Hybrid Closed-Loop Pumps Boost Time-in-Range for T1D

What This Study Found

A 12-week clinical trial in China tested a hybrid closed-loop (HCL) insulin pump system in 126 people with type 1 diabetes — including both adolescents and adults. When participants switched to the pump's automatic mode, their time-in-range (the percentage of the day spent with blood sugar between 70–180 mg/dL) rose from 69% to nearly 77%. At the same time, dangerous blood sugar events — including severe low blood sugar and diabetic ketoacidosis (DKA) — did not occur in any participant.

Why This Matters for You

Time-in-range is one of the most meaningful measures of day-to-day diabetes management. Every extra hour your blood sugar stays in the healthy range reduces stress on your body and lowers the risk of long-term complications like nerve damage, kidney disease, and vision problems.

This study showed that the biggest improvements happened in people who started with an HbA1c above 8.0% — meaning those who were struggling most with control had the most to gain. Their average sensor glucose dropped by more than 30 mg/dL, and blood sugar swings became noticeably smaller.

Key Results at a Glance

• Time-in-range improved: From 69.1% to 76.7%
• Time below range (low blood sugar) decreased: From 3.9% to 2.7%
• Average sensor glucose dropped: From 151 mg/dL to 144 mg/dL
• More people hit the 70% TIR target: Up from 56% to nearly 78%
• Blood sugar variability decreased: Fewer unpredictable highs and lows
• Zero severe hypoglycemia or DKA events

How a Hybrid Closed-Loop System Works

A hybrid closed-loop pump combines a continuous glucose monitor (CGM) with an insulin pump. The two devices communicate automatically. When your CGM senses your blood sugar rising, the pump adjusts your insulin delivery in real time — without you needing to do anything. You still give yourself insulin for meals, but the system handles most of the moment-to-moment adjustments.

Think of it like a thermostat for your blood sugar. Instead of manually adjusting the heat every hour, the system keeps things steady on its own.

What This Means in Practice

This study adds to a growing body of evidence that HCL technology is safe and effective — and not just in Western countries. Seeing strong results in a Chinese population is important because it suggests these benefits are broadly applicable across different groups of people with type 1 diabetes.

If you or your child has type 1 diabetes and is currently using multiple daily injections or a standard insulin pump, it may be worth talking to your diabetes care team about whether a closed-loop system could be a good fit.

Managing insulin pump supplies — including reservoirs, infusion sets, and CGM sensors — is an ongoing part of life with an insulin pump. MDS Diabetes (mdsdiabetes.com) carries a wide range of insulin pump and CGM supplies to help keep your system running smoothly.

Citation: Shen, Zeng, Li (2026). Safety and efficacy of hybrid closed-loop insulin pump therapy in adolescents and adults with type 1 diabetes in China. Diabetes, Obesity & Metabolism. PMID: 41190360. DOI: 10.1111/dom.70227