First trimester exposure to antithyroid drugs associated with birth defects

1. First trimester exposure to antithyroid drugs associated with birth defects
Abstract: http://annals.org/aim/article/doi/10.7326/M17-1398
URLs go live when the embargo lifts

Taking antithyroid drugs (ATDs) during the first trimester of pregnancy is associated with an increased risk for birth defects, particularly for women receiving prescriptions for methimazole (MMI) or both MMI and propylthiouracil (PTU). The findings are published in Annals of Internal Medicine.

Researchers from Sungkyunkwan University School of Medicine, Gangnam-gu, Seoul, Korea, conducted a nationwide cohort study to examine the association between maternal prescriptions for ATDs and congenital malformations in live births. The study included a cohort of 2,886,970 pregnancies linked to live-born infants in 2,210,253 women between 2008 and 2010. Of those, 12,891 pregnancies were exposed to ATDs during the first trimester. The data showed that prenatal exposure to MMI and PTU during the first trimester resulted in relative increases in the risk for congenital malformations of 31% and 16%, respectively. The increased risk for malformations associated with MMI remained among those who switched to PTU several months before their pregnancy or during the first trimester.

The researchers conclude that ATD exposure during the first trimester of pregnancy is associated with significantly increased risk for congenital malformations. These findings confirm the importance of minimizing MMI use in the first trimester and suggest that the current recommendation of switching from MMI to PTU after pregnancy detection should be reconsidered.

Media contacts: For an embargoed PDF, please contact Angela Collom. For an interview with the lead author, Jae Hoon Chung, MD, PhD, please email thyroid@skku.edu or aledma623@gmail.com.

2. Insufficient evidence to determine if marijuana use can affect cardiovascular risk
Several studies suggested a metabolic benefit from marijuana use, but they were not supported by prospective studies
Abstract: http://annals.org/aim/article/doi/10.7326/M17-1548
URLs go live when the embargo lifts

A systematic review of published studies found insufficient evidence to determine if marijuana use has any effect, good or bad, on cardiovascular risk factors or outcomes. The findings are published in Annals of Internal Medicine.

Researchers from The Wright Center for Graduate Medical Education, Scranton, Pennsylvania, the University of California, San Francisco and the San Francisco VA reviewed 24 observational studies of adults using any form of marijuana and vascular risk factors (hyperglycemia, diabetes, dyslipidemia, obesity) or outcomes (stroke, myocardial infarction, cardiovascular mortality, and all-cause mortality) in cardiovascular cohorts. The researchers found insufficient evidence to draw any conclusions about the effect of marijuana use on those outcomes. The studies that suggested a metabolic benefit from marijuana use were based on cross-sectional designs and were not supported by more rigorously designed prospective studies.

The authors conclude that adequately powered prospective studies are needed to determine the effect of chronic marijuana use on cardiovascular health.

Media contacts: For an embargoed PDF, please contact Angela Collom. For an interview with Divya Ravi, MD, MPH, please email her directly at divyaravi.88@gmail.com.

3. Latest ACC/AHA hypertension guidelines recommend too many patients for drug treatment
Under new guidelines, prevalence of hypertension increases 14 percent in the U.S.
Abstract: http://annals.org/aim/article/doi/10.7326/M17-3203
Editorial: http://annals.org/aim/article/doi/10.7326/M17-3293
URLs go live when the embargo lifts

The latest hypertension guidelines from the American College of Cardiology and the American heart Association (ACC/AHA) revise blood pressure classifications, thereby increasing the prevalence of hypertension by about 14 percent in the United States. Under the new guidelines, a reading of 120-129/<80 mm Hg is considered prehypertensive and a reading of 130-139/80-89 mm Hg is hypertensive. A synopsis of the guidelines is published in Annals of Internal Medicine.

The new guidelines differ significantly from several published guidelines, including those developed by the American College of Physicians (ACP) and the American Academy of Family Physicians (AAFP). According to Amir Qaseem, MD, PhD, Vice President of ACP's Clinical Policy and Center for Evidence Reviews, the ACC/AHA recommendations place too many patients in the hypertensive category, subjecting them to treatment. This approach falls short in weighing the potential benefits against potential harms, costs, and individual patient preferences.

ACP believes that pharmacologic initiation and treatment targets of less than 130/80 mm Hg in a broad population of older adults is not strongly supported by evidence and may result in low value care for several reasons. First, clinical trials do not provide consistent evidence of benefit of SBP targets less than 130 mm/Hg in older adults, including those with diabetes or kidney disease. Second, trials often overestimate the benefits and underestimate harms seen when findings are applied to broad primary care populations. And third, there is no RCT evidence to support a DBP target of less than 80 mm Hg.

Media contacts: For an embargoed PDF, please contact Angela Collom. For an interview with guideline author, Robert Carey, MD, please contact Eric Swenson at EWS3J@hscmail.mcc.virginia.edu. For an interview with editorialist, Amir Qaseem, MD, PhD, please contact Steve Majewski at smajewski@acponline.org or 215-351-2415.

Also new in this issue:
Expansion of the Classification System for Eagle Syndrome
Radoslaw Kazmierski, MD, PhD; Malgorzata Wiezbika, MD, PhD; Ewa Kotecka-Sowinska, MD; Jacek Banaszewski, MD, PhD; Mikolaj A. awlak, MD, PhD
Brief Case Report
Abstract: http://annals.org/aim/article/doi/10.7326/L17-0507

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