Background. The short cosyntropin test is widely used for adrenal insufficiency screening and diagnosis. Lower cosyntropin doses may have greater sensitivity vs. the standard dose in detecting adrenal dysfunction. Obesity and overweight are increasing, impacting the clinical presentation of some diseases. Currently more than 50% of the subjects diagnosed with autoimmune adrenal insufficiency have a BMI greater than 25, and hence individuals living with overweight and obesity are more frequently requiring evaluation of the adrenal cortical function. Fixed-dose cosyntropin stimulation may not be appropriate for individuals with obesity. Objective. The primary objective was to compare cortisol response to a weight-adapted cosyntropin dose vs. a fixed low dose (1 µg) and a more physiologically fixed dose (10 µg). Methods. Twenty individuals with obesity and 20 age-matched healthy controls underwent in a randomized sequence at least one-week apart, to the The short cosyntropin test with three different doses, 0.2 µg/kg of body weight, 1 or 10 µg fixed dose stimuli. The assessment and data analysis were blinded to the individual and the investigator. Results. Cortisol response was reduced in the group with obesity with the 1 µg fixed dose stimuli at 30 minutes (median, IQR) 649.6 µg, 567.3–738.4 µg for the control group vs. 568.6 µg, 528.4–623.13 µg, p = 0.04 ; there was a lower cortisol peak at 60′ in all the three evaluated doses, with a dose-dependent trend. A weight-adapted cosyntropin dose of 0.2 µg in obesity produces a similar response to the one observed in individuals without obesity. The 1 µg ACTH test falls short on stimulating the cortisol adrenal response in individuals with obesity.
Carotid Intima-Media Thickness in Patients with Subclinical Hypothyroidism: A Prospective Controlled Study
Purpose The association between subclinical hypothyroidism (SCH) and cardiovascular risk, particularly with a TSH <10 µIU/ml, remains controversial. The objective of our study was to assess the association between SCH and cardiovascular risk through carotid intima-media thickness, and alternatively, to evaluate its change after treatment with levothyroxine. Methods A total of 54 individuals were included in the study: 18 with SCH; 18 with overt hypothyroidism (OH); and 18 healthy controls (HC). The carotid intima-media thickness was measured in each group. In SCH, follow-up was performed at three and six months after the start of levothyroxine treatment. Results The mean age of the total population at baseline was 35.8 years. The median TSH in SCH was 6.15 µIU/ml. The carotid intima-media thickness (mean and standard deviation) was greater in SCH in comparison to the HC group: right common carotid artery (RCCA), 0.486 ± 0.106 mm and 0.413 ± 0.075 mm in SCH and HC, respectively, p=0.01 and left common carotid artery (LCCA), 0.511 ± 0.144 mm and 0.427 mm ± 0.090 in SCH and HC, respectively, p=0.03). In patients with SCH, there was a decrease in the carotid intima-media thickness after treatment with levothyroxine (RCCA and LCCA, p <0.05 at three and six months). Conclusions There was an association between increased carotid intima-media thickness in patients with SCH in comparison with HC, even with a TSH <10 µIU/ml. The increase was reversed with levothyroxine therapy. The association of this increased thickness with important cardiovascular outcomes remains uncertain and should be evaluated in future studies.
Early triglyceride and glucose index as a risk marker for gestational diabetes mellitus
AbstractObjectiveTo assess the risk of gestational diabetes mellitus (GDM) according to the triglyceride and glucose (TyG) index values during the first trimester of pregnancy in Latin American women.MethodsPregnant women were enrolled at their first prenatal visit at the Obstetric Division in the University Hospital “Dr. José E. González”. Triglycerides and fasting plasma glucose (FPG) were collected to determine the TyG index. GDM diagnosis was performed by a single‐step 2‐hour 75‐g oral glucose tolerance test. Generalized linear models were used to determine risk ratios; pregnancy outcomes at delivery were collected from the hospital medical records.ResultsA total of 164 pregnant women were included. GDM was present in 29 (17.7%) women. No significant differences in age, first‐trimester body mass index (BMI, calculated as weight in kilograms divided by the square of height in meters), family history of diabetes, and TyG index were observed between GDM cases and the reference group without GDM. The adjusted analysis showed no association between TyG and GDM (risk ratio [RR] 1.03, 95% confidence interval [CI] 0.57–1.88]). Higher TyG index values between women with and without a diagnosis of GDM in the second trimester were observed. No significant differences were identified in pregnancy outcomes, although a trend was observed for hyperbilirubinemia in women with first‐trimester TyG index values greater than 8.7.ConclusionsOur findings do not support the use of the TyG index for GDM prediction in Latin American women.
Diagnostic accuracy of the triglyceride-glucose index for gestational diabetes screening: a practical approach
Introduction . The triglyceride and glucose (TyG) index has been described as a biochemical marker of insulin resistance (IR); however, its diagnostic accuracy remains uncertain. Objective . To summarize the evidence assessing the diagnostic accuracy of the TyG index regarding IR. Methods . A comprehensive search in MEDLINE, EMBASE, Web of Science, and Scopus was performed without any language restriction. Studies assessing the diagnostic accuracy of the TyG index against the hyperinsulinemic-euglycemic clamp (HIEC) or any other IR biochemical were assessed independently and in duplicate. Diagnostic accuracy measures (sensitivity, specificity, positive predictive value, negative predictive value, and likelihood ratios) were extracted independently and in duplicate. The QUADAS-2 tool was used to assess the risk of bias of independent studies. Results . We identified 15 eligible studies with 69,922 participants and an overall quality of low to moderate. The TyG index was evaluated by HIEC and HOMA as reference tests. The highest achieved sensitivity was 96% using HIEC, and the highest specificity was of 99% using HOMA-IR, with a cutoff value of 4.68. AUC values varied from 0.59 to 0.88. Cutoff values for IR were variable between studies, limiting its comparability. Conclusion . In this systematic review, we found moderate-to-low quality evidence about the usefulness of the TyG index as a surrogate biochemical marker of IR. Due to the lack of a standardized IR definition and heterogeneity between studies, further validation and standardized cutoff values are needed to be used in clinical practice.
Acanthosis nigricans in middle‐age adults: A highly prevalent and specific clinical sign of insulin resistance
Background . Hypertriglyceridemia and hyperglycemia coexist in 30-60% of patients with diabetes. The impact of hypertriglyceridemia regarding HbA1c assay reliability remains uncertain. Therefore, we conducted a prospective in vivo controlled study with the aim of defining the association between triglyceride levels and HbA1c. Methods . A total of 44 patients with an index-hospital admission diagnosis of diabetic ketoacidosis or hypertriglyceridemia-induced pancreatitis, as a model for acute elevation of triglycerides, were recruited. Blood samples were drawn for the measurement of HbA1c, triglycerides, glucose, and hemoglobin at baseline and subsequently 24 and 48 hours after admission. HbA1c analysis was performed with high-performance liquid chromatography Bio-Rad D10 (NGSP approved). Results . All patients completed the study protocol. A difference between mean triglycerides from day 0 (baseline) to day 2 of 1567.2 mg/dL was observed. We found a difference between mean serum HbA1c from days 0 to 2 of 0.09% [1 mmol/mol] ( p = 0.004 ). Moreover, a weak correlation between the mean difference of HbA1c and triglycerides from baseline to day 2 was found to be statistically significant ( r = 0.256 , p = 0.015 ). None of these findings, however, are clinically significant. Conclusion . Triglycerides do not impair the interpretation of HbA1c assay. Patients and clinicians can now be confident that hypertriglyceridemia is not an important factor when interpreting HbA1c results.