Abstract
Abstract
Background
Suboptimal glycemic control remains a significant public health challenge among adults with type 2 diabetes and prediabetes, with 47.4% of US adults with diagnosed diabetes having hemoglobin A
1c
(HbA
1c
) ≥7%. Remote glucose monitoring programs have shown promise for supporting self-management, but real-world evidence on the causal impact of varying patient engagement levels on glycemic outcomes remains limited.
Objective
This study aimed to estimate the causal dose-response relationship between patient engagement, operationalized as weekly glucose monitoring frequency, and glycemic control measured by HbA
1c
among adults enrolled in a comprehensive primary care–integrated remote monitoring program.
Methods
We conducted a retrospective cohort study of 1436 adults with type 2 diabetes or prediabetes enrolled in the Unika Health program between 2019 and 2024. The program integrated Bluetooth-connected glucose meters, a mobile app, structured lifestyle coaching, and primary care coordination across 74 physician practices. Engagement was defined as mean weekly glucose monitoring frequency during the first 6 months. The causal effect of monitoring frequency on 6-month HbA
1c
was estimated using marginal structural models (MSMs) with inverse probability weighting to address time-varying confounding. Covariates included age, sex, BMI, baseline HbA
1c
, comorbidities, medication status, and physical activity level.
Results
The cohort was predominantly older (95.4%, 1370/1436 aged ≥46 years), with 82.6% (1186/1436) having hypertension and 45.9% (659/1436) classified as obese. Overall, HbA
1c
decreased by a mean of 0.54 (SD 1.47; 95% CI 0.47‐0.62) percentage points (
P
1c
reductions of 0.38 (SD 1.40; 95% CI 0.29‐0.48), 0.71 (SD 1.50; 95% CI 0.58‐0.85), and 1.01 (SD 1.67; 95% CI 0.69‐1.32) percentage points for the low, medium, and high tiers, respectively (all
P
t
test). In weighted MSMs, each additional weekly measurement was associated with a 0.05 (95% CI 0.03‐0.07) percentage point greater HbA
1c
reduction (
P
1c
(≥9%), the high-engagement group achieved a mean reduction of 3.12 (SD 1.97; 95% CI 2.29‐3.94) percentage points. Findings were consistent in sensitivity analyses at 3 months (β=−0.04;
P
P
=.003) and across alternative weighting specifications.
Conclusions
Higher engagement with a digitally enabled, primary care–integrated remote glucose monitoring program was causally associated with significantly greater HbA
1c
reductions in adults with type 2 diabetes and prediabetes. These findings support scalable remote patient monitoring strategies that actively foster sustained patient engagement as an effective approach to improving glycemic control and reducing the burden of diabetes-related complications at a population level.