Endocrine Abstracts

JOINT1297

Background: Patients with endogenous Cushing’s syndrome (CS) face an elevated cardiometabolic risk, which is linked to increased morbidity and mortality. This increased risk is partly driven by an impaired glucose metabolism, which is influenced by elevated cortisol levels and a disrupted circadian cortisol rhythm. The aim of this study was to improve the understanding of the glucose metabolism in patients with CS, utilizing continuous glucose monitoring (CGM) before and after surgical intervention.

Methods: This was a prospective, cross-sectional and longitudinal study. We included ten adult patients (9 female, 1 male) with CS (6 pituitary, 4 adrenal), and an HbA1c < 7.0 %. The data collection with CGM was conducted before surgical intervention and 3 and 6 months postoperatively. At 3 months, all patients received a median hydrocortisone dose of 32.5 mg (IQR 15.0), which was reduced to 20.0 mg (IQR 10.0) at 6 months. At each time point continuously measured glucose concentrations, fasting glucose and insulin concentrations, HBA1c and BMI were compared.

Results: At baseline, patients had a median age of 36.7 years (26-50) and a median BMI of 33.2 kg/m² (23.8-51.7). Preliminary data indicate that the median (IQR) nocturnal glucose concentration was significantly higher at baseline (117.2mg/dl (26.55)) compared to three and six months post-surgery (99.53 mg/dl (23.63), P = 0.022; 100.77 mg/dl (10.78), P = 0.022). No significant differences were observed during the daytime. The median time (IQR) spent in the mild hyperglycemia range (140-180 mg/dl) per night (10pm to 6am) was significantly longer at baseline (13.70 % (20.65), 3 hours and 17 minutes), compared to three and six months post-surgery (4.71 % (9.76), 1 hour and 8 minutes, P = 0.01; 3.89 % (8.35), 56 minutes, P = 0.044). Fasting glucose and insulin concentrations, HbA1c or BMI did not change significantly.

Conclusion: These preliminary findings suggest that surgical therapy in patients with CS leads to significant improvements in nocturnal glucose control, with stabilization occurring within three to six months post-surgery. The results highlight the potential for CGM to offer valuable insights into glucose metabolism in CS, particularly during the night. Furthermore, CGM could contribute to the early detection of post-surgical relapse by identifying changes in glucose levels that may reflect a recurrence of the condition.

Keywords: Cushing’s syndrome, continuous glucose monitoring, CGM, glucose, circadian.