EBM Focus articles provide concise summaries of clinical trials most likely to inform clinical practice curated by the DynaMed® editorial team. Our team has selected the top influential summaries of the year.
CRP-guided Antibiotic Therapy for Acute Exacerbations of COPD: Fewer Prescriptions, Similar Outcomes
Reference: N Engl J Med 2019 Jul 11;381(2):11
Patients with chronic obstructive pulmonary disease (COPD) suffer from an average of one-two exacerbations per year. Guidelines recommend using three criteria to determine if antibiotic therapy is warranted: worsening dyspnea, increasing sputum volume, and increasing sputum purulence. Antibiotics are typically prescribed when two (including sputum purulence) or three of these criteria are met. As patients and providers may have a difficult time assessing sputum purulence and volume, more objective data points could potentially help limit unnecessary antibiotic prescriptions. An unblinded, multicenter clinical trial in the United Kingdom randomized over 600 patients presenting to their primary care provider (PCP) with symptoms of an acute COPD exacerbation to either point-of-care C-reactive protein (CRP)-guided antibiotic therapy or usual care.
Continuing to Debunk Ties Between MMR Vaccination and Autism Spectrum Disorder
Reference: Ann Intern Med 2019 Mar 5
Parents who choose not to vaccinate their children with the highly effective measles, mumps, and rubella (MMR) vaccine provoke a variety of responses from clinicians, ranging from gentle frustration to outright anger. The vaccine prevents upwards of 95 percent of clinical measles cases, yet rates of vaccination have declined precipitously since the fraudulent report published in The Lancet in 1998, which associated the vaccine with the onset of autism. Measles outbreaks continue throughout the world, resulting in over 100,000 deaths each year and millions of dollars spent to treat and prevent the spread of the disease. There are numerous reports demonstrating time and time again there is no association between MMR vaccination and autism. Now we have another study that clinicians can use as they engage parents in an effective conversation about vaccination.
Expert Opinion and Low-Quality Evidence Still Drive Many Strong Recommendations In Cardiology
Reference: JAMA. 2019 Mar 19;321(11):1069
Clinicians often consult clinical practice guidelines for recommendations regarding diagnostic and treatment options. Ideally, recommendations are based on the best available evidence, with the strength of the recommendation directly linked to the strength of the evidence. This should especially apply to cardiovascular disease guidelines, considering the relatively high volume of cardiology trials published in well-respected journals and over two billion dollars of NIH research funding allocated annually. Therefore, guidelines from the American Heart Association and American College of Cardiology (AHA/ACC) and European Society of Cardiology (ESC) published over the last decade were recently analyzed to determine the level of evidence supporting the many recommendations guiding current clinical practice.
Targeting the Brain: Lower Blood Pressure Targets May Not Reduce Dementia
Reference: JAMA 2019 Feb 12;321(6):553
The 2015 SPRINT trial demonstrated that intensive blood pressure control using a systolic blood pressure target of 120 mmHg reduced the risk of cardiovascular events and death from any cause compared to a target of 140 mmHg. This benefit is based on using a specific blood pressure measurement protocol and comes at a cost of increased risk of syncope and hypotension. The blood pressure measurement protocol required participants to sit alone in a quiet room for five minutes, after which time three separate automated blood pressure readings were obtained and averaged. The original trial was stopped early after four years due to a difference in the primary outcome. The SPRINT MIND trial is a prespecified examination of the effects of intensive blood pressure control on probable dementia.
Statin’ Young: Benefit of Starting Statins in Children with Familial Hypercholesterolemia
Reference: N Engl J Med. 2019 Oct 17;381(16):1547-1556
Familial hypercholesterolemia is a genetic disorder affecting 0.2 percent or more of many populations. It leads to impaired low-density lipoprotein (LDL) uptake and significant risk of premature cardiovascular disease. For more than a decade, the American Academy of Pediatrics has recommended universal screening between ages nine and 11 years of age (and earlier screening if there are additional risk factors), and the European Atherosclerosis Society and the American College of Cardiology/American Heart Association recommend beginning treatment with statins for affected children. Adherence to these recommendations has been limited because of the uncertain benefits and risks of starting asymptomatic children with a genetic disorder on powerful medications. This is why a recent study in the New England Journal of Medicine reporting significant benefit of statins in this population at 20-year follow-up is a really big deal. The baseline study two decades ago looked at the safety of two years of statin therapy on a cohort of children with genetically proven heterozygous FH, their unaffected siblings, and affected parents. The current follow-up study examined 214 of the affected children (now adults), their 156 affected parents, and 95 unaffected siblings.
