardized mean differences (SMDs). For high heterogeneity (I2), data were stratified by baseline level and by study design.
Main Outcomes and Measures: The primary outcomes included HbA1c, SBP, and DBP levels as determined before data collection.
Results: A total of 3543 titles or abstracts were screened; 170 abstracts or full texts were reviewed. Of 50 articles in the systematic review, 39 (15 randomized clinical trials [RCTs], 24 non-RCTs) were included in the meta-analyses of HbA1c (n = 34), SBP (n = 25), and DBP (n = 24). The sample size ranged from 40 to 20 524, and mean age ranged from 51 to 70 years, with 0% to 100% participants being male. Varied ICP features were reported. The SMD varied by baseline HbA1c, although all SMDs significantly favored ICP (HbA1c <8, SMD = -0.13; P < .001; HbA1c ≥8  to < 9, SMD = -0.24; P = .007; and HbA1c ≥9, SMD = -0.60; P < .001). The SMD for SBP and DBP were -0.31 (95% CI, -0.46 to -0.17); P < .001 and -0.28 (95% CI, -0.42 to -0.14); P < .001, respectively, with effect sizes not associated with baseline levels. Overall I2 was greater than 80% for all outcomes.
Conclusions and Relevance: This systematic review and meta-analysis found that ICP was associated with reductions in HbA1c regardless of baseline levels as well as with reduced SBP and DBP. However, the greatest reductions were found with HbA1c levels of 9 or higher. The implementation of ICP in primary care may be associated with improvements in patient outcomes in diabetes and hypertension.