Aims/hypothesis: The prevalence and mechanisms of diabetes in hereditary haemochromatosis are not known. We therefore measured glucose tolerance, insulin secretory capacity and insulin sensitivity in adults with haemochromatosis.Subjects and methods: Subjects recruited from referrals to a haemochromatosis clinic underwent OGTT and frequently sampled IVGTT. A chart review of former clinic patients was also performed. Results: The prevalence of diabetes (23%) and IGT (30%) was increased in haemochromatosis compared with matched control subjects (0% diabetes and 14% IGT). Subjects with haemochromatosis and diabetes were overweight (14%) or obese (86%). The prevalence of diabetes, as determined by chart review of fasting glucose values, in subjects who had haemochromatosis and were in the 40-79 years age range was 26%. Overall, patients with haemochromatosis and control subjects had similar values for acute insulin response to glucose and insulin sensitivity. However, patients with haemochromatosis and IGT had a 68% decrease in acute insulin response to glucose (p<0.02) compared with those with NGT. They were not insulin-resistant, exhibiting instead a 62% increase in insulin sensitivity (NS). Haemochromatosis subjects with diabetes exhibited further declines in acute insulin response to glucose, insulin resistance, or both.Conclusions/interpretation: Diabetes and IGT are common in haemochromatosis, justifying screening for diabetes and therapeutic phlebotomy. The major abnormality associated with IGT is decreased insulin secretory capacity. Diabetes is usually associated with obesity and concomitant insulin resistance.

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Background Dyslipidemia has been documented in youth with type 2 diabetes. There is a paucity of studies examining dyslipidemia over time in youth with type 2 diabetes and associated risk factors. Objective To evaluate lipids at baseline and follow‐up and associated risk factors in youth with type 2 diabetes. Methods We studied 212 youth with type 2 diabetes at baseline and after an average of 7 years of follow‐up in the SEARCH for Diabetes in Youth Study. Abnormal lipids were defined as high‐density lipoprotein cholesterol (HDL‐C) < 35, low‐density lipoprotein cholesterol (LDL‐C) > 100, or triglycerides >150 (all mg/dl). We evaluated participants for progression to abnormal lipids (normal lipids at baseline and abnormal at follow‐up), regression (abnormal lipids at baseline and normal at follow‐up), stable normal, and stable abnormal lipids over time for HDL‐C, LDL‐C, and triglycerides. Associations between hemoglobin A1c (HbA1c) and adiposity over time (area under the curve [AUC]) with progression and stable abnormal lipids were evaluated. Results HDL‐C progressed, regressed, was stable normal, and stable abnormal in 12.3%, 11.3%, 62.3%, and 14.2% of participants, respectively. Corresponding LDL‐C percentages were 15.6%, 12.7%, 42.9%, and 28.8% and triglycerides were 17.5%, 10.8%, 55.7%, and 16.0%. Each 1% increase in HbA1c AUC was associated with a 13% higher risk of progression and stable abnormal triglycerides and a 20% higher risk of progression and stable abnormal LDL‐C. Higher adiposity AUC was marginally (p = 0.049) associated with abnormal HDL‐C. Conclusions Progression and stable abnormal LDL‐C and triglycerides occur in youth with type 2 diabetes and are associated with higher HbA1c.

Context. A currently unsolved question in supernova (SN) research is the origin of stripped-envelope supernovae (SESNe). Such SNe lack spectral signatures of hydrogen (Type Ib), or hydrogen and helium (Type Ic), indicating that the outer stellar layers have been stripped during their evolution. The mechanism for this is not well understood, and to disentangle the different scenarios’ determination of nucleosynthesis yields from observed spectra can be attempted. However, the interpretation of observations depends on the adopted spectral models. A previously missing ingredient in these is the inclusion of molecular effects, which can be significant. Aims. We aim to investigate how the molecular chemistry in SESNe affect physical conditions and optical spectra, and produce ro-vibrational emission in the mid-infrared (MIR). We also aim to assess the diagnostic potential of observations of such MIR emission with JWST. Methods. We coupled a chemical kinetic network including carbon, oxygen, silicon, and sulfur-bearing molecules into the nonlocal thermal equilibrium (NLTE) spectral synthesis code SUMO. We let four species – CO, SiO, SiS, and SO – participate in NLTE cooling of the gas to achieve self-consistency between the molecule formation and the temperature. We applied the new framework to model the spectrum of a Type Ic SN in the 100–600 days time range. Results. Molecules are predicted to form in SESN ejecta in significant quantities (typical mass 10−3 M⊙) throughout the 100–600 days interval. The impact on the temperature and optical emission depends on the density of the oxygen zones and varies with epoch. For example, the [O I] 6300, 6364 feature can be quenched by molecules from 200 to 450 days depending on density. The MIR predictions show strong emission in the fundamental bands of CO, SiO, and SiS, and in the CO and SiO overtones. Conclusions. Type Ibc SN ejecta have a rich chemistry and considering the effect of molecules is important for modeling the temperature and atomic emission in the nebular phase. Observations of SESNe with JWST hold promise to provide the first detections of SiS and SO, and to give information on zone masses and densities of the ejecta. Combined optical, near-infrared, and MIR observations can break degeneracies and achieve a more complete picture of the nucleosynthesis, chemistry, and origin of Type Ibc SNe.

Limited information exists regarding the evolution of dyslipidemia in youth with type 2 diabetes (T2D). Understanding dyslipidemia risk factors may influence treatment. We studied 212 youth with T2D not on lipid lowering therapy (68% female, 43% non-Hispanic black, mean age 14.9±2.7y at baseline, mean follow-up 7.0±2.0y). Dyslipidemia was defined as HDL-C&lt;35mg/dL, LDL-C&gt;100mg/dL, or triglycerides (TG)&gt;150mg/dL. Progression was defined as normal lipids at baseline, dyslipidemia at follow-up; regression as dyslipidemia at baseline, normal at follow-up; stable abnormal as dyslipidemia at both; stable normal as normal at both. Associations of A1c and abdominal adiposity (waist to height ratio, WHtR) over time (area under the curve, AUC) with progression and stable abnormal were examined and relative risks estimated. HDL-C progressed, regressed, was stable normal and stable abnormal in 12%, 11%, 62%, and 14%, respectively. Corresponding LDL-C values were 16%, 13%, 43% and 29%; TG were 17%, 11%, 56% and 16%. Each 1% increase in A1c AUC was associated with 13% higher risk of TG&gt;150mg/dL and 22% higher risk of LDL-C&gt;100mg/dL, after adjusting for WHtR (Table). There were no significant associations with WHtR. In youth with T2D, 33% and 45% had progression or stable dyslipidemia of TG and LDL-C, respectively. Higher A1c over time is associated with worse TG and LDL-C, highlighting the importance of glycemic control. Disclosure R.P. Brady: None. A.S. Shah: None. E.T. Jensen: None. J.M. Stafford: None. R. Dagostino: Consultant; Self; Amgen, AstraZeneca, Celgene, Daiichi Sankyo. L.M. Dolan: None. L.M. Knight: None. G. Imperatore: None. C.B. Turley: None. A.D. Liese: None. E.M. Urbina: None. J.M. Lawrence: None. C. Pihoker: None. S.M. Marcovina: None. D. Dabelea: None. Funding Centers for Disease Control and Prevention (1U18DP006131, U18DP006133, U18DP006134, U18DP006136, U18DP006138, U18DP006139); National Institutes of Health (1UC4DK108173)

Aims. Celiac disease (CD) in adults with type 1 diabetes has been associated with increased cardiovascular risk and the earlier occurrence of diabetes-associated complications. In the Search for Diabetes in Youth study, we aimed to assess the frequency of CD and the potential for undiagnosed CD among youth with childhood onset type 1 diabetes. In addition, we assessed the burden of cardiovascular risk factors and diabetes-associated complications in youth with type 1 diabetes by CD status and IgA tissue transglutaminase autoantibody (tTGA) levels. Methods. 2,444 youths with type 1 diabetes completed a CD questionnaire and underwent tTGA testing. Integrating the celiac disease questionnaire and tTGA results for this cross-sectional analysis, participants were categorized as follows: (1) reported CD; (2) seropositive for CD (no reported CD and seropositive tTGA); and (3) type 1 diabetes only (comparison group: no reported CD and seronegative tTGA). Subanalyses were performed on those with no reported CD and tTGA ≥10x ULN, designated potentially undiagnosed CD. Cardiovascular risk factors and diabetes-associated complications were evaluated by CD status and tTGA levels utilizing a Poisson model to estimate relative risk. Results. Reported CD in youths with type 1 diabetes was 7%. Seropositivity for tTGA with no reported CD was present in 4%, and 1.2% had potentially undiagnosed CD. Youths with potentially undiagnosed CD had a 2.69x higher risk of diabetic retinopathy than comparison group. In addition, CD with tTGA <0.05 (controlled CD) was associated with lower HbA1c. Conclusions. Undiagnosed CD is likely present in youths with type 1 diabetes and potentially undiagnosed CD is associated with a higher risk of diabetic retinopathy. These findings indicate the importance of routine screening for CD in type 1 diabetes in youths.

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