DURHAM, NC — About 9.3 million fewer Americans would be recommended for primary-prevention statins if physicians followed 2016 recommendations based largely on LDL targets rather than competing 2013 guidelines based more on risk, a new study suggests.
After analyzing data from 3416 participants in the National Health and Nutrition Examination Survey (NHANES), researchers estimate that 15.8% of US adults aged 40 to 75 years without prior CVD would be started on statins if the 2016 US Preventive Services Task Force (USPSTF) recommendations were fully implemented vs 24.3% if the 2013 American College of Cardiology (ACC)/American Heart Association (AHA) guidelines were followed.
This is on top of the 21.5% of adults already taking lipid-lowering therapy and translates into an estimated 17.1 million vs 26.4 million Americans, respectively, with a new recommendation for statins.
"The number in and of itself is fairly substantial, but I think what's even more interesting and telling is who these individuals are," lead author Dr Neha Pagidipati (Duke Clinical Research Institute, Durham, NC) told heartwire from Medscape.
More than half (55%) of the roughly 9 million individuals who would be recommended for statins by ACC/AHA guidelines but not by USPSTF recommendations were aged 40 to 59 years and had a low 10-year CVD risk of 7% but a substantial mean 30-year risk of 34.6%.
"That's a one in three chance of developing a heart attack or stroke over the next 30 years, and that's a pretty sizable risk and a pretty sizable group," she said, noting that half of all CVD events in men and one-third in women occur before age 65.
In addition, more than a quarter of the individuals who would no longer be recommended for statins under the 2016 guidelines also had diabetes.
"There's a definite difference between the older and the newer guidelines in that individuals with diabetes aren't necessarily recommended to receive statin therapy. It depends on their other comorbidities and their overall risk," Pagidipati said.
She added, "It's hard to say whether or not it's a mistake, but I do think it's a concern, and it will be interesting to see whether or not practitioners will use these recommendations vs the older ones. The higher risk of individuals with diabetes is pretty ingrained in clinicians, so I think that is going to be a difficult thing to let go of."
The study was published today in the Journal of the American Medical Association.
Commenting to heartwire , Dr Michael Davidson (University of Chicago, IL), who was not involved in the study, said, "The diabetic population is the one that really is the most concerning to me, because that's a group we know die of heart disease in a greater percentage in their lifetime, so to wait until they're older will lead to confusion about how to treat."
He added, "That's a population where the US Preventive Services Task Force is going to be misleading to physicians."
Among those with diabetes not already on lipid-lowering therapy, the proportion of older patients (aged 60–75 years) recommended for statins would be similar under the USPSTF and ACC/AHA recommendations: 2.3% vs 2.5% of the primary-prevention population.
For younger patients (aged 40–59 years), however, the USPSTF would recommend statins for 42% of those recommended for statins under the ACC/AHA guidelines, representing 1.6% vs 3.8% of the primary-prevention population.
Davidson said part of the problem with both sets of recommendations is that risk is heavily driven by age.
"As a preventive cardiologist, the main issue for me is not 10-year risk but a lifetime risk and that early intervention is the most powerful way to prevent disease in a person's lifetime," he added.
Dr Steven E Nissen (Cleveland Clinic, OH) told heartwire the study "is to some extent proving the obvious."
He said it's self-evident that the ACC/AHA guidelines would end up treating more people because its threshold for treatment is 7.5% 10-year risk, whereas for the USPSTF it's 10%.
"Who's right? My own personal view is that we have a therapy, statins, that is very, very safe, is very effective in multiple populations, and is very inexpensive. So I tend to favor treating more people rather than fewer because at the end of the day you are going to prevent more events," he said.
Nissen stressed that the presence of multiple guidelines is very confusing to the public and to physicians. He noted that neither guideline is ideal and that he has been openly critical of the ACC/AHA guidelines because it uses a risk calculator that had never been previously published.
"It just wasn't a sensible thing to do, and I hope it's corrected in the next iteration of the guideline," which is currently under way, he added.
Pagidipati agrees that the current risk-based guidelines are not optimal and said they fail to adequately take into account the potential benefit of statin therapy in younger individuals.
"This highlights the fact that in the most current set of recommendations younger folks would potentially be left out," she said. "What that means in terms of longer-term outcomes, we only have cross-sectional data, but there is a lot of other literature to suggest these folks would benefit from therapy."
She added, "I think the next step is to improve the guidelines the next time around."
The study was supported by the Duke Clinical Research Institute. Pagidipati reports no relevant financial relationships. Disclosures for the coauthors are listed in the paper. Davidson reports consulting for Amgen and Regeneron Sanofi. Nissen reports no relevant financial relationships.
Heartwire from Medscape © 2017
Cite this: Do Latest US Guidelines Bypass, or Spare, Millions From Statins? - Medscape - Apr 19, 2017.