PrimeCuts: This Week in the Journals

November 23, 2009

Turkey

Rennie Rhee MD

Less is more, some say, and this past week the general direction of screening guidelines seems to affirm this mantra.  After an unprecedented change in the United States Preventive Services Task Force’s (USPSTF) guidelines for breast cancer screening, the American College of Obstetricians and Gynecologists1 (ACOG) announced on Friday, November 20th their new recommendation to delay the onset of cervical cancer screening and to screen less frequently. Of course, following years of aggressive campaigning for preventive medicine and innumerable cancer awareness programs, the natural response of the community is alarm and apprehension.  But, based on recent studies, the continual oath to do no harm has prevailed, although how this will affect practice is yet to be seen.

ACOG recommends beginning baseline cervical screening at age 21 regardless of age of first sexual intercourse.  In addition, women ages 21 to 30 should be screened every two years instead of annually with standard Pap or liquid-based cytology.  After 30 years of age, women with three consecutive negative test results may be screened every three years.  Certain populations at high risk, such as immunosuppressed patients or those already treated for cervical intraepithelial neoplasia (CIN) 2 or 3 or cervical cancer should be screened more frequently.

The more conservative approach attempts to avoid unnecessary treatment of adolescents and young adults who are already at low risk for cervical cancer.  Precancerous lesions are more common in adolescents but tend to resolve without treatment. However, standard protocol for treating these lesions often results in excisional procedures that are thought to have led to a significant increase in premature births and need for Caesarean sections.

Less is indeed more, says a study in The Lancet2 this week that compared routine to on-demand chest radiographs in mechanically ventilated patients in the intensive care unit (ICU).  Twenty-one ICUs in France were randomized to order chest radiographs routinely versus based on clinical examination during morning rounds.  In this cluster-randomized design, the ICU then switched protocol during a second period so that all units received both methods of treatment.  Results showed that the on-demand strategy utilized substantially fewer radiographs without affecting therapeutic or diagnostic interventions, length of stay in the ICU, duration of mechanical ventilation, or mortality.  Although implementation of the on-demand strategy still requires further study and depends on physician level of comfort, our use of diagnostic tools is yet again under scrutiny.

Does the treatment of anemia in patients with type 2 diabetes mellitus and chronic kidney disease reduce mortality, cardiovascular events, and progression to end stage renal disease?  Not so, according to the Trial to Reduce Cardiovascular Events with Aranesp Therapy (TREAT) published this week in the New England Journal of Medicine.3 In this randomized controlled trial, 2012 patients with type 2 diabetes mellitus, chronic kidney disease, and anemia were assigned to darbepoetin alfa to achieve a hemoglobin of 13 g/dL or to placebo, only receiving rescue darbepoetin alfa when hemoglobin dropped below 9 g/dL.  After a median follow-up of 29 months, no difference was seen between the two groups in terms of death or cardiovascular events, but an increased risk of stroke was seen in the darbepoetin group.

On the flip side, more is sometimes better, particularly in the world of cardiology.  The Pacing to Avoid Cardiac Enlargement (PACE) study4 published online in The New England Journal of Medicine compared biventricular pacing to right ventricular apical pacing by randomizing 177 patients with a biventricular device and normal systolic function to receive either biventricular pacing or right ventricular apical pacing.  After 12 months, the primary end point of left ventricular ejection fraction was significantly lower in the right ventricular group (54.8±9.1% vs. 62.2±7.0%, P<0.001).  The left ventricular end-systolic volume was also significantly higher in the right ventricular group (35.7±16.3 ml vs. 27.6±10.4 ml, P<0.001), regardless of the presence of diastolic dysfunction at baseline.  The study is limited by a small sample size as well as the lower success rate of implanting a biventricular pacing system compared to the conventional dual-chamber pacing.

When it comes to prevention, treatment of obstructive sleep apnea (OSA) plays a substantial role in reducing the risk of cardiovascular events, not to mention improving quality of life.  But anyone within five miles of a continuous positive airway pressure machine knows that compliance is an ongoing battle.  The CPAP Promotion and Prognosis – The Army Sleep Apnea Program (CPAP ASAP) was a randomized controlled trial published in the Annals of Internal Medicine5 that studied the use of eszopiclone (Lunesta), a non-benzodiazepine sedative-hypnotic, at the onset of therapy in improving CPAP usage. One hundred sixty patients with newly diagnosed OSA initiating CPAP were randomized to receive eszopiclone or placebo for the first 14 nights.  After a 24-week follow-up, patients in the eszopiclone group used CPAP 64.4% of nights compared with 45.2% in the placebo group (difference 20.8%, p=0.003).  Patients in the eszopiclone group used CPAP 1.3 more hours per night for all nights and 1.1 more hours per night of CPAP use.  No difference in side effects between the groups was observed.  A limitation of the study was the possibility of undertreated insomnia in the placebo group, which may have led to biased results.  Overall, the use of better-fitted masks, humidified air, and close follow-up along with a long-acting non-benzodiazepine sedative-hypnotic like eszopiclone may improve compliance with CPAP use.

As we sum up this week’s Primecuts, the continual balance in medicine between less or more, beneficence and non-maleficence, conservative or invasive, is an ongoing battle.  But when it comes to family, good food, and holidays, more is always better.  We don’t need any evidence to prove that.  Happy Thanksgiving everyone!

Dr. Rhee is a 2nd year resident in internal medicine at NYU Medical Center. 

Faculty peer reviewed by  Michael Tanner MD, Associate Editor, Clinical Correlations

REFERENCES

1. American College of Obstetrics and Gynecology. Cervical Cytology Screening. Obstetrics and Gynecology. Forthcoming December 2009. Available from: http://www.acog.org/from_home/publications/press_releases/nr11-20-09.cfm.

2. Siegel MD, Rubinowitz AN. Routine daily vs. on-demand chest radiographs in intensive care. Lancet. 2009;374(9702)1656-1658.

3. Pfeiffer MA, Birdman EA, Chen C. A trial of darbepoetin alfa in type 2 diabetes and chronic kidney disease. N Engl J Med. 2009;361(21):2019-2032. Available from: http://content.nejm.org/cgi/content/short/361/21/2019.

4. Yu C, Chan JY, Zhang, QM. Biventricular pacing in patients with bradycardia and normal ejection fraction. N Engl J Med [online]. 2009 Nov 15 [cited 2009 Nov 20]. Available from: http://content.nejm.org/cgi/content/full/NEJMoa0907555.

5. Lettieri CJ, Shah AA, Holley AB. Effects of a short course of eszopiclone on continuous positive airway pressure adherence. Ann Intern Med. 2009;141(10):696-702. Available from: http://www.annals.org/content/151/10/696.full.

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