Prevalence of Nelson's syndrome after bilateral adrenalectomy in patients with cushing's disease: a systematic review and meta-analysis.

PURPOSE: Bilateral adrenalectomy (BA) still plays an important role in the management of Cushing's disease (CD). Nelson's syndrome (NS) is a severe complication of BA, but conflicting data on its prevalence and predicting factors have been reported. The aim of this study was to determine the prevalence of NS, and identify factors associated with its development. DATA SOURCES: Systematic literature search in four databases. STUDY SELECTION: Observational studies reporting the prevalence of NS after BA in adult patients with CD. DATA EXTRACTION: Data extraction and risk of bias assessment were performed by three independent investigators. DATA SYNTHESIS: Thirty-six studies, with a total of 1316 CD patients treated with BA, were included for the primary outcome. Pooled prevalence of NS was 26% (95% CI 22-31%), with moderate to high heterogeneity (I2 67%, P < 0.01). The time from BA to NS varied from 2 months to 39 years. The prevalence of NS in the most recently published studies, where magnet resonance imaging was used, was 38% (95% CI 27-50%). The prevalence of treatment for NS was 21% (95% CI 18-26%). Relative risk for NS was not significantly affected by prior pituitary radiotherapy [0.9 (95% CI 0.5-1.6)] or pituitary surgery [0.6 (95% CI 0.4-1.0)]. CONCLUSIONS: Every fourth patient with CD treated with BA develops NS, and every fifth patient requires pituitary-specific treatment. The risk of NS may persist for up to four decades after BA. Life-long follow-up is essential for early detection and adequate treatment of NS.

Excess Morbidity Persists in Patients With Cushing's Disease During Long-term Remission: A Swedish Nationwide Study.

CONTEXT: Whether multisystem morbidity in Cushing's disease (CD) remains elevated during long-term remission is still undetermined. OBJECTIVE: To investigate comorbidities in patients with CD. DESIGN, SETTING, AND PATIENTS: A retrospective, nationwide study of patients with CD identified in the Swedish National Patient Register between 1987 and 2013. Individual medical records were reviewed to verify diagnosis and remission status. MAIN OUTCOMES: Standardized incidence ratios (SIRs) with 95% confidence intervals (CIs) were calculated by using the Swedish general population as reference. Comorbidities were investigated during three different time periods: (i) during the 3 years before diagnosis, (ii) from diagnosis to 1 year after remission, and (iii) during long-term remission. RESULTS: We included 502 patients with confirmed CD, of whom 419 were in remission for a median of 10 (interquartile range 4 to 21) years. SIRs (95% CI) for myocardial infarction (4.4; 1.2 to 11.4), fractures (4.9; 2.7 to 8.3), and deep vein thrombosis (13.8; 3.8 to 35.3) were increased during the 3-year period before diagnosis. From diagnosis until 1 year after remission, SIRs (95% CI were increased for thromboembolism (18.3; 7.9 to 36.0), stroke (4.9; 1.3 to 12.5), and sepsis (13.6; 3.7 to 34.8). SIRs for thromboembolism (4.9; 2.6 to 8.4), stroke (3.1; 1.8 to 4.9), and sepsis (6.0; 3.1 to 10.6) remained increased during long-term remission. CONCLUSION: Patients with CD have an increased incidence of stroke, thromboembolism, and sepsis even after remission, emphasizing the importance of early identification and management of risk factors for these comorbidities during long-term follow-up.

Overall and Disease-Specific Mortality in Patients With Cushing Disease: A Swedish Nationwide Study.

CONTEXT: Whether patients with Cushing disease (CD) in remission have increased mortality is still debatable. OBJECTIVE: To study overall and disease-specific mortality and predictive factors in an unselected nationwide cohort of patients with CD. DESIGN, PATIENTS, AND METHODS: A retrospective study of patients diagnosed with CD, identified in the Swedish National Patient Registry between 1987 and 2013. Medical records were systematically reviewed to verify the diagnosis. Standardized mortality ratios (SMRs) with 95% CIs were calculated and Cox regression models were used to identify predictors of mortality. RESULTS: Of 502 identified patients with CD (n = 387 women; 77%), 419 (83%) were confirmed to be in remission. Mean age at diagnosis was 43 (SD, 16) years and median follow-up was 13 (interquartile range, 6 to 23) years. The observed number of deaths was 133 vs 54 expected, resulting in an overall SMR of 2.5 (95% CI, 2.1 to 2.9). The commonest cause of death was cardiovascular diseases (SMR, 3.3; 95% CI, 2.6 to 4.3). Excess mortality was also found associated with infections and suicide. For patients in remission, the SMR was 1.9 (95% CI, 1.5 to 2.3); bilateral adrenalectomy and glucocorticoid replacement therapy were independently associated with increased mortality, whereas GH replacement was associated with improved outcome. CONCLUSION: Findings from this large nationwide study indicate that patients with CD have excess mortality. The findings illustrate the importance of achieving remission and continued active surveillance, along with adequate hormone replacement and evaluation of cardiovascular risk and mental health.

The incidence of Cushing's disease: a nationwide Swedish study.

BACKGROUND: Studies on the incidence of Cushing's disease (CD) are few and usually limited by a small number of patients. The aim of this study was to assess the annual incidence in a nationwide cohort of patients with presumed CD in Sweden. METHODS: Patients registered with a diagnostic code for Cushing's syndrome (CS) or CD, between 1987 and 2013 were identified in the Swedish National Patient Registry. The CD diagnosis was validated by reviewing clinical, biochemical, imaging, and histopathological data. RESULTS: Of 1317 patients identified, 534 (41%) had confirmed CD. One-hundred-and-fifty-six (12%) patients had other forms of CS, 41 (3%) had probable but unconfirmed CD, and 334 (25%) had diagnoses unrelated to CS. The mean (95% confidence interval) annual incidence between 1987 and 2013 of confirmed CD was 1.6 (1.4-1.8) cases per million. 1987-1995, 1996-2004, and 2005-2013, the mean annual incidence was 1.5 (1.1-1.8), 1.4 (1.0-1.7) and 2.0 (1.7-2.3) cases per million, respectively. During the last time period the incidence was higher than during the first and second time periods (P < 0.05). CONCLUSION: The incidence of CD in Sweden (1.6 cases per million) is in agreement with most previous reports. A higher incidence between 2005 and 2013 compared to 1987-2004 was noticed. Whether this reflects a truly increased incidence of the disease, or simply an increased awareness, earlier recognition, and earlier diagnosis can, however, not be answered. This study also illustrates the importance of validation of the diagnosis of CD in epidemiological research.