# Assessing compliance with national guidelines in diabetes care: A study leveraging data from south Africa’s National Health Laboratory Service (NHLS)

## TL;DR

This study found that diabetes patients in South Africa are not being monitored as frequently as national guidelines recommend, even after a laboratory diagnosis.

## Contribution

The study uses a regression discontinuity design to assess compliance with diabetes monitoring guidelines in a national laboratory cohort.

## Key findings

- Among type 2 diabetes patients, 52.4% had follow-up tests above the diagnostic threshold vs 31.1% below.
- No clinically meaningful difference in follow-up testing was observed at the diagnostic threshold.
- Results were consistent across type 1 diabetes, HIV status, and healthcare settings.

## Abstract

Diabetes is a major global health issue. We evaluated compliance to laboratory-based management guidelines for diabetes (type 1 and 2), essential for effective treatment and reducing diabetes-related morbidity and mortality. Our study utilized South Africa’s National Health Laboratory Services (NHLS) data, focusing on patients from birth to age 80 years who underwent initial diabetes laboratory testing between January 1, 2012-January 1, 2016. Patients were categorized into type 1 (<30 years) or type 2 (≥30–80 years) diabetes based on age at first diabetes test. National diabetes guidelines recommend blood glucose to be checked every three-six months post laboratory-diagnosis. We employed a sharp regression discontinuity design to estimate the effect of a laboratory-diagnosis of diabetes on the likelihood of having a follow-up laboratory test 24 months post-diagnosis. Among patients with type 2 diabetes, the probability of a diabetes follow-up laboratory test within 24 months was 52.4% for patients presenting above the diabetes diagnosis threshold vs 31.1% for those presenting below. Although the likelihood of repeat testing rose with higher HbA1c and glucose levels, at the diagnostic threshold there was no clinically meaningful difference (risk difference: -2.2%, 95% CI: -3.3%, -1.2%). These results were consistent among patients with type 1 diabetes, those living with and without HIV, and healthcare setting. In a national laboratory cohort, diabetes laboratory-diagnosis did not lead to increased monitoring as recommended in national guidelines. Strategies to improve patient education, healthcare provider communication, and healthcare system support are essential to enhance guideline compliance and overall diabetes management.