Carotid endarterectomy versus stenting, 1999-2014

Lichtman et al in their article published in JAMA address the issue of carotid endarterectomy and stenting outcomes in the U.S. in the years 1999 to 2014.

In their study that included Medicare beneficiaries, the national annualized rate of carotid endarterectomy per 100 000 beneficiary-years decreased from 298 in 1999-2000 to 128 in 2013-2014, whereas the rate of carotid artery stenting initially 40 in 1999-2000 increased to 75 in 2005-2006 followed by a decline to 38 in 2013-2014.

During the study, 937 111 unique patients underwent carotid endarterectomy (mean age, 75.8 years) and 231 077 underwent carotid artery stenting (mean age, 75.4 years).

Outcomes improved over time despite increases in vascular risk factors such as hypertension prevalence that increased from 67% to 81% among patients who underwent endarterectomy and from 61% to 70% among patients who underwent stenting.  The adjusted annual decreases in 30-day ischemic stroke or death of 2.90% among patients who underwent endarterectomy and 1.13% among patients who underwent stenting.  The 1-year ischemic stroke decreased to 3.5% after endarterectomy and 1.6% after stenting. Additional improvements were noted for in-hospital mortality, 30-day stroke, myocardial infarction, or death, and 30-day all-cause mortality.

Carotid endarterectomies declined from 1999 to 2014, whereas carotid artery stenting increased until 2006 and then declined from 2007 to 2014. Outcomes improved despite increases in vascular risk factors.

Benefits and Risks of Mammography Screening

The article by Pace and Keating in JAMA reports on their MEDLINE search of articles and meta-analyses from 1960 to 2014 that describe benefits and/or harms of mammography, individualizing screening decisions and those promoting informed decision making.

They found that mammography screening is associated with a 19% overall reduction of breast cancer mortality (approximately 15% for women in their 40s and 32% for women in their 60s). For a 40- or 50-year-old woman undergoing 10 years of annual mammograms, the cumulative risk of a false-positive result is about 61%. About 19% of the cancers diagnosed during that 10-year period would not have become clinically apparent without screening (overdiagnosis), although there is uncertainty about this estimate.

They estimated that for every 10,000 women in their 40s who undergo annual mammograms for 10 years, 5 breast-cancer deaths will be averted. Of the remainder, about 25 would die despite being treated, and 36 would be treated unnecessarily because the cancer wouldn't have become life threatening.  For every 10,000 women in their 50s and those in their 60s screened annually for 10 years, 10 and 42 breast-cancer deaths would be averted respectively. But as many as 137 women in their 50s, and 194 in their 60s would be diagnosed and treated unnecessarily.  Women in all age groups will experience angst and inconvenience because of false positives diagnoses and unnecessary biopsies.

They conclude that although mammography screening may be associated with reduced breast cancer mortality it can also cause harm.  They suggest that in order to maximize the benefit of mammography screening, decisions should be individualized based on patients' risk profiles and preferences.

Pace LE, Keating NL; A systematic assessment of benefits and risks to guide breast cancer screening decisions: JAMA. 2014 Apr 2;311(13):1327-35.

doi: 10.1001/jama.2014.1398.