Cordova-Madera, Sandra

Abstract Context Levothyroxine is one of the most prescribed medications in the United States. Objective This study explores the appropriateness of levothyroxine prescriptions. Methods A retrospective multicenter study was conducted on adult patients who were prescribed levothyroxine for the first time between 2017 and 2020 at three academic centers in the United States. We classified each case of levothyroxine initiation into one of three mutually exclusive categories: appropriate (clinically supported), indeterminate (clinically unclear), or nonevidence based (NEB, not clinically supported). Results A total of 977 participants were included. The mean age was 55 years (SD 19), there was female (69%) and White race predominance (84%), and 44% had possible hypothyroid symptoms. Nearly half of the levothyroxine prescriptions were considered NEB (528, 54%), followed by appropriate (307, 31%) and indeterminate (118, 12%). The most common reason for NEB prescription was an index thyrotropin (TSH) value of less than 10 mIU/L without previous TSH or thyroxine values (131/528, 25%), for appropriate prescription, was overt hypothyroidism (163/307, 53%), and for an indeterminate prescription was a nonconfirmed subclinical hypothyroidism with TSH greater than or equal to 10 mIU/L (no confirmatory testing) (51/118, 43%). In multivariable analysis, being female (odds ratio [OR]: 1.3; 95% CI, 1.0-1.7) and prescription by a primary care provider (OR: 1.5; 95% CI, 1.2-2.0) were associated with NEB prescriptions. Conclusion There is a considerable proportion of NEB levothyroxine prescriptions. These results call for additional research to replicate these findings and to explore the perspective of those prescribing and receiving levothyroxine.

Abstract Background Obesity, defined by the World Health Organization (WHO) as a BMI greater than 30k g/m2, has reached epidemic proportions worldwide, related to approximately 2.8 million deaths/year as of June 2021. WHO sub-classifies obesity based on BMI in Class 1: 30–34.9 kg/m2, Class 2: 35–39.9 kg/m2, and Class 3: ≥40 kg/m2. This state of increased body weight is associated with an increased risk of cardiovascular disease. Cardiac remodeling can be affected by obesity and/or other cardiovascular risk factors (CVRF) as an adaptive physiological response. The remodeling patterns, Normal Geometry (NG), Concentric Remodeling (CR), Concentric Hypertrophy (CH), and Eccentric Hypertrophy, are classified by changes in Relative Wall Thickness (RWT), ≤ or >0.42, and/or Left Ventricular Mass Index (LVMI g/m2), ≤ or >88 for women and ≤ or >102 for men. Left Ventricular Ejection Fraction (LVEF) can remain within normal limits in patients with obesity with multiple CVRF and cardiac remodeling. Left Ventricular Global Longitudinal Strain (LV-GLS) and Right ventricular free wall strain (RV-FWS) can be useful to detect subclinical myocardial dysfunction. The aim of this study was to evaluate if these strain variables are affected in patients with obesity associated to other CVRF in relation to cardiac remodeling type when compared to controls. Methods 2859 patients with BMI ≥30 kg/m2 and 2616 normal-weight controls (BMI between 18.5 and 24.9 kg/m2), with normal and abnormal cardiac geometry, and normal ejection fraction by echocardiography performed between 01/01/2008 and 12/31/2018, were compared. Obesity was classified based on the World Health Organization. CVRF included were Hypertension (HTN), Diabetes Mellitus (DM), Dyslipidemia, history of Vascular Event (myocardial infarction and/or stroke), and Obstructive sleep apnea (OSA). Results BMI, cardiac geometry, CVRF, and the number of comorbidities independently affected GLS and RV-FWS (Figure 1 and Figure 2). LV-GLS and RV-FWS values [mean (SD)] in obesity classes 1, 2, and 3 were −19 (2.9), −18.9 (2.9), −18.7 (2.9) & −24.2 (5.2), −23.8 (6.2), −24.5 (5.9), respectively. In the control group LV-GLS and RV-FWS values [mean (SD)] were −20.1 (3.0) & −27 (5.6), respectively. CH was associated with the greatest decrease in LV-GLS and RV-FWS in males and females, regardless of BMI (Figure 2). LV-GLS values [mean (SD)] associated to CH for obesity class 1, 2, and 3, and controls in females were −18.4 (3.4), −18 (3.1) −17.6 (3.6), and −17.8 (4), respectively, and for obesity class 1, 2, and 3, and controls in males were −16.1 (3.5), 16.5 (3.2), −14.4 (2.7), and −16.6 (4.7), respectively (Figure 1). Conclusion Obesity associated to CVRF and CH have the lowest values of GLS in patients with normal ejection fraction. These values were exceedingly below average compared to other groups. These parameters should be used as reference values for this population. Funding Acknowledgement Type of funding sources: None.