Real-world use of glucagon-like peptide-1 receptor agonists in youth with type 2 diabetes is associated with short-term improvements in HbA1c.

AIM: To assess the short-term, real-world use and effectiveness of glucagon-like peptide-1 receptor agonist (GLP-1RA) medications in the management of type 2 diabetes (T2D) in a diverse cohort of youth. METHODS: This multicentre retrospective study analysed youth prescribed a GLP-1RA for the management of T2D at two academic paediatric diabetes centres prior to June 2022. Change in HbA1c and insulin use from baseline to first (median 91 days) and second (median 190 days) follow-up were evaluated for those taking a GLP-1RA. Multivariable linear mixed effects models adjusting for baseline sex, age, race/ethnicity, insurance, insulin regimen, metformin regimen, GLP-1RA dosing frequency and the body mass index Z-score (BMI-Z) examined the change in HbA1c for participants for up to 6 months after baseline. RESULTS: A total of 136 patients with T2D (median age 16.1 [interquartile range 13.9-18.0] years, 54% female, 56% non-Hispanic Black, 24% Hispanic, 77% with public insurance) were prescribed GLP-1RAs and taking them at first or second follow-up. Median HbA1c decreased from 7.9% to 7.6% (P < .001) at a median follow-up of 91 days (n = 109) and, among those with HbA1c available at baseline and second follow-up (n = 83), from 8.4% to 7.4%. The proportion of patients prescribed insulin decreased from baseline to the first follow-up visit (basal 69% to 60% [P = .008], prandial 46% to 38% [P = .03]). In multivariable analysis, there was a mean decrease in HbA1c by 0.09 percentage points per month (P = .005, 95% confidence interval -0.15, -0.03). CONCLUSIONS: Real-world use of GLP-1RAs in youth with T2D is associated with decreased HbA1c levels, despite challenges with access and adherence. GLP-1RA treatment may reduce insulin doses for youth with T2D.

A De Novo Deleterious PHEX Variant Without Clinical Features of X-Linked Hypophosphatemia.

X-linked hypophosphatemia (XLH), the most common form of hereditary rickets, is due to inactivation of PHEX, resulting in increased circulating fibroblast growth factor 23. Consequent renal phosphate loss leads to hypophosphatemia, rickets, and progressive bow deformity. Inheritance is X-linked dominant, such that heterozygous females are affected, as well as hemizygous males. A 10-month-old girl was referred for potential treatment for presumed XLH. Amniocentesis, performed following prenatal identification of duodenal atresia, polyhydramnios, and intrauterine growth restriction, revealed a de novo X-chromosomal deletion encompassing 10 genes, including PHEX. Postnatal genetic testing confirmed presence of the deletion in the baby. She demonstrated no phenotypic, biochemical, or radiographic features of XLH. Neither parent had features of XLH, nor carried the deletion. Given the discordance between genotype and phenotype, evaluation for skewed X-inactivation was pursued. Methylation analysis via the androgen receptor locus was inconclusive, thus RNA sequencing was pursued. Analysis of 12 high-quality single nucleotide polymorphisms (SNPs) that are expressed in mRNA revealed skewed X-inactivation. Heterozygous disruption of PHEX typically confers a diagnosis of XLH. Skewed X-inactivation, whereby one X chromosome is preferentially silenced, appears to have protected this patient from the expected expression of an X-linked dominant disorder.