Examining Older People for Carotid Bruits Listen to Your Patient, Not Her Neck I n teaching and practicing the art of physical diagnosis, we must continually ask: What parts of the physical examination should we keep? And what parts should we County, Georgia, found higher risks of stroke in asymp- tomatic persons with carotid bruit,10,11 and the risk asso- ciated with carotid bruit may decrease with age, especially put on the shelf? Some time-honored elements of the pe- in persons older than 70 years.12 riodic physical examination, such as auscultation of the Nonetheless, Shorr et al. concluded that carotid bruit lungs or measurement of temperature, are of little diag- was not a useful indicator of increased stroke risk in their nostic value when used for screening asymptomatic pa- study population. Several arguments support this conclu- tients.1,2 Other elements of the physical examination also sion. First, many strokes in patients with a unilateral ca- are of little value when we apply them imperfectly—for ex- rotid bruit occurred on the contralateral side and thus ample, when we do not identify a cardiac murmur accu- were unlikely to be related directly to the lesion causing rately or fail to detect an enlarged spleen.3,4 Time spent the bruit. Previous epidemiologic studies have reported teaching or using skills of little value is time we do not similar findings.10,11 These findings are consistent with spend teaching, improving, or practicing skills of greater other findings that the presence of a bruit does not accu- value. In this era of corporate medicine, shortened patient rately reflect the presence of significant stenosis and that visits, and competing demands, our time is precious. the absence of a bruit does not rule out carotid disease.8 Auscultation of the carotid arteries has convention- Second, the association between carotid bruit and stroke ally been part of the physical examination, especially for is confounded by other factors. Figure 1 in the article by older patients because of their increased risk for cere- Shorr et al. provides a classic demonstration of brovascular disease. Should we listen to their carotids confounding13: the relative risk of stroke in patients with routinely? carotid bruit fell when underlying risk of stroke was taken Routine auscultation of the carotids has a compelling into account in a stratified analysis. Finally, the absolute rationale. In the asymptomatic patient, a bruit may indi- risk of stroke associated with carotid bruit was small in cate occult carotid artery stenosis that can be repaired their patients, and it was not statistically significant in surgically before it causes stroke, thus preventing the un- most analyses. Thus, only a slight benefit could be gained suspecting patient from death or crippling stroke. This ra- by repairing carotid stenoses that were found in asymp- tionale is now supported by evidence from an excellent tomatic patients because carotid bruits were detected. clinical trial, the Asymptomatic Carotid Artherosclerosis We agree with Shorr et al. Moreover, the conclusion Study (ACAS), which found that endarterectomy reduced that time should not be wasted listening for carotid bruits the risk over 5 years for ipsilateral stroke, perioperative most likely is generalizable to other asymptomatic patients stroke, or death from 11.0% to 5.1%.5 Nonetheless, de- in the broader population. A recent cost-effectiveness anal- spite the allure of finding a carotid bruit, some authorities ysis used the results of the ACAS, which provides the most have weighed in against screening for carotid disease in favorable information to date on the potential benefits of asymptomatic patients.6–8 screening for asymptomatic carotid disease.7 This analysis In this issue of JGIM, Shorr et al. contribute to our found that ultrasonographic screening of 65-year-old men thinking about the value of searching for asymptomatic would on average extend their quality-adjusted life span by carotid bruits.9 They used data from the landmark Sys- approximately 5 days. The costs associated with this strat- tolic Hypertension in the Elderly Program to study 4,442 egy were so high that routine screening was estimated to community-dwelling persons who were aged 60 years or cost $120,000 per quality-adjusted life-year, which is sub- older and had no history of stroke, transient ischemic at- stantially more than is usually considered acceptable. This tack, or myocardial infarction. The annual rates of stroke conclusion would not be changed substantially by a less were 1.86% in persons who had carotid bruits noted on expensive screening method, such as auscultation, even if enrollment and 1.21% in those without carotid bruits. it were as accurate as ultrasonography. Therefore, the absolute risk of stroke was 0.61% higher In summary, given current data, the time limits of per year in those with carotid bruits compared with those clinical practice, and the greater importance of other risk without carotid bruits, and the relative risk was 1.53 factors such as hypertension and smoking, we cannot (95% confidence interval [CI] 0.98, 2.40). Also, two sub- recommend routine carotid auscultation in asymptomatic groups of patients, those with unilateral bruit and those patients. Rather, we should concentrate our efforts on aged 60 to 69 years, had even higher absolute risks (ap- what we have learned about the efficacy and appropriate- proximately 1% per year) and relative risks (approxi- ness of other medical and surgical interventions to de- mately 2). Although these results did not quite reach the crease the risk of stroke.14 It is now well established that conventional standards of statistical significance, they are aspirin and other platelet inhibitors decrease stroke rates consistent with earlier studies. Prospective, population- modestly in high-risk patients, that warfarin prevents based studies in Framingham, Massachusetts, and Evans most strokes in persons over age 60 who have atrial fibril- 140 JGIM Volume 13, February 1998 141 lation (and that warfarin is more effective than aspirin), 4. Grover SA, Barkun AN, Sackett DL. Does this patient have that antihypertensive drugs lower stroke rates even in splenomegaly? JAMA. 1993;270:2218–21. 5. Executive Committee for the Asymptomatic Carotid Atherosclero- older adults with isolated systolic hypertension, that low- sis Study. Endarterectomy for asymptomatic carotid stenosis. ering the cholesterol level with statins in patients with JAMA. 1995;273:1421–8. coronary heart disease lowers stroke risk as well, and 6. Barnett HJM, Meldrum HE, Eliasziw M. The dilemma of surgical that carotid endarterectomy reduces stroke risk in symp- treatment for patients with asymptomatic carotid disease. Ann In- tomatic persons with more than 70% stenosis. Until we tern Med. 1995;123:723–5. 7. Lee TT, Solomon NA, Heidenreich PA, Oehlert J, Garber AM. Cost- learn more, we should make greater use of these manage- effectiveness of screening for carotid stenosis in asymptomatic ment strategies and not listen for carotid bruits in asymp- persons. Ann Intern Med. 1997;126:337–46. tomatic patients.—LOUISE ARONSON, MD, and C. SETH 8. Sauve JS, Laupacis A, Ostbye T, Feagan B, Sackett DL. Does this LANDEFELD, MD, The Division of Geriatrics and the Center patient have a clinically important carotid bruit? JAMA. 1993; on Aging, University of California San Francisco, and the 270:2843–5. 9. Shorr R, Johnson K, Wan J, et al. The prognostic significance of San Francisco Veterans Affairs Medical Center. asymptomatic carotid bruits in the elderly. J Gen Intern Med. 1998; 13:86–90. 10. Wolf P, Kannel W. Sorlie P, McNamara P. Asymptomatic carotid bruit REFERENCES and risk of stroke. The Framingham study. JAMA. 1981; 245:1442–5. 11. Heyman A, Wilkinson W, Heyden S, et al. Risk of stroke in asymp- 1. DiGuiseppi C, Atkins D, Woolf S, eds. U.S. Preventive Services tomatic persons with cervical arterial bruits: a population study in Task Force. Guide to Clinical Preventive Services. 2nd ed. Alexan- Evans County, Georgia. N Engl J Med. 1980;302:838–41. dria, Va: International Medical Publishing; 1996. 12. Van Ruiswyk J, Noble H, Sigmann P. The natural history of ca- 2. Oboler SK, LaForce FM. The periodic physical examination in rotid bruits in elderly persons. Ann Intern Med. 1990;112:340–3. asymptomatic adults. Ann Intern Med. 1989;110:214–26. 13. Miettinen OS, Cook EF. Confounding: essence and detection. Am 3. Mangione S, Nieman L. Cardiac auscultatory skills of internal J Epidemiol. 1981;114:593–603. medicine and family practice trainees: a comparison of diagnostic 14. Barnett H, Eliasziw M, Meldrum H. Drugs and surgery in the pre- proficiency. JAMA. 1997;278:717–22. vention of ischemic stroke. N Engl J Med. 1995;332:238–48.
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