# Comparison of Patients Classified as High-Risk between International Cardiovascular Disease Primary Prevention Guidelines

## TL;DR

This study compares how different countries classify people at high risk for heart disease and finds significant differences in who is recommended for treatment.

## Contribution

The study reveals discrepancies in high-risk classification and treatment recommendations across international CVD prevention guidelines.

## Key findings

- The U.S. guidelines recommended treatment for nearly half of participants, while Australian guidelines recommended it for only 26.6%.
- Agreement in treatment recommendations was moderate between U.S. and England guidelines but minimal between Australia and U.S.
- Findings suggest a need for more consistent high-risk classification across international CVD prevention guidelines.

## Abstract

Background: Cardiovascular disease (CVD) primary prevention guidelines classify people at high risk and recommended for pharmacological treatment based on clinical criteria and absolute CVD risk estimation. Despite relying on similar evidence, recommendations vary between international guidelines, which may impact who is recommended to receive treatment for CVD prevention. Objective: To determine the agreement in treatment recommendations according to guidelines from Australia, England and the United States. Methods: Cross-sectional analysis of the National Health and Nutrition Examination Survey (n = 2647). Adults ≥ 40 years were classified as high-risk and recommended for treatment according to Australia, England and United States CVD prevention guidelines. Agreement in high-risk classification and recommendation for treatment was assessed by Kappa statistic. Results: Participants were middle aged, 49% were male and 38% were white. The proportion recommended for treatment was highest using the United States guidelines (n = 1318, 49.8%) followed by the English guidelines (n = 1276, 48.2%). In comparison, only 26.6% (n = 705) of participants were classified as recommended for treatment according to the Australian guidelines. There was moderate agreement in the recommendation for treatment between the English and United States guidelines (κ = 0.69 [0.64–0.74]). In comparison, agreement in recommendation for treatment was minimal between the Australian and United States guidelines (κ = 0.47 [0.43–0.52]) and weak between the Australian and English guidelines (κ = 0.50 [0.45–0.55]). Conclusions: Despite similar evidence underpinning guidelines, there is little agreement between guidelines regarding the people recommended to receive treatment for CVD prevention. These findings suggest greater consistency in high-risk classification between CVD prevention guidelines may be required.