(P23-069-23) Medical Nutrition Therapy From a Registered Dietitian Nutritionist Improves Outcomes in Adults with Pre-Hypertension or Hypertension: Systematic Review and Meta-Analysis

Objectives: The purpose of this systematic review and meta-analysis was to determine the efficacy of medical nutrition therapy (MNT) provided by a registered dietitian nutritionist or international equivalent (dietitian), compared to usual care, on blood pressure (BP) and other related outcomes in adults with pre-hypertension or hypertension.

Methods: Multiple databases were searched to identify eligible randomized controlled trials (RCTs) published between 1985 and August 2022. Meta-analyses were conducted using a random-effects model. Continuous outcomes were reported as mean difference (MD) or standardized mean difference (SMD) and 95% confidence interval (95% CI). Risk of bias was evaluated using the RoB 2.0 tool and quality of evidence was determined using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) method.

Results: Of 3,693 articles identified, 41 were included in this review, representing 30 RCTs. Compared to usual care, MNT provided by a dietitian significantly improved measures of vascular health, including systolic BP [MD (95% CI): -3.63 mmHg (-4.35, -2.91)], diastolic BP [-2.02 mmHg (-2.56, -1.49)], and arterial stiffness [SMD (95% CI): -0.45 (-0.71, -0.19)]. Significant reductions in anthropometric measures were also observed, including body mass index (BMI) [MD (95% CI): -0.25 kg/m² (-0.45, -0.19), body weight (BW) [-1.84 kg (-2.72, -0.96)], and waist circumference (WC) [-1.20 cm (-2.12, -0.29)]. Furthermore, MNT provided by a dietitian significantly reduced CVD risk score [SMD (95% CI): -0.20 (-0.30, -0.09)] and the risk of stroke [relative risk (95% CI): 0.39 (0.17, 0.88)], while there was no effect on risk of myocardial infarction (MI) [relative risk (95% CI): 0.85 (0.51, 1.42)]. Certainty of evidence was as follows – Low: systolic and diastolic BP, arterial stiffness, BW, WC, and risk of MI; Moderate: BMI, CVD risk score, and risk of stroke.

Conclusions: For adults with pre-hypertension or hypertension, MNT provided by a dietitian is effective in improving key CVD risk factors and events. Thus, improved payment for and access to MNT services can address elevated blood pressure, one of the strongest risk factors for CVD, and has the potential to significantly impact public health.

Funding Sources: Academy of Nutrition and Dietetics Foundations’ Evidence Analysis Library Foundation Research Endowment