Rachel K Crowley, Beverly Hughes, Joanna Gray, Theresa McCarthy, Susan Hughes, Cedric H L Shackleton, Nicola Crabtree, Peter Nightingale, Paul M Stewart and Jeremy W Tomlinson
Dysregulation of enzymes that control local tissue steroid metabolism has been implicated in the pathogenesis of obesity and insulin resistance; however, longitudinal changes in glucocorticoid metabolism have not been investigated. This study was performed to evaluate the role of glucocorticoid metabolism in the development of insulin resistance and obesity and to identify biomarkers for future development of metabolic disease.
This was a prospective longitudinal observation study conducted over 5 years.
A 24-h collection was used to serially analyze urinary glucocorticoid and mineralocorticoid metabolites in 57 obese and overweight patients with no prior diagnosis of diabetes mellitus, recruited from the community.
Baseline higher 5α-reductase (5αR) activity, but not 11β-hydroxysteroid dehydrogenase type 1 activity, was predictive of increased fasting insulin at final visit (11.4 compared with 7.4 mU/l in subjects with lower 5αR activity, P<0.05), area under the curve insulin response to oral glucose tolerance test (176.7 compared with 89.1 mU/l.h, P<0.01), and homeostasis model assessment (HOMA2-IR; 1.3 compared with 0.8, P<0.01). Higher total glucocorticoid production was associated with abnormal glucose tolerance and increased BMI. During this study, systolic blood pressure increased (equivalent to ∼1 mmHg/year), as did plasma sodium levels; this evidence of increased mineralocorticoid activity was associated with increased aldosterone metabolites and decreased 11β-hydroxysteroid dehydrogenase type 2 activity.
Increased 5αR activity and glucocorticoid secretion rate over time are linked with the development of metabolic disease, and may represent targets for therapeutic intervention, which merits further study.
Irina Bancos, Fares Alahdab, Rachel K Crowley, Vasileios Chortis, Danae A Delivanis, Dana Erickson, Neena Natt, Massimo Terzolo, Wiebke Arlt, William F Young Jr and M Hassan Murad
Beneficial effects of adrenalectomy on cardiovascular risk factors in patients with subclinical Cushing’s syndrome (SCS) are uncertain. We sought to conduct a systematic review and meta-analysis with the following objectives: (i) determine the effect of adrenalectomy compared with conservative management on cardiovascular risk factors in patients with SCS and (ii) compare the effect of adrenalectomy on cardiovascular risk factors in patients with SCS vs those with a nonfunctioning (NF) adrenal tumor.
MEDLINE In-Process & Other Non-Indexed Citations, MEDLINE, EMBASE and Cochrane Central Register of Controlled Trial were searched on 17 November 2015. Reviewers extracted data and assessed methodological quality in duplicate.
We included 26 studies reporting on 584 patients with SCS and 457 patients with NF adrenal tumors. Studies used different definitions of SCS. Patients with SCS undergoing adrenalectomy demonstrated an overall improvement in cardiovascular risk factors (61% for hypertension, 52% for diabetes mellitus, 45% for obesity and 24% for dyslipidemia). When compared with conservative management, patients with SCS undergoing adrenalectomy experienced improvement in hypertension (RR 11, 95% CI: 4.3–27.8) and diabetes mellitus (RR 3.9, 95% CI: 1.5–9.9), but not dyslipidemia (RR 2.6, 95% CI: 0.97–7.2) or obesity (RR 3.4, 95% CI: 0.95–12). Patients with NF adrenal tumors experienced improvement in hypertension (21/54 patients); however, insufficient data exist for comparison to patients with SCS.
Available low-to-moderate-quality evidence from heterogeneous studies suggests a beneficial effect of adrenalectomy on cardiovascular risk factors in patients with SCS overall and compared with conservative management.
Conor P Woods, Nicola Argese, Matthew Chapman, Christopher Boot, Rachel Webster, Vijay Dabhi, Ashley B Grossman, Andrew A Toogood, Wiebke Arlt, Paul M Stewart, Rachel K Crowley and Jeremy W Tomlinson
Up to 3% of US and UK populations are prescribed glucocorticoids (GC). Suppression of the hypothalamo–pituitary–adrenal axis with the potential risk of adrenal crisis is a recognized complication of therapy. The 250 μg short Synacthen stimulation test (SST) is the most commonly used dynamic assessment to diagnose adrenal insufficiency. There are challenges to the use of the SST in routine clinical practice, including both the staff and time constraints and a significant recent increase in Synacthen cost.
We performed a retrospective analysis to determine the prevalence of adrenal suppression due to prescribed GCs and the utility of a morning serum cortisol for rapid assessment of adrenal reserve in the routine clinical setting.
In total, 2773 patients underwent 3603 SSTs in a large secondary/tertiary centre between 2008 and 2013 and 17.9% (n=496) failed the SST. Of 404 patients taking oral, topical, intranasal or inhaled GC therapy for non-endocrine conditions, 33.2% (n=134) had a subnormal SST response. In patients taking inhaled GCs without additional GC therapy, 20.5% (34/166) failed an SST and suppression of adrenal function increased in a dose-dependent fashion. Using receiver operating characteristic curve analysis in patients currently taking inhaled GCs, a basal cortisol ≥348 nmol/l provided 100% specificity for passing the SST; a cortisol value <34 nmol/l had 100% sensitivity for SST failure. Using these cut-offs, 50% (n=83) of SSTs performed on patients prescribed inhaled GCs were unnecessary.
Adrenal suppression due to GC treatment, particularly inhaled GCs, is common. A basal serum cortisol concentration has utility in helping determine which patients should undergo dynamic assessment of adrenal function.