Corticosteroid injections increase glucose levels in diabetics

Despite increased glucose levels, most patients avoided surgery for upper extremity inflammatory conditions, including trigger finger.

Corticosteroid injections can effectively treat trigger finger and similar upper extremity conditions in diabetic patients. However, such injections can also cause significant increases in blood glucose levels in these patients, a prospective study shows.

In a consecutive series of 18 diabetic patients, researchers at the University of Utah in Salt Lake City found that average blood glucose levels increased 78% over baseline on the first morning postinjection. Additionally, glucose levels remained significantly elevated at five days follow-up, averaging 19% higher than pre-injection levels.

No patients reported any adverse events, however.

“The dangers of hyperglycemia are few in the short term. But given the fact that our patients are diabetic already, we wanted to alert patients to the possibility that their sugars might go very high so they could adjust their medication, if needed,” Angela Wang, MD, an assistant professor of orthopedics at the university and lead author of the study, told Orthopedics Today.

“This study was prompted by a patient I had while I was a fellow, who did go into diabetic ketoacidosis after an injection — an extremely rare [reaction],” she said.

“We feel that because this effect is relatively symptom-free, and that 57% of [trigger finger] patients avoided surgery, injection can remain a reasonable alternative for a patient willing to monitor their own blood sugar,” said Douglas Hutchinson, MD, co-author of the study.

Type 1 and type 2 diabetics

Wang and Hutchinson evaluated the effect corticosteroids had on blood glucose levels in four men and 14 women. These patients had a mean age of 59 years; 13 had type 2 diabetes and five had type 1.

Diagnoses included the following:

trigger finger in 14 cases;
deQuervains tenosynovitis in two cases;
lateral epicondylitis in one case; and
thumb carpometacarpal arthritis in one case.

All injections contained 1% lidocaine without epinephrine and 40 mg/ml methylprednisolone. Each diagnosis had its own reproducible injection method and steroid amount.

Trigger finger patients received 1 cc lidocaine and 0.25 cc methylprednisolone in the palm over the A1 pulley. The one patient with lateral epicondylitis received 3 cc lidocaine and 1 cc methylprednisolone in the lateral epicondyle down to the bone.

Patients with deQuervains tenosynovitis received 1 cc lidocaine and 0.25 cc methylprednisolone in the first dorsal compartment. The one patient with thumb carpometacarpal arthritis received 1 cc lidocaine and 0.25 cc methylprednisolone via an anterior approach volar to the extensor pollicis and brevis tendons, according to the study.

Following treatment, all patients self-monitored blood sugar levels by finger stick twice daily. They also managed their own medication and diet, the authors noted.

Pronounced hyperglycemic effect

The researchers found that every patient experienced a hyperglycemic effect following injection. However, no patients reported suffering any symptoms or medical problems, noted Hutchinson, who presented the study results at the Joint American Society for Surgery of the Hand/American Society for Hand Therapists Annual Meeting in San Antonio.

“When the data was stratified by type 1 and type 2 diabetics, the hyperglycemic effect from the injections was more pronounced in type 1 diabetics as we would expect, with average increases of 215% on postinjection day one,” Hutchinson said.

At five days follow-up, glucose levels in type 1 diabetic patients remained elevated, averaging 36% higher than pre-injection levels. Comparatively, blood glucose levels in type 2 diabetic patients had increased an average of 30% on the first day following injection, Wang said.

The steroid injections were effective in 61% of patients, Hutchinson noted. At an average follow-up of 34 months, only seven of the 18 patients (39%) required surgery — six trigger finger patients and the one lateral epicondylitis patient, according to the study.

“Trigger fingers were operated on due to continued recurrent symptoms in 43%, which is close to the 50% reported by Griggs et al in the Journal of Hand Surgery,” Hutchinson added.

For more information:
Wang A, Hutchinson D. Effect of corticosteroid injection on blood glucose level in diabetic patients. #PAS06. Presented at the Joint Annual ASSH/ASHT Meeting. Sept. 22-24, 2005. San Antonio.
Griggs SM, Weiss AP, Lane LB, Schwenker C, et al. Treatment of Trigger Finger in Patients with Diabetes Mellitus. J Hand Surg. 1995;20:787-789.