Performance of a safety protocol for scuba diving in people with type 1 diabetes: 20 years of “Diabete Sommerso®” experience

Background and aims: Scuba diving for people with diabetes was discouraged due to hypoglycemia risks. However, evolving guidelines now enable safe diving for people with diabetes. Among them, the Diabete Sommerso® safety protocol. This study aims to describe data from 20 years of DS activities and evaluate the performance of the protocol in avoiding metabolic complications. Research design and methods: During DS camps, participants are trained to monitor glycemia before and immediately after diving, aiming for stable levels between 150–250 mg/dl. Since 2004, glycemic data from dives conducted with DS/independently by its members have been collected. Results: DS issued diving licenses to 74 type 1 diabetic people. Data are available for 68: median age was 32 years (IQR 22 yrs), diabetes duration 18 years (IQR 16 yrs), HbA1c 7 % (IQR 1 %). 34 used insulin pumps, 43 continuous glucose monitoring. A total of 1179 dives were analyzed, showing a median reduction in glycemia of −38 mg/dl during dives (IQR 92 mg/dl, p < 0.0001). Post-dive hypoglycemia occurred in 23 cases, 45 % of which involved protocol non-adherence. Hypoglycemia prevalence was 1.7 % when the protocol was followed. No severe hypoglycemic episodes occoured during/after diving. Conclusions: Data from 1179 dives indicate that, with adherence to the safety protocol, scuba diving is safe and poses no risk of severe hypoglycemia for people with type 1 diabetes.