Lack of effect of corticosteroid injection at the shoulder joint on blood glucose levels in diabetic patients

The effect of systemic glucocorticosteroids on the metabolism of glucose is well known; however, there are no reports on the effect of intraarticular steroids on the metabolism of glucose in diabetic patients. Controlled or near controlled diabetic patients who have self-monitoring devices for home monitoring of blood glucose with shoulder pain were offered an intraarticular crystalloid steroid injection of 35 mg of methylprednisolone acetate (MPA) at the shoulder joint after failure of pharmacological and physical therapy. Patients were asked to record blood glucose levels before and 2 h after breakfast, lunch, and supper (six times a day) every other day during 1 week before the injection and during the day of the injection, the next day and every other day for 2 weeks after the injection. Fructosamine levels were obtained just before the injection and 2 weeks after the injection. Wilcoxon signed rank test was used to compare the mean glucose levels before with those after the injection. Paired t test was used to compare the mean fructosamine values after the injection with those before the injection. Eighteen patients completed the study. Fifteen had adhesive capsulitis. The mean glucose levels before injection were 165.5, 195.5, 184.6, 199.4, 182.8, and 200.7 mg% before and 2 h after breakfast, lunch, and supper, respectively. There was no significant change between the mean glucose values before and after meals after the injection compared to those before the injection, respectively, except on a few occasions only throughout the study period. Mean fructosamine level before injection was 279 μmol/l±49.8 compared to 275 μmol/l±50.9 after the injection (P=0.125). Intraarticular injection of MPA at the shoulder joint in diabetic patients with shoulder pain has no significant effect on blood glucose levels.