Research in brief

Abstract

Survivors of childhood cancer are at increased risk of developing endocrine disorders, according to data from a recent study. In the population-based study, data were analysed for 31 723 survivors of childhood cancer from Denmark, Finland, Iceland, Norway, and Sweden. Using registry data, follow-up begain 1 year after a childhood cancer diagnosis (median follow-up of 10 years, range 0–42). Survivors of childhood cancer had a 4·8-times increased risk for having at least one hospital contact for an endocrine disorder. Pituitary hypofunction, hypothyroidism, and testicular and ovarian dysfunction comprised 61% (655 of 1078) of all excess disease-induced and treatment-induced endocrine disorders. Survivors of childhood leukaemia and CNS cancer were at especially high risk of developing an endocrine disorder. Gastritis can lead to malabsorption of levothyroxine as a result of altering gastric juice pH. Whether taking levothyroxine with ascorbic acid (vitamin C) could improve thyroid hormone profile was tested in a small study. 31 patients with poorly controlled hypothyroidism and gastritis entered a 2 month control period, followed by a 2 month intervention phase, and a final 2 month control period. In the intervention phase, patients ingested their levothyroxine dose in 120ml of water containing vitamin C. Serum thyroid-stimulating hormone decreased in all patients during the intervention period, with an average decrease of 69·2%. Serum T4 was higher with the intervention in 30 of 31 patients. With malabsorption of levothyroxine posing a clinical barrier to adequate management of hypothyroidism, methods to overcome this are needed. Around 35% of adults in the USA are obese, according to results from the National Health and Nutrition Examination Survey. The authors used time-trend analysis to compare rates of obesity between 2003 and 2012. In the 2011–12 study period, almost 17% of 2–19-year-olds were obese, and the prevalence of high weight for recumbent length in infants and toddlers was 8%. Although no significant changes occurred between 2003–04 and 2011–12 in high weight for recumbent length among infants and toddlers or obesity in young people and adults, overall rates of obesity were high and surveillance is a key priority. Results of a proof-of-concept study suggest that SGLT2 inhibition holds some promise for management of type 1 diabetes as an adjunct to insulin. In a single-group, open-label trial, 40 adults with type 1 diabetes were given empagliflozin 25 mg daily for 8 weeks. Mean HbA1c decreased from 8·0% to 7·6% (p<0·0001), and was associated with a reduction in daily insulin dose (p<0·0001) and weight loss (p<0·0001). Two patients were withdrawn from the study because of diabetic ketoacidosis (one had severe gastroenteritis and the other insulin pump failure). This small study lends support to the design of large-scale studies investigating the effect of SGLT2 inhibition in type 1 diabetes. A new study has shed some light on the molecular basis of corticotropin-independent Cushing's syndrome. The investigators analysed samples from patients with adrenal cortex hyperplasia and a range of adrenal tumours. Exome sequencing showed that eight of 10 cortisol-producing adenomas had somatic mutations in PRKACA—a gene encoding the catalytic subunit of cAMP-dependent protein kinase. Comparative genomic hybridisation showed germline duplications of the PRKACA gene in five of 35 samples from patients with bilateral adrenal hyperplasias. All patients with PRKACA defects had overt Cushing's syndrome; patients with subclinical disease or other adrenal tumours showed no such defects. This study draws attention to the role of constitutive PKA activation in corticotropin-independent Cushing's syndrome. The opening or expansion of Native American-owned casinos can decrease the risk of overweight/obesity in childhood, note the authors of an ecological study. Anthropometric data were obtained from repeated cross-sectional fitness testing of Native American children between 2001 and 2012, from 117 Californian school districts. Of the 117 districts encompassing tribal lands, 57 gained or expanded a casino. For every slot machine gained per person, there was an associated increase of US$541 (95%CI $245–836) in annual income per person, and a decrease in BMI z-score (β=–0·003; 95% CI, −0·005 to −0·0002). In view of inherent limitations of this study, additional research is necessary to better appreciate the interplay between casino opening, economic resources, and childhood overweight/obesity.