Pre-emptive Insulin to Prevent High Glucose After a Knee Steroid Injection in Adults With Type 2 Diabetes

Steroid injections used to treat painful joints can temporarily increase glucose levels in people with type 2 diabetes. This study will test whether a short course of pre-emptive neutral protamine Hagedorn, NPH, insulin can reduce high glucose after a standard corticosteroid injection into the knee. Adults with type 2 diabetes who are scheduled to receive one intra-articular injection of triamcinolone acetonide 40 mg for knee osteoarthritis will be randomly assigned to one of two groups. The experimental group will receive a prespecified NPH insulin regimen beginning immediately after the injection and continuing for three doses. The comparison group will continue usual reactive diabetes management without pre-emptive NPH insulin. Both groups will use blinded continuous glucose monitoring and scheduled capillary glucose testing. The main outcome is the percentage of continuous glucose monitoring time above 180 mg/dL during the first 72 hours after the corticosteroid injection. Hypoglycaemia, rescue treatment, healthcare contacts, treatment burden, acceptability and adverse events will also be assessed.