Citations

Abstract Health-related quality of life (HQOL) is a concept that aims to understand the totality of an individual’s experience of their disease state. This can include the physical, psychosocial, emotional, and psychological effects of a disease state. A complex and multifactorial concept, HQOL can be challenging to measure accurately and reliably. Thyroid eye disease (TED), as a multifaceted physically debilitating and facial disfiguring disorder, presents unique challenges and opportunities in the measurement of HQOL. Multiple distinct tools have been developed for this purpose, each has been constructed, assessed, and utilized. This discussion surveys the landscape of TED-related QOL measurement and presents challenges for the future. Clinicians and clinical researchers should implement TED-related QOL measurement as part of routine TED care and as a primary outcome in TED clinical trials. We recommend utilizing the Graves’ ophthalmopathy (GO)-QOL routinely in clinical practice and as a primary outcome in TED clinical trials. If the GO-QOL is too time-consuming or in mild TED, a faster alternative is the TED-QOL.

Abstract Context Maternally inherited STX16 deletions that cause loss of methylation at GNAS exon A/B and thereby reduce Gsα expression are the most frequent cause of autosomal dominant pseudohypoparathyroidism type Ib (AD-PHP1B). Early identification of these disease-causing variants in the children of affected and unaffected female carriers would prompt treatment with calcium and calcitriol once parathyroid hormone (PTH) levels increase, thereby preventing hypocalcemia and associated complications. Objective This study aimed to determine when PTH and calcium abnormalities develop after birth if a STX16 deletion is inherited maternally. Methods Forty-four children of affected (n = 7) or unaffected (n = 7) females with a STX16 deletion were investigated for the presence of these variants. If a deletion was identified, measurement of PTH, calcium, phosphate, and thyrotropin (TSH) was advised. Results The STX16 deletion that causes AD-PHP1B was identified in 25 children. Pretreatment laboratory results were available for 19 of those cases. Elevated PTH levels were detected by 2 years of age, and these were progressively higher if laboratory testing was first performed after establishing the genetic defect later in life. Total serum calcium levels remained within normal limits until about 5 years of age. TSH levels showed no consistent rise over time. Conclusion Establishing whether a STX16 deletion is inherited from a female carrier of a disease-causing variant rapidly establishes the diagnosis of AD-PHP1B. Several years before overt hypocalcemia developed, PTH levels increased, thereby establishing the onset of PTH resistance. Our findings provide diagnostic guidance and when treatment with calcium and calcitriol should be considered in order to prevent hypocalcemia and associated sequelae.

Purpose: Thyroid eye disease (TED) or Graves’ orbitopathy starts with an active inflammatory stage (active disease) followed by resolution of inflammation and progression to a fibrotic, inactive stage. In our practice, we have encountered cases that have not had active disease despite presence of fibrotic sequelae and disease progression. We aim to delineate the clinical characteristic of this unique group of patients. Methods: We conducted a single-center (Mayo Clinic Rochester) retrospective chart review of TED patients who throughout the course of their disease had only evidence for inactive TED, defined as clinical activity score <3. Results: Median age in the cohort (n = 19) was 54 years (IQR 47–61). 58% had a prior diagnosis of Graves’ disease (GD) before referral. 80% (n = 15) were euthyroid at the time of TED onset (median thyroid-stimulating hormone 1.7 mIU/L). The most common finding was diplopia (100%, n = 19) followed by proptosis (63%, n = 12). Interestingly the disease was asymmetric in 42% of cases. Overall median clinical activity score on presentation was 1 (IQR 0-1). Severity wise, 85% (n = 16) of patients were classified as moderate-to-severe during follow up. Orbital decompression was performed in only 1 case, while extraocular muscle surgery was performed in 13 cases. Conclusions: Quiet TED is a subgroup of TED patients that defies the classic disease paradigm. It presents primarily with diplopia and proptosis. Further evaluation of this group might identify useful insights in TED pathophysiology and help optimize therapeutic choices.

AbstractObjectivesLong-term follow-up is important for determining performance characteristics of thyroid fine-needle aspiration (FNA).MethodsHistologic or 3 or more years of clinical follow-up was used to calculate performance characteristics of thyroid FNA before and after implementation of The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC). The impact of noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) classification was also investigated.ResultsFollow-up was obtained for 1,277/1,134 and 1,616/1,393 aspirates/patients (median clinical follow-up, 9.9 and 4.4 years, pre- and post-TBSRTC, respectively). Nondiagnostic, suspicious for follicular neoplasm, and suspicious for malignancy (SFM) diagnoses decreased and benign diagnoses increased post-TBSRTC, while atypical rate remained less than 1%. Negative predictive value for benign nodules and positive predictive value (PPV) for SFM increased significantly. Eleven nodules were reclassified as NIFTP, slightly decreasing PPV/risk of malignancy (ROM).ConclusionsAppropriate ROM for thyroid FNA can be achieved through application of TBSRTC terminology with minimal use of atypical category.

The characteristics of pulsatile insulin secretion are important determinants of type 2 diabetes pathophysiology, but they are understudied due to the difficulties in measuring pulsatile insulin secretion noninvasively. Deconvolution of either peripheral C-peptide or insulin concentrations offers an appealing alternative to hepatic vein catheterization. However, to do so, there are a series of methodological challenges to overcome. C-peptide has a relatively long half-life and accumulates in the circulation. On the other hand, peripheral insulin concentrations reflect relatively fast clearance and hepatic extraction as it leaves the portal circulation to enter the systemic circulation. We propose a method based on nonparametric stochastic deconvolution of C-peptide concentrations, using individually determined C-peptide kinetics, to overcome these limitations. The use of C-peptide (instead of insulin) concentrations allows estimation of portal (and not post-hepatic) insulin pulses, whereas nonparametric stochastic deconvolution allows evaluation of pulsatile signals without any a priori assumptions of pulse shape and occurrence. The only assumption required is the degree of smoothness of the (unknown) secretion rate. We tested this method first on simulated data and then on 29 nondiabetic subjects studied during euglycemia and hyperglycemia and compared our estimates with the profiles obtained from hepatic vein insulin concentrations. This method produced satisfactory results both in the ability to fit the data and in providing reliable estimates of pulsatile secretion, in agreement with hepatic vein measurements. In conclusion, the proposed method enables reliable and noninvasive measurement of pulsatile insulin secretion. Future studies will be needed to validate this method in people with type 2 diabetes.

Abstract BACKGROUND Previously defined thresholds for total testosterone (TT) concentrations to screen for androgen-producing tumors (APTs) have used RIA, which can be less accurate in women. We aimed to define diagnostic thresholds to screen for APTs or postmenopausal pathologic hyperandrogenism using TT concentrations measured by Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS). METHODS We performed a retrospective cohort study on all women with TT ≥3.5 nmol/L and all postmenopausal women presenting with hyperandrogenism between 2004 and 2014 at the Mayo Clinic in Rochester, MN. RESULTS Of the 369 women with TT ≥3.5 nmol/L, 89 were included and subdivided into 3 groups based on their clinical diagnosis [21 (24%), APT; 16 (18%), postmenopausal pathologic hyperandrogenism; 52 (58%), polycystic ovary syndrome]. The source of the APT was more frequently ovarian (81%, n = 17) than adrenal (19%, n = 4). The diagnostic threshold using ROC analysis for TT to identify APT in women with severe biochemical hyperandrogenemia was ≥5.1 nmol/L (sensitivity, 90%; specificity, 81%). In a second analysis of a cohort of postmenopausal women only presenting with symptoms or signs of hyperandrogenism, median TT was significantly higher in the postmenopausal pathologic hyperandrogenism group (APT and ovarian hyperthecosis) vs the idiopathic hyperandrogenism group (4.9 vs 0.8 nmol/L; P &lt; 0.01). In postmenopausal women, the diagnostic threshold for pathologic hyperandrogenism was TT ≥2.2 nmol/L (sensitivity, 100%; specificity, 86%). CONCLUSIONS The diagnostic threshold for TT concentration as measured by LC-MS/MS to identify APT in women with biochemical severe hyperandrogenemia was TT ≥5.1 nmol/L. In postmenopausal women, the diagnostic threshold for pathologic hyperandrogenism was lower (TT ≥2.2 nmol/L).

Abstract Context Abnormal glucagon concentrations contribute to hyperglycemia, but the mechanisms of α-cell dysfunction in prediabetes are unclear. Objective We sought to determine the relative contributions of insulin secretion and action to α-cell dysfunction in nondiabetic participants across the spectrum of glucose tolerance. Design This was a cross-sectional study. A subset of participants (n = 120) was studied in the presence and absence of free fatty acid (FFA) elevation, achieved by infusion of Intralipid (Baxter Healthcare, Deerfield, IL) plus heparin, to cause insulin resistance. Setting An inpatient clinical research unit at an academic medical center. Participants A total of 310 nondiabetic persons participated in this study. Interventions Participants underwent a seven-sample oral glucose tolerance test. Subsequently, 120 participants were studied on two occasions. On one day, infusion of Intralipid plus heparin raised FFA. On the other day, participants received glycerol as a control. Main Outcome Measure(s) We examined the relationship of glucagon concentration with indices of insulin action after adjusting for the effects of age, sex, and weight. Subsequently, we sought to determine whether an acute decrease in insulin action, produced by FFA elevation, altered glucagon concentrations in nondiabetic participants. Results Fasting glucagon concentrations correlated positively with fasting insulin and C-peptide concentrations and inversely with insulin action. Fasting glucagon was not associated with any index of β-cell function in response to an oral challenge. As expected, FFA elevation decreased insulin action and also raised glucagon concentrations. Conclusions In nondiabetic participants, glucagon secretion was altered by changes in insulin action.

Background: Glucose variability (GV) has been increasingly (or more extensively) studied in patients with type 1 diabetes (T1D) in the ambulatory setting; limited data exist on GV in hospitalized patients with T1D. Materials and Methods: Retrospective single center cohort study, we analyzed in-hospital glucose measurements to assess GV in 736 hospitalized patients in different units over a consecutive 5-year period of time. GV was assessed by mean blood glucose (BG), Average daily risk range (ADRR), high BG index, and low BG index. To place our findings in context, we conducted a systematic review using Cochrane collaboration methodology to critically analyze current published literature on GV in hospitalized T1D patients. Results: Overall, glycemic control was suboptimal with mean BG 183 ± 51.5 mg/dL and mean ADRR 35 with only 16% patients being categorized as low risk (ADRR <20) for hypo or hyperglycemia. Patients admitted in medical units had mean BG of 194.4 ± 42.8 mg/dL (95% CI = 101.2–346.6) and ADRR of 39.4 ± 16 (95% CI = 1.3–118.7), which were higher than the patients admitted in the surgical units (mean BG 168.1 ± 35.7 (95% CI = 74.8–301.8) and mean ADRR (28.8 ± 13.1 [95% CI = 0.3–93.1]). For the systematic review, initial search yielded 2336 studies for screening, however, none of them had data specific for T1D. Conclusion: GV is high in hospitalized T1D patients admitted at our tertiary care center. Review of the literature shows paucity of data regarding GV in hospitalized patients with T1D.

Aims To compare the performance of population‐based kinetics with that of directly measured C‐peptide kinetics when used to calculate β‐cell responsivity indices, and to study people with and without acute insulin resistance to ensure that population‐based kinetics apply to all conditions where β‐cell function is measured. Methods Somatostatin was used to inhibit endogenous insulin secretion in 56 people without diabetes. Subsequently, a C‐peptide bolus was administered and the changing concentrations were used to calculate individual kinetic measures of C‐peptide clearance. In addition, the participants were studied on 2 occasions in random order using an oral glucose tolerance test (OGTT). On one occasion, free fatty acid elevation, to cause insulin resistance, was achieved by infusion of Intralipid + heparin. The Disposition Index (DI) was then estimated by the oral minimal model using either population‐based or individual C‐peptide kinetics. Results There were marked differences in the exchange variables ( k 12 and k 21 ) of the model describing C‐peptide kinetics, but smaller differences in the fractional clearance; that is, the irreversible loss from the accessible compartment ( k 01 ), obtained from population‐based estimates compared with experimental measurement. Because it is predominantly influenced by k 01 , DI estimated using individual kinetics correlated well with DI estimated using population‐based kinetics. Conclusions These data support the use of population‐based measures of C‐peptide kinetics to estimate β‐cell function during an OGTT.