Primecuts – This Week in the Journals

January 14, 2019


By Emily North, MD

Peer Reviewed

With medicine advancing at such a rapid pace, it is crucial for physicians to keep up with the medical literature.  This can quickly become an overwhelming endeavor given the sheer quantity and breadth of literature released on a daily basis. Primecuts helps you stay current by taking a shallow dive into recently released articles that should be on your radar. Our goal is for you to slow down and take a few small sips from the medical literature firehose. 

Assessment of a Targeted Electronic Health Record Intervention to Reduce Telemetry Duration: A Cluster-Randomized Clinical Trial [1]

Telemetry is often ordered for patients with the thought that more monitoring will lead to better care, but there are clear downsides to increased monitoring. Alarm fatigue from ‘false’ alarms – estimated to comprise 80-99% of alarms in the hospital – as well as inefficient use of resources are two major motivating factors to improve how we use telemetry [2].

In this study, house-staff teams at a single academic medical center were randomized to an EHR-triggered pop-up notification of when to discontinue telemetry (depending on patient indication) in general medicine patients over a six-month period. This notification was activated when the patient’s telemetry order met the duration of telemetry recommended based on indication (based on a combination of 2004 AHA practice standards and local expert opinion) during daytime hours, at a time when a member of the primary medical team was entering orders into the EHR. When notified, 62% of house-staff teams chose to discontinue monitoring, leading to a decrease of nearly nine hours of monitoring on average without a significant change in rapid responses or medical emergencies.

This study is an interesting application of how we may use a relatively new form of technology, the EHR, to place appropriate limits on how we use other forms of technology such as telemetry. Besides reducing alarm fatigue in physicians by increasing the yield of the data collected on patients, this study indicates how we might use resources such as the increased monitoring in the telemetry unit more efficiently.

The impact of repeated vaccination on influenza vaccine effectiveness: a systematic review and meta-analysis [3]

Studies in the 1970s and 1980s as well as more recent years have had varied findings as to whether or not past history of influenza vaccination has an effect on the effectiveness of the current season’s vaccine [4]. As the influenza vaccine is recommended annually, older adults are increasingly likely to have had a significant history of previous seasonal influenza vaccinations. However, they are also more susceptible to influenza-related complications if they do contract the flu [5]. This has led to interest in whether or not continuing to recommend the flu vaccine annually leads to increased susceptibility of contracting the flu over the course of multiple yearly vaccinations.

This study is a meta-analysis of 20 observational studies of vaccine effectiveness in patients of all four combinations of having been vaccinated or not in the prior and current seasons. The authors found that regardless if a vaccination was received in the prior season, being vaccinated in the current season is associated with a lower risk of contracting the flu. However, they also found that the influenza vaccine is less effective against H3N2 and B, but not for H1N1 if the patient is vaccinated in both the immediate prior and current season.

In practice, as we cannot predict what strains the patient might be exposed to, and vaccination in the current season is associated with greater protection against influenza in the current season regardless of prior vaccination status, the results of this study continue to support current advice to receive the influenza vaccine annually. However, a significant limitation of this study is that it only reviewed vaccination history including the current and past seasons. Studies of more comprehensive influenza vaccination history are needed to further examine any potential impact of several years of annual influenza vaccinations.

Outcomes Associated with De-escalating Therapy for Methicillin-Resistant Staphylococcus aureus in Culture-Negative Nosocomial Pneumonia [6]

As MRSA is less frequently identified as the cause of nosocomial pneumonia, and there is increasing global concern for increasing rates of antibiotic-resistant infections, it is prudent to know when narrowing broad-spectrum coverage of antibiotics is appropriate [7]. As the authors of this study note, it is common practice to narrow when a culture has speciated and sensitivities are identified, but it can be more challenging to determine how to narrow when cultures are often negative.

This single-center retrospective cohort study of 279 adult patients with a diagnosis of nosocomial pneumonia and negative respiratory cultures investigated outcomes when patients were discontinued from anti-MRSA agents within the first four days of initiation of antibiotics. Most patients were white men, and 87% were admitted to the ICU during the course of their illnesses. Nosocomial pneumonia was diagnosed at a median of hospital day 7. Patients with earlier discontinuation of anti-MRSA agents (of which 78% were given vancomycin) were found to have no change in 28-day mortality, shorter length of hospital and ICU stays, and lower incidence of AKI.

As anti-MRSA agents such as vancomycin and linezolid are associated with such adverse effects as acute kidney injury and serotonin syndrome respectively, there are potentially more acute harms of using these antibiotics – as with any medication – with our patients, besides the risk of developing antibiotic resistance. Although this study is limited by its retrospective design and the decision of when to narrow antibiotics likely was influenced by unmeasured factors, events such as ICU admission and use of vasopressors did not differ significantly between the two groups. This indicates that the baseline level of illness was similar, and it is less likely patients were narrowed because they were less sick. Instead of relying solely on positive culture data to guide our choice of antibiotics, this study provides evidence for the strategy of using the absence of culture data to influence this decision, leading to reducing the risk of developing antibiotic resistance and potential toxicities of anti-MRSA agents.   

Marine n-3 Fatty Acids and Prevention of Cardiovascular Disease and Cancer [8]

It seems likely that every physician has been asked about the utility of nutritional supplements from vitamin C to spirulina. However, so far there has been limited data on which (if any) supplements bought over-the-counter have any benefit to the average consumer, leaving the primary care physician at a loss as to how to properly counsel patients.

This was a randomized, double-blind, placebo-controlled trial to investigate the value of n-3 fatty acids and vitamin D3 as primary prevention of cardiovascular disease and cancer in 25,871 men age 50 and older and women age 55 and older. Of note, the study population was diverse and included over 20% black patients (of those with available race/ethnicity data).  Patients were randomized to combinations of 840mg n-3 fatty acids (the dose positively associated with secondary prevention in a prior study) or placebo, and either 2000IU D3 or placebo per day.  At a median follow-up of 5.3 years, this trial did not find a significant difference in major cardiovascular events or invasive cancer between the n-3 fatty acid and placebo groups.

As marine n-3 fatty acid — or more commonly known as ‘fish oil’ — supplements are very popular with patients, this large study of a diverse patient group will aid in more effectively guiding patients with respect to scientific evidence on this particular supplement. However, there are some limitations of this trial. These include that the benefits of fish oil supplementation may require a much longer follow-up time in order to see an effect, and that the benefits of supplementation may only seen when taken much earlier or longer in a patient’s lifetime. More research into these and other supplements will be necessary to further characterize any benefit to products patients may purchase over the counter. 

Mini-Cuts: This week’s mini-cuts:

  • Screening the Blood Supply for Zika Virus in the 50 U.S. States and Puerto Rico: [9] Due to the significant increase in rates of Zika in 2015, the FDA halted blood collection in Puerto Rico in early 2016 until universal blood testing for the virus was in place. This study investigated the utility of continuing to screen for Zika virus in the blood supply of the entire 50 United States, and found that it was not cost-effective aside from during peak mosquito season in the territory of Puerto Rico, when the estimated rate of Zika virus-positive blood donations was 0.66%.
  • Fracture Risk After Initiation of Use of Canagliflozin: A Cohort Study: [10] As canagliflozin is associated with decreased bone mineral density, and diabetic patients are known to have an increased risk of developing fractures, there has been concern for a potential increased risk of fracture in patients on this medication. This observational study of nearly eighty thousand middle-aged patients starting use of canagliflozin vs a GLP-1 agonist, found no difference in fracture at a mean follow-up duration of 34 weeks.
  • Withdrawal of pharmacological treatment for heart failure in patients with recovered dilated cardiomyopathy (TRED-HF): an open-label, pilot, randomised trial: [11] The risk of discontinuing treatment is in patients with dilated cardiomyopathy who are asymptomatic and regained normal cardiac function and are asymptomatic has yet remained unknown. This open-label, pilot, study sought to investigate outcomes when randomizing patients to stop versus continue therapy, with the finding that 40% had a relapse of dilated cardiomyopathy at 6 months.

Dr. Emily North is a resident physician, internal medicine at NYU Langone Health

Peer reviewed by Kevin Hauck, MD, attending physician, Hospitalist, NYU Langone Health

Image courtesy of Wikimedia Commons

References: 

[1] Najafi N, Cucina R, Pierre B, Khanna R. Assessment of a Targeted Electronic Health Record Intervention to Reduce Telemetry Duration: A Cluster-Randomized Clinical Trial. JAMA Intern Med. 2019;179(1):11–15. doi:10.1001/jamainternmed.2018.5859 https://jamanetwork.com/journals/jamainternalmedicine/fullarticle/2717954

[2] Srinivasa E, Mankoo J, Kerr C. An Evidence-Based Approach to Reducing Cardiac Telemetry Alarm Fatigue. Worldviews Evid Based Nurs. 2017;14(4):265-273. doi: 10.1111/wvn.12200. https://sigmapubs.onlinelibrary.wiley.com/doi/full/10.1111/wvn.12200

[3] Ramsay LC, Buchan SA, Stirling RG, et al. The impact of repeated vaccination on influenza vaccine effectiveness: a systematic review and meta-analysis. BMC Med. 2019;17:9. https://doi.org/10.1186/s12916-018-1239-8https://bmcmedicine.biomedcentral.com/articles/10.1186/s12916-018-1239-8

[4] Belongia EA, Skowronski DM, McLean HQ, Chambers C, Sundaram ME, De Serres G. Repeated annual influenza vaccination and vaccine effectiveness: review of evidence. Expert Rev Vaccines. 2017 Jul;16(7):1-14. doi: 10.1080/14760584.2017.1334554.

[5] Schaffner W, Chen WH, Hopkins RH, Neuzil K. Effective Immunization of Older Adults Against Seasonal Influenza. Am J Med. 2018 Aug;131(8):865-873. doi: 10.1016/j.amjmed.2018.02.019. https://www.amjmed.com/article/S0002-9343(18)30206-7/fulltext

[6] Cowley MC, Ritchie DJ, Hampton N, Kollef MH, Micek ST. Outcomes Associated With De-escalating Therapy for Methicillin-Resistant Staphylococcus aureus in Culture-Negative Nosocomial Pneumonia. Chest. 2019 Jan;155(1):53-59. https://doi.org/10.1016/j.chest.2018.10.014

[7] Ventola CL. The Antibiotic Resistance Crisis: Part 1: Causes and Threats. P T. 2015 Apr; 40(4): 277-283. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4378521/

[8] Manson JE, Cook NR, Lee I, et al. Marine n-3 Fatty Acids and Prevention of Cardiovascular Disease and Cancer. N Engl J Med. 2019; 380:23-32. DOI: 10.1056/NEJMoa1811403. https://www.nejm.org/doi/full/10.1056/NEJMoa1811403

[9] Russell WA, Stramer SL, Busch MP, Custer B. Screening the Blood Supply for Zika Virus in the 50 U.S. States and Puerto Rico: A Cost-Effectiveness Analysis. Ann Intern Med. 2019 Jan 8. doi: 10.7326/M18-2238. http://annals.org/aim/fullarticle/2720163/screening-blood-supply-zika-virus-50-u-s-states-puerto#

[10] Fralick M, Kim SC, Schneeweiss S, Kim D, Redelmeier DA, Patorno E. Fracture Risk After Initiation of Use of Canagliflozin: A Cohort Study. Ann Intern Med. 2019 Jan 1. doi: 10.7326/M18-0567. http://annals.org/aim/fullarticle/2719985/fracture-risk-after-initiation-use-canagliflozin-cohort-study

[11] Halliday BP, Wassall R, Lota AS, et al. Withdrawal of pharmacological treatment for heart failure in patients with recovered dilated cardiomyopath (TRED-HF): an open-label, pilot, randomised trial. Lancet. 2019 Jan; 393(10166):p61-73. doi: https://doi.org/10.1016/S0140-6736(18)32484-X.https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(18)32484-X/fulltext