Urinary sphingolipids in adolescents and young adults with youth-onset diabetes.

BACKGROUND: This study evaluated urinary sphingolipids as a marker of diabetic kidney disease (DKD) in adolescents and young adults with youth-onset type 1 and type 2 diabetes. METHODS: A comprehensive panel of urinary sphingolipids, including sphingomyelin (SM), glucosylceramide (GC), ceramide (Cer), and lactosylceramide (LC) species, was performed in patients with youth-onset diabetes from the SEARCH for Diabetes in Youth cohort. Sphingolipid levels, normalized to urine creatinine, were compared in 57 adolescents and young adults with type 1 diabetes, 59 with type 2 diabetes, and 44 healthy controls. The association of sphingolipids with albumin-to-creatinine (ACR) ratio and estimated glomerular filtration rate (eGFR) was evaluated. RESULTS: The median age (interquartile range [IQR]) of participants was 23.1 years (20.9, 24.9) and the median duration of diabetes was 9.3 (8.5, 10.2) years. Urinary sphingolipid concentrations in patients with and without DKD (ACR ≥ 30 mg/g) were significantly elevated compared to healthy controls. There were no significant differences in sphingolipid levels between participants with type 1 and type 2 diabetes. In multivariable analysis, many sphingolipid species were positively correlated with ACR. Most significant associations were evident for the following species: C18 SM, C24:1 SM, C24:1 GC, and C24:1 Cer (all p < 0.001). Sphingolipid levels were not associated with eGFR. However, several interaction terms (diabetes type*sphingolipid) were significant, indicating diabetes type may modify the association of sphingolipids with eGFR. CONCLUSION: Urinary sphingolipids are elevated in adolescents and young adults with youth-onset diabetes and correlate with ACR. Urinary sphingolipids may therefore represent an early biomarker of DKD.

Short-term fasting lowers glucagon levels under euglycemic and hypoglycemic conditions in healthy humans.

Fasting is associated with increased susceptibility to hypoglycemia in people with type 1 diabetes, thereby making it a significant health risk. To date, the relationship between fasting and insulin-induced hypoglycemia has not been well characterized, so our objective was to determine whether insulin-independent factors, such as counterregulatory hormone responses, are adversely impacted by fasting in healthy control individuals. Counterregulatory responses to insulin-induced hypoglycemia were measured in 12 healthy people during 2 metabolic studies. During one study, participants ate breakfast and lunch, after which they underwent a 2-hour bout of insulin-induced hypoglycemia (FED). During the other study, participants remained fasted prior to hypoglycemia (FAST). As expected, hepatic glycogen concentrations were lower in FAST, and associated with diminished peak glucagon levels and reduced endogenous glucose production (EGP) during hypoglycemia. Accompanying lower EGP in FAST was a reduction in peripheral glucose utilization, and a resultant reduction in the amount of exogenous glucose required to maintain glycemia. These data suggest that whereas a fasting-induced lowering of glucose utilization could potentially delay the onset of insulin-induced hypoglycemia, subsequent reductions in glucagon levels and EGP are likely to encumber recovery from it. As a result of this diminished metabolic flexibility in response to fasting, susceptibility to hypoglycemia could be enhanced in patients with type 1 diabetes under similar conditions.

Increase in newly diagnosed type 1 diabetes in youth during the COVID-19 pandemic in the United States: A multi-center analysis.

BACKGROUND: An increase in newly diagnosed type 1 diabetes (T1D) has been posited during the COVID-19 pandemic, but data are conflicting. We aimed to determine trends in newly diagnosed T1D and severity of presentation at diagnosis for pediatric and adolescent patients during COVID-19 (2020) as compared to the previous year (2019) in a multi-center analysis across the United States. METHODS: This retrospective study from seven centers in the T1D Exchange Quality Improvement Collaborative (T1DX-QI) included data on new onset T1D diagnosis and proportion in DKA at diagnosis from January 1 to December 31, 2020, compared to the prior year. Chi-square tests were used to compare differences in patient characteristics during the pandemic period compared to the prior year. RESULTS: Across seven sites, there were 1399 newly diagnosed T1D patients in 2020, compared to 1277 in 2019 (p = 0.007). A greater proportion of newly diagnosed patients presented in DKA in 2020 compared to 2019 (599/1399(42.8%) vs. 493/1277(38.6%), p = 0.02), with a higher proportion presenting with severe DKA (p = 0.01) as characterized by a pH <7.1 and/or bicarbonate of <5 mmol/L. Monthly data trends demonstrated a higher number of new T1D diagnoses over the spring and summer months (March to September) of 2020 compared to 2019 (p < 0.001). CONCLUSIONS: We found an increase in newly diagnosed T1D and a greater proportion presenting in DKA at diagnosis during the COVID-19 pandemic compared to the prior year. Future longitudinal studies are needed to confirm these findings with population level data and determine the long-term impact of COVID-19 on diabetes trends.

Increased Prevalence of Beta-Cell Dysfunction despite Normal HbA1c in Youth and Young Adults with Turner Syndrome.

INTRODUCTION: Adult women with Turner syndrome (TS) have a high prevalence of diabetes and ß-cell dysfunction that increases morbidity and mortality, but it is unknown if there is ß-cell dysfunction present in youth with TS. This study aimed to determine the prevalence of ß-cell dysfunction in youth with TS and the impact of traditional therapies on insulin sensitivity (SI) and insulin secretion. METHODS: Cross-sectional, observational study recruited 60 girls with TS and 60 healthy controls (HC) matched on pubertal status. Each subject had a history, physical exam, and oral glucose tolerance test (OGTT). Oral glucose and c-peptide minimal modeling was used to determine ß-cell function. RESULTS: Twenty-one TS girls (35%) met criteria for prediabetes. Impaired fasting glucose was present in 18% of girls with TS and 3% HC (p value = 0.02). Impaired glucose tolerance was present in 23% of TS girls and 0% HC (p value <0.001). The hemoglobin A1c was not different between TS and HC (median 5%, p = 0.42). Youth with TS had significant reductions in SI, ß-cell responsivity (Φ), and disposition index (DI) compared to HC. These differences remained significant when controlling for body mass index z-score (p values: 0.0006, 0.002, <0.0001 for SI, Φ total, DI, respectively). CONCLUSIONS: ß-Cell dysfunction is present in youth with TS compared to controls. The presence of both reduced insulin secretion and SI suggest a unique TS-related glycemic phenotype. Based on the data from this study, we strongly suggest that providers employ serial OGTT to screen for glucose abnormalities in TS youth.

C-peptide enhances glucagon secretion in response to hyperinsulinemia under euglycemic and hypoglycemic conditions.

Several studies have associated the presence of residual insulin secretion capability (also referred to as being C-peptide positive) with lower risk of insulin-induced hypoglycemia in patients with type 1 diabetes (T1D), although the reason is unclear. We tested the hypothesis that C-peptide infusion would enhance glucagon secretion in response to hyperinsulinemia during euglycemic and hypoglycemic conditions in dogs (5 male/4 female). After a 2-hour basal period, an intravenous (IV) infusion of insulin was started, and dextrose was infused to maintain euglycemia for 2 hours. At the same time, an IV infusion of either saline (SAL) or C-peptide (CPEP) was started. After this euglycemic period, the insulin and SAL/CPEP infusions were continued for another 2 hours, but the glucose was allowed to fall to approximately 50 mg/dL. In response to euglycemic-hyperinsulinemia, glucagon secretion decreased in SAL but remained unchanged from the basal period in CPEP condition. During hypoglycemia, glucagon secretion in CPEP was 2 times higher than SAL, and this increased net hepatic glucose output and reduced the amount of exogenous glucose required to maintain glycemia. These data suggest that the presence of C-peptide during IV insulin infusion can preserve glucagon secretion during euglycemia and enhance it during hypoglycemia, which could explain why T1D patients with residual insulin secretion are less susceptible to hypoglycemia.

Liver glycogen-induced enhancements in hypoglycemic counterregulation require neuroglucopenia.

Iatrogenic hypoglycemia is a prominent barrier to achieving optimal glycemic control in patients with diabetes, in part due to dampened counterregulatory hormone responses. It has been demonstrated that elevated liver glycogen content can enhance these hormonal responses through signaling to the brain via afferent nerves, but the role that hypoglycemia in the brain plays in this liver glycogen effect remains unclear. During the first 4 h of each study, the liver glycogen content of dogs was increased by using an intraportal infusion of fructose to stimulate hepatic glucose uptake (HG; n = 13), or glycogen was maintained near fasting levels with a saline infusion (NG; n = 6). After a 2-h control period, during which the fructose/saline infusion was discontinued, insulin was infused intravenously for an additional 2 h to bring about systemic hypoglycemia in all animals, whereas brain euglycemia was maintained in a subset of the HG group by infusing glucose bilaterally into the carotid and vertebral arteries (HG-HeadEu; n = 7). Liver glycogen content was markedly elevated in the two HG groups (43 ± 4, 73 ± 3, and 75 ± 7 mg/g in NG, HG, and HG-HeadEu, respectively). During the hypoglycemic period, arterial plasma glucose levels were indistinguishable between groups (53 ± 2, 52 ± 1, and 51 ± 1 mg/dL, respectively), but jugular vein glucose levels were kept euglycemic (88 ± 5 mg/dL) only in the HG-HeadEu group. Glucagon and epinephrine responses to hypoglycemia were higher in HG compared with NG, whereas despite the increase in liver glycogen, neither increased above basal in HG-HeadEu. These data demonstrate that the enhanced counterregulatory hormone secretion that accompanies increased liver glycogen content requires hypoglycemia in the brain.NEW & NOTEWORTHY It is well known that iatrogenic hypoglycemia is a barrier to optimal glycemic regulation in patients with diabetes. Our data confirm that increasing liver glycogen content 75% above fasting levels enhances hormonal responses to insulin-induced hypoglycemia and demonstrate that this enhanced hormonal response does not occur in the absence of hypoglycemia in the brain. These data demonstrate that information from the liver regarding glycogen availability is integrated in the brain to optimize the counterregulatory response.

Readiness for transition to adult care in adolescents and young adults with Turner syndrome.

Objectives Turner syndrome (TS) is a complex and chronic medical condition that requires lifelong subspecialty care. Effective transition preparation is needed for successful transfer from pediatric to adult care in order to avoid lapses in medical care, explore health issues such as fertility, and prepare caregivers as adolescents take over responsibility for their own care. The objective of this study was to evaluate accuracy of knowledge of personal medical history and screening guidelines in adolescents and young adults (AYA) with TS. Methods This was a prospective cross-sectional study of 35 AYA with TS of ages 13-22 years recruited from a tertiary care center. AYA completed questionnaires on personal medical history, knowledge of screening guidelines for TS, and the Transition Readiness Assessment Questionnaire (TRAQ). Results Eighty percent of AYA with TS were 100% accurate in reporting their personal medical history. Only one-third of AYA with TS were accurate about knowing screening guidelines for individuals with TS. Accuracy about knowing screening guidelines was significantly associated with TRAQ sum scores (r = 0.45, p < 0.05). However, there was no association between knowledge of personal medical history and TRAQ sum scores. Conclusions Transition readiness skills, TS-specific knowledge, and accurate awareness of health-care recommendations are related, yet distinct, constructs. Understanding of one's personal medical history is not an adequate surrogate for transition readiness. Validated tools for general transition, like the TRAQ, can be used but need to be complemented by TS-specific assessments and content. Providers are encouraged to identify opportunities for clinical and educational interventions well in advance of starting transfer to adult care.

SGPL1 Deficiency: A Rare Cause of Primary Adrenal Insufficiency.

CONTEXT: Multiple autosomal recessive genes have been etiologically linked to primary adrenal insufficiency (PAI). Recently, sphingosine-1-phosphate lyase 1 (SGPL1) gene mutations were recognized as a cause of steroid-resistant nephrotic syndrome type 14 (NPHS14), a sphingolipidosis with multisystemic manifestations, including PAI. OBJECTIVE: To check if SGPL1 mutations are involved in the pathogenesis of PAI in patients who do not exhibit nephrotic syndrome. METHODS: Sequencing of the SGPL1 gene in 21 patients with familial glucocorticoid disease or triple A syndrome. RESULTS: We identified two missense SGPL1 variants in four patients, two of whom were first cousins. We describe in detail the proband, a boy born to Saudi Arabian consanguineous parents with a homozygous c.665G>A, p.R222Q SGPL1 variant. The patient presented with hypoglycemia and seizures at age 2 years and was ultimately diagnosed with PAI (isolated glucocorticoid deficiency). Brain MRI showed abnormalities in the basal ganglia consistent with a degenerative process albeit the patient had no neurologic symptoms. CONCLUSIONS: New genetic causes of PAI continue to be identified. We suggest that screening for SGPL1 mutations should not be reserved only for patients with nephrotic syndrome but may also include patients with PAI who lack other clinical manifestations of NPHS14 because, in certain cases, kidney disease and accompanying features might develop. Timely diagnosis of this specific sphingolipidosis while the kidneys still function normally can lead to prompt initiation of therapy and improve outcome.

Timing of Meal Insulin and Its Relation to Adherence to Therapy in Type 1 Diabetes.

The purpose of this study is to examine timing of meal insulin and further determine whether an association exists between timing of meal insulin and missed meal insulin doses. The cohort included 4768 T1D Exchange clinic registry participants <26 years with type 1 diabetes ≥1 year. Chi-square tests, t-tests, and regression were used to assess the relationship between participant characteristics and timing of meal insulin and missed meal doses, respectively. Timing of meal insulin and association with missed meal doses was analyzed using logistic regression. In all, 21% reported administering insulin several minutes before, 44% immediately before, 10% during, and 24% after meal. Participants who gave insulin prior to a meal had significantly lower HbA1c than those who gave insulin during or after meal (8.4% ± 1.5% vs 8.8% ± 1.6%, adjusted P < .001), but no significant association was observed regarding DKA events. Those who reported missing ≥1 insulin dose per week had higher HbA1c (9.8% ± 1.9% vs 8.3% ± 1.3%, adjusted P < .001) and were more likely to experience at least one DKA event (9% vs 5%, adjusted P = .001) compared with those who rarely missed a meal insulin dose. Participants who reported administering insulin during or after a meal were more likely to report missing ≥1 meal insulin dose per week compared with those who administered insulin before a meal (28% vs 14%, adjusted P < .001). Premeal insulin was associated with lower HbA1c and fewer missed meal insulin doses. Providers may use this information to discuss the benefits of premeal insulin on glycemic control and adherence to therapy.

Effect of oxandrolone therapy on adult height in Turner syndrome patients treated with growth hormone: a meta-analysis.

Turner syndrome is a chromosomal abnormality in which there is complete or partial absence of the X chromosome. Turner syndrome effects 1 in every 2000 live births. Short stature is a cardinal feature of Turner Syndrome and the standard treatment is recombinant human growth hormone. When growth hormone is started at an early age a normal adult height can be achieved. With delayed diagnosis young women with Turner Syndrome may not reach a normal height. Adjuvant therapy with oxandrolone is used but there is no consensus on the optimal timing of treatment, the duration of treatment and the long term adverse effects of treatment. The objective of this review and meta-analysis is to examine the effect of oxandrolone on adult height in growth hormone treated Turner syndrome patients. Eligible trials were identified by a literature search using the terms: Turner syndrome, oxandrolone. The search was limited to English language randomized-controlled trials after 1980. Twenty-six articles were reviewed and four were included in the meta-analysis. A random effects model was used to calculate an effect size and confidence interval. The pooled effect size of 2.0759 (95 % CI 0.0988 to 4.0529) indicates that oxandrolone has a positive effect on adult height in Turner syndrome when combined with growth hormone therapy. In conclusion, the addition of oxandrolone to growth hormone therapy for treatment of short stature in Turner syndrome improves adult height. Further studies are warranted to investigate if there is a subset of Turner syndrome patients that would benefit most from growth hormone plus oxandrolone therapy, and to determine the optimal timing and duration of such therapy.