Implantable vs. Wearable CGM: Which Works Better?

What Was Studied and Why It Matters

Continuous glucose monitors (CGMs) have transformed diabetes management by tracking blood sugar around the clock — no more relying solely on fingerstick checks. But not all CGMs are built the same. This study asked a simple question: does an implantable CGM sensor (placed under the skin by a clinician and lasting months) perform better or worse than a transcutaneous sensor (the kind you apply yourself at home every week or two)?

Researchers ran a 24-week randomized trial comparing the Eversense implantable sensor to the Dexcom G5 wearable sensor across 16 adults with diabetes. Each person used both devices for 12 weeks, then switched — giving researchers a true apples-to-apples comparison.

What the Study Found

• Accuracy: The implantable Eversense sensor was slightly more accurate than the Dexcom G5 when compared against traditional fingerstick blood sugar readings. Accuracy is measured using a metric called MARD — a lower number means fewer errors. Eversense scored 12.2% vs. Dexcom's 13.1%. Both are clinically acceptable, but the implantable sensor edged ahead.
• Wear time: The Dexcom G5 was actually worn slightly more of the time (95.7% vs. 93.5%). This likely reflects the convenience of self-applying a patch versus scheduling a clinic visit for implantation.
• Blood sugar control (HbA1c): No significant difference in long-term blood sugar control was found between the two devices — both helped patients manage glucose effectively.
• Time in range: Patients using the implantable sensor appeared to spend more time in their target blood sugar range and less time running high, though this finding was less definitive when cross-checked against fingerstick logs.
• Emotional wellbeing: Patients reported less diabetes-related distress while using the implantable sensor — a meaningful quality-of-life benefit that numbers alone don't capture.

What This Means for Real Patients

If you're already using a wearable CGM — or thinking about starting one — this study is reassuring: modern CGM technology, whether implantable or patch-based, delivers reliable glucose data that can meaningfully improve your care. For patients who find frequent sensor changes burdensome, an implantable option may reduce hassle and stress. For those who prefer full control at home, wearable sensors remain highly accurate and easy to use.

Whichever CGM system you use, having the right supplies on hand is essential. MDS Diabetes carries a wide range of CGM accessories and diabetes management supplies to keep your monitoring routine running smoothly.

Talk with your diabetes care team about which CGM type fits your lifestyle, comfort with procedures, and insurance coverage. The "best" device is always the one you'll actually use consistently.

Bottom Line

Both implantable and wearable CGM sensors are accurate and effective tools for managing diabetes. Implantable sensors may offer a slight accuracy edge and reduce emotional distress, while wearable patch sensors are easier to start and used slightly more consistently. Your personal preferences and daily routine should guide which option you choose — and your care team can help you decide.