Acute palsies may require assessing ischemic risk factors

Montreal-Acute third-, fourth-, or sixth-nerve palsies do not seem to be associated with myocardial infarctions (MI) and cerebrovascular accidents (CVA), but the development of one of these palsies is an indi- cation for an assessment of ischemic risk factors, according to Kashif Baig, MD, MBA.

"Acute isolated palsies of nerves III, IV, and VI commonly occur in older patients, who typically have associated ischemic risk factors. Although these patients recover from their acute palsies, a review of the literature reveals that the cardiovascular and cerebrovascular risk is unknown," explained Dr. Baig, a resident in the Department of Ophthalmology, McGill University Health Centre, here.

He and his colleagues at McGill University Health Centre searched the patient database of the Montreal General Hospital for patients with a diagnosis of diplopia or nerve palsy from January 1996 to July 2001. The search yielded 121 patients with an acute isolated nerve palsy of ischemic origin that resolved or was resolving by 3 months' time. These patients were matched with patients without a palsy by age, gender, and physician. The patients were surveyed by telephone, mail, or both to assess the risk of an MI or a CVA, Dr. Baig explained.

"In determining the prevalence of palsy risk factors, the only risk factors in the study group that reached significance were diabetes and hypertension. For diabetes, the odds of a patient having diabetes were 2.5 times higher than in the control group. Similarly, the odds of a study patient having hypertension were 2 times that of the control patients," Dr. Baig reported.

"Interestingly, after resolution of palsy the relative risk of a patient having an MI is nearly 4 times greater than if the patient had not had a palsy. However, although a higher number of post-palsy MIs was noted, the difference was not significant after adjustment for diabetes and hypertension, which are risk factors for both palsy and MI. This finding suggests that post-palsy patients are not at an increased risk for having an MI," Dr. Baig stated.

The limitations of the study include the retrospective nature and the disproportionately large number of men in the study.

"Our findings suggest that having an acute third-, fourth-, or sixth-nerve palsy is an indication for the assessment of ischemic risk factors. Further cardio- or cerebrovascular work-up is not specifically indicated following the resolution of palsy," he concluded.