Glucocorticoid epidural for sciatica: metabolic and endocrine sequelae

Abstract

Objective. The study was designed to investigate the effect of epidural administration of glucocorticoid on insulin sensitivity.

Methods. Ten healthy individuals with sciatica underwent a short insulin tolerance test before and twice following (at 24 h and 1 week) a caudal epidural containing 80 mg triamcinolone. Fasting glucose, insulin and cortisol concentrations were also measured.

Results. The rate of glucose disappearance after insulin administration (k_ITT) fell from 3.6%/min before the epidural to 1.9%/min 24 h afterwards (P=0.001) and returned to pretreatment values by 1 week. Significantly raised fasting insulin and glucose levels also reflected impaired insulin sensitivity immediately after the epidural. Morning cortisol levels were suppressed after the epidural (49 nmol/l at 24 h and 95 nmol/l at 1 week vs 352 nmol/l at baseline; P<0.01).

Conclusions. Epidural administration of glucocorticoid results in potent suppression of insulin action and this should be taken into account when patients with diabetes require treatment for sciatica.

Glucocorticoid, Insulin sensitivity, Epidural, Adrenal suppression, Sciatica.