The predictors of recovery from diabetes mellitus following neurosurgical treatment of acromegaly: A prospective study over a decade

Objective: The natural history of glucose intolerance (GI) in patients with acromegaly undergoing surgical treatment has not been fully understood. This study was aimed to unravel the prevalence and predictors of recovery from GI in these patients in a prospective multivariate model. Materials and Methods: Patients with acromegaly treated between 2007 and 2016 were prospectively studied with respect to demographics, clinicoradiological features, comorbidities, and hormonal investigations before surgery and at regular follow-up. The independent predictors of recovery from diabetes were analyzed. Results: There were a total of 151 patients with active acromegaly included in the study. The median baseline growth hormone (GH) and insulin-like growth factor (IGF)-I levels were 25 and 811 ng/mL, respectively. Diabetes mellitus (DM) and pre-diabetes were noted in 93 (61.6%) and 20 (13.2%) patients, respectively. Following surgical treatment, the median HbAlc decreased significantly from 6.4% to 5.5% (P < 0.001), with 46.8% having complete recovery from DM or pre-diabetes. This glycemic recovery had significant association with both biochemical (P= 0.001) and radiological remission (P= 0.01). The recovery from DM had a greater association with post-operative IGF-1 than GH, especially among those with discordant GH and IGF-1 levels (60% in normal IGF-1 and high GH vs. 20% in high IGF-1 and normal GH). Post-operative IGF-1 had a significant impact on recovery from DM (P = 0.01) independent of age, body mass index, duration of DM, and pre-operative HbAlc. Conclusion: Nearly half of the patients with acromegaly with DM or pre-diabetes had glycemic recovery, influenced by biochemical and radiologic remission. Post-operative IGF-1 appears to be the strongest independent determinant of recovery from DM.