The association of bone mineral density Z-score with the early postoperative remission and characteristics of bone mineral loss in patients with Cushing's disease: a retrospective study.

AIM: To investigate the association of bone mineral density (BMD) Z-scores with early-postoperative remission rate and clinical parameters in patients with Cushing's disease (CD). METHODS: We retrospectively evaluated the records of patients diagnosed with CD. After the exclusion of 230 patients, 87 CD patients were finally enrolled. BMD was determined by dual-energy x-ray absorptiometry (DXA) at the lumbar spine 1-4 (L1-4) and left femur. Early-postoperative remission was defined as a morning cortisol concentration on the first day after surgery of less than 5 µg/dL. The diagnosis of BMD "below the expected range for age" was defined as a Z-score≤-2.00 standard deviations. RESULTS: DXA results were not significantly associated with early postoperative remission. They also did not significantly differ between eugonadal and menopausal groups. Preoperative morning cortisol significantly negatively but weakly correlated with Z-score of the total femur, while preoperative adrenocorticotropic hormone/cortisol ratio positively but weakly correlated with DXA results of L1-4. CONCLUSION: The severity of bone loss was not significantly related to the failure of transsphenoidal surgery for Cushing's disease.

The association between insulin-like growth factor 1 levels within reference range and early postoperative remission rate in patients with Cushing's disease.

INTRODUCTION: The relationship between growth hormone (GH)/insulin-like growth factor 1 (IGF-1) and glucocorticoids (GC) was examined in various studies. Long-term GC treatment was shown to decrease GH concentration and, interestingly, to increase IGF-1 concentration. We performed a retrospective study in order to examine how preoperative IGF-1 concentrations vary within the reference range and if tertiles of age- and sex-adjusted normal IGF-1 are predictive for early postoperative remission in the patients with Cushing's Disease (CD). PATIENTS AND METHODS: Patients diagnosed with CD were retrospectively evaluated. After the exclusion of 67 patients, a final cohort of 250 CD patients were included. Age- and sex-adjusted normal IGF-1 levels were divided into tertiles (T1, T2 and T3). Early postoperative remission was defined as a nadir morning cortisol concentration measured within the first 3 consecutive days following surgery of less than 5 µg/dL (138 nmol/L). RESULTS: Early postoperative remission rate was the lowest in T1 and highest in T3; 49.1% (n = 28) versus 77.3% (n = 75), p = .001, respectively. Binary logistic regression analysis showed the remission rate in T3 was three times higher than that in T1 (p = .003). Cortisol and ACTH concentration were significantly higher and GH concentrations were significantly lower in T1 compared to those in the other two tertiles. CONCLUSIONS: As the first study evaluating the correlation between early postoperative remission rate in patients with CD and the tertiles of normal age- and sex-adjusted IGF-1 levels, we have shown that higher IGF-1 levels could predict better outcome in CD.