Clinical Briefs

By Louis Kuritzky, MD

Prevention of Disabling and Fatal Strokes by Successful Carotid Endarterectomy in Patients without Recent Neurological Symptoms

Clear-cut benefit from carotid endarterectomy for secondary prevention of stroke amongst persons with carotid stenosis who have suffered a stroke/TIA has been well established. Less data is available to lead clinicians towards the best therapeutic choice in persons with asymptomatic carotid stenosis (aCST). The MRC Asymptomatic Carotid Surgery Trial studied patients (n = 3120) with at least 60% stenosis confirmed by ultrasound, in the absence of prior neurologic symptoms suggesting ischemia. Study subjects were enrolled beginning in 1993, and followed for up to 5 years.

When immediate perioperative stroke and death was excluded, the overall 5-year stroke risk was 3.8% in the operative group, versus 11% in the medically managed group. Even when including the perioperative stroke/death risk (= 3.1%), the overall 5-year risk profile supported carotid endarterectomy (stroke rate 6.4% vs 11.8%).

No particular subgroup was noted to have any greater or lesser benefit. For instance, similar benefits were seen in both genders, for all degrees of stenosis greater than 70%, and for all ages up to age 74. For those older than age 74, mortality benefits were notably absent, due to the overriding effect of deaths from other causes.

These data should enhance clinician confidence in the appropriateness of carotid endarterectomy for asymptomatic individuals with greater than 70% stenosis. A critical factor in the decision path will be whether any one clinician’s local surgical outcomes are as excellent as those demonstrated here: a higher perioperative stroke/mortality rate could completely defeat long-term benefits.

MRC Asymptomatic Carotid Surgery Trial Collaborative Group. Lancet. 2004;363:1491-502

Cox-2 Inhibitors vs Nonselective NSAIDs and CHF Outcomes in Elderly Patients

Use of non-selective NSAIDs can induce retention of Na+, K+, and water. Whether selective Cox-2 inhibitors (COXIBs) are fraught with an equally daunting likelihood of potential for fluid and electrolyte imbalance is uncertain. One large study of rofecoxib indicated an increased risk for acute MI, but the implication of these data is much debated. Because many senior adults are receiving either NSAIDs or COXIBs, the relative risk for induction of heart failure (CHF) by these classes of agents is important to discern.

To compare the likelihood of CHF in patients receiving COXIBs, as compared to NSAIDs, Mamdani and colleagues performed a population-based retrospective cohort study of adults over age 66 who had been prescribed rofecoxib (n = 14,583), celecoxib (n = 18,908), NSAIDs (n = 5391), and a control group (non-users of NSAIDs, n = 100,000).

The relative risk for CHF admission amongst recipients of NSAIDs and rofecoxib was increased compared to controls (RR = 1.8 and 1.4, respectively). Celecoxib use was not associated with an increased CHF risk vs control.

NSAIDs are confirmed to increase risk for CHF admission. Amongst COXIBs, celecoxib does not appear to be associated with the same increased CHF risk as rofecoxib.

Mamdani M, et al Lancet. 2004;363: 1751-1756.

Interventions for the Prevention of Falls in Older Adults

One-third of persons older than age 65, and one-half of those older than 80 sustain a fall annually, many of which result in hospital admission, impairment of mobility, or even death. A variety of interventions intended to reduce falls in the elderly have been studied, including exercise, environmental modification, education, and multifactorial risk identification and management.

Chang and associates performed a meta-analysis to evaluate comparative benefits of individual fall-prevention interventions and multifactorial fall risk assessment and management (MFRAM) programs, compared to usual care. A MFRAM was defined as a post-fall evaluation coupled with intervention recommendations and followup. Assessing data from 40 trials, an overall risk reduction of 12% was seen. Meta-regression of individual fall-reduction program components indicated that MFRAM was most effective (NNT = 11), followed by exercise interventions (NNT = 16).

The environmental modification or educational program components of fall prevention did not emerge with a statistically significant favorable effect upon falls. The best investment of effort for fall prevention in seniors appears to be MFRAM and exercise.

Chang JT, et al BMJ USA. 2004;4:223-226.

Dr. Kuritzky, Clinical Assistant Professor, University of Florida, Gainesville, is Associate Editor of Internal Medicine Alert.