New research was presented at AACE 2019, the American Association of Clinical Endocrinologists Annual Scientific & Clinical Congress, from April 34-28 in Los Angeles. The features below highlight some of the studies that emerged from the conference.
Trabecular Bone Score by Hemodialysis Status
Prior research suggests that bone mineral density (BMD) is not as useful in predicting fracture risk in patients on permanent hemodialysis (HD) as it is in the general population. And while trabecular bone score (TBS) has been shown to be an independent risk factor for fracture in the general population, the value of TBS in HD patients remains unclear. Researchers conducted a study to assess BMD and lumbar spine (LS) TBS in HD patients compared with those of people with normal kidney function matched for age, gender, and LS BMD. TBS was significantly lower in HD patients, independent of BMD. Lower TBS reflected changes and damage in bone microarhitecture that occur in patients on permanent HD and could explain the increased risk of fracture at these patients. The absolute 10-year major and hip osteoporotic fracture risk was significantly increased in HD patients compared with controls due to lower femoral neck BMD.
Precursors of Adrenal Tumors & Cushing’s Syndrome
Systematic studies of the clinical applicability of serum steroid precursors measured with currently available assays are lacking. To evaluate the diagnostic value and clinical utility of such precursors in a prospective cohort of patients with adrenal tumors and Cushing’s syndrome (CS), researchers measured 11-deoxycortisol (DCORT), 17-Hydroxypregnenolone (17OHPreg), 17-hydroxyprogesterone (17OHProg), Pregnenolone (PREG), Androstenedione (ANDRO), Dehydroepiandrostenedione sulfate (DHEAS), and cortisol in adults with any type of CS or adrenal mass. Participants with adrenocortical carcinoma (ACC) had 2.5 to 12 times higher concentrations of 17OHPreg, 17OHProg, DHEAS, PREG, ANDRO, and DCORT than those with other adrenal tumors. A multivariable model of 17OHPreg, 17OHProg, and DCORT accurately predicted ACC. 17OHPreg and DHEAS were lowest and DCORT was highest in patients with CS when compared with those with mild autonomous cortisol secretion (MACS) and non-functioning adrenal tumors (NFAT). In patients with MACS versus NFAT only, 17OHPreg was a significant predictor of MACS in a multivariable model. Patients with adrenocorticotropic hormone (ACTH)-independent CS had lower 17OHPreg and DHEAS than those with ACTH-dependent CS. In patients with ACTH-dependent CS, those with ectopic CS had higher DCORT and 17OHProg, with DCORT significantly predicting ectopic CS, even after correcting for cortisol concentrations.
Detecting Parathyroid Adenomas
Research is limited comparing the accuracy of 18F-fluorocholine positron-emission tomography/CT (PET) with that of both technetium sestamibi single photon emission computed tomography (MIBI) and high-resolution neck ultrasound (US) in the preoperative detection of parathyroid adenoma (PA) in patients with primary hyperparathyroidism (PHPT). To do so, study investigators considered the finding of an enlarged/hyperfunctioning parathyroid gland in at least in two of three imaging techniques among patients with PHPT who underwent US, MIBI, and PET. Detection rates for PA were 73% for PET, 40% for MIBI, and 60% for US. Approximate concordant positive results were 23% for PET-MIBI, 47% for PET-US, and 30% for MIBI-US. Approximate concordant negative results were 10% for PET-MIBI, 13% for PET-US, and 275 for MIBI-US 26.7%. Among the 90% of patients who recovered after surgery, PET detected PA in 100%, while MIBI and US found PA in 22% and 67%, respectively.
Assessing a 24-Hour Wearable Insulin-Delivery Device
With few previous studies evaluating the impact of a 24-hour wearable basal-bolus insulin-delivery device on clinical outcomes, researchers evaluated change in A1C, insulin total daily dose (TDD), concomitant non-insulin glucose-lowering medications (NIGLM), reported hypoglycemia, and weight among patients of a large, specialized diabetes center who exceeded glycemic targets; were prescribed basal-bolus multiple daily injection insulin (MDI), basal insulin, premix insulin, or no insulin at baseline; and were changed to the wearable device. After a mean of 5 months of wearable device use, all patients and cohorts experienced reductions in A1C, including changes of -1.5 for all patients, -1.5 for the MDI group, -1.3 for the basal insulin group, -0.6 for the premix group, and -3.3 for the insulin naïve group. Across all patients previously prescribed insulin, insulin TDD decreased from 63 to 54 units per day.
Diabetes & Long-Term Fracture Risk
Although older adults with type 2 diabetes are at increased risk for fracture when compared with those without the condition, the former tend to have normal-to-high bone mineral density (BMD). Knowledge of imminent or short-term fracture risk in those with T2D is lacking. For a study, the association of T2D with fracture incidence over short- and long-term risk of fracture in a community-based cohort was evaluated. Incident fractures excluded finger, toe, skull, face, and pathologic fractures. The study authors used repeated measures analyses to estimate hazard ratios (HRs, 95% CIs) for the association between T2D, T2D medication use, and T2D duration and incident fracture, adjusted for age, gender, height, and weight. Follow-up time was calculated from baseline to the first of: fracture, death, loss, or end of follow-up in 2009. Among women, the cumulative incidence of fracture was 37% for those with T2D, compared with 30% for those without T2D. Among men, these rates were 11% and 16%, respectively. T2D was associated with 1-year fracture risk in women (HR, 2.23) but not in men. Among all participants, longer duration of T2D (HR, 1.28 per 5 years) and any T2D medication use (HR, 1.70) increased 2-year fracture risk. Associations between T2D and long-term incidence of fracture were not significant. The researchers note that competing risk of death may have resulted in them underestimating associations with long-term fracture.