WHO NEEDS EPILEPSY SURGERY?

Nearly one third of patients who undergo presurgical evaluations for resective epilepsy surgery ultimately do not have this form of surgery, according to a study in the November Epilepsia. This is a group whose needs are not currently met by available therapies and procedures, concluded Anne T. Berg, PhD, of BIOS/NIU in DeKalb, Illinois, and colleagues.

“Lack of clear localizing evidence appears to be the main reason for not having surgery,” the investigators reported. “To the extent that these data can address the question, they suggest that repeated attempts to control intractable epilepsy with new drugs will not result in sustained seizure control, and eligible patients will proceed to surgery eventually.”

A total of 396 patients who had resective surgery were evaluated. Clinical factors such as a well-localized MRI abnormality and consistently localized EEG findings were most strongly associated with having surgery. Of patients who underwent intracranial monitoring (189), 85% went on to have surgery. Race/ethnicity and marital status were marginally associated with having surgery, while age, education, and employment status were not. Demographic factors had little influence on the decision of whether to have surgery.

More than half the patients had intractable epilepsy for 10 years or longer, and five or more drugs had failed by the time the patients had initiated their surgical evaluation. Furthermore, despite an increased availability of new therapeutic options approved during the recruitment period, the proportion of patients who had surgery each year did not fluctuate significantly from year to year. “This suggests that, in this group of patients, the new drugs did not provide a substantial therapeutic benefit,” Dr. Berg and colleagues wrote.

The researchers believe their findings are “consistent with recent arguments to consider surgery earlier rather than later in the course of epilepsy. Postsurgical follow-up of this group will permit a detailed analysis of presurgical factors that predict the best and worse seizure outcomes.”

Dr. Berg’s team also pointed out that although surgical intervention is typically delayed for many years, “our findings suggest that further efforts to control seizures with new drugs in patients for whom numerous other drugs have failed rarely succeed. This tends to give further support to the idea that surgical intervention should be tried earlier in the course of epilepsy once pharmacoresistance has been documented.”

Berg AT, Vickrey BG, Langfitt JT, et al. The multicenter study of epilepsy surgery: recruitment and selection for surgery. Epilepsia. 2003;44:1425-1433.

BILATERAL STIMULATION OF THE SUBTHALAMIC NUCLEUS IN ADVANCED PARKINSON’S DISEASE

Patients with advanced Parkinson’s disease who were treated with bilateral stimulation of the subthalamic nucleus showed marked improvements in motor function within five years while off medication and in dyskinesia while on medication. Paul Krack, MD, PhD, of Joseph Fourier University in Grenoble, France, and colleagues noted that although no control group was used, worsening of akinesia, speech, postural stability, freezing of gait, and cognitive function between the first and fifth year is consistent with the natural course of Parkinson’s disease.

“Our findings show that the efficacy of stimulation of the subthalamic nucleus in reducing off-medication motor symptoms and levodopa-induced dyskinesia in relatively young patients with severe Parkinson’s disease is largely maintained five years after surgery,” the researchers reported in the November 13 New England Journal of Medicine. “However, over time there is deterioration in akinesia, axial symptoms, and cognitive problems that is consistent with the progression of the underlying disease.”

The investigators assessed 49 patients at one, three, and five years with levodopa and without, using the Unified Parkinson’s Disease Rating Scale. They found that, compared with baseline, patients’ scores at five years for motor function while off medication improved by 54%, and those for activities of daily living improved by 49%. Speech was the only motor function for which off-medication scores did not improve. At five years, the dose of dopaminergic treatment and the duration and severity of levodopa-induced dyskinesias were reduced, compared with baseline. The average scores for cognitive performance remained unchanged, although dementia developed in three patients after three years. Mean depression scores did not change; severe adverse events included a large intracerebral hemorrhage in one patient, and one patient committed suicide.

“Stimulation of the subthalamic nucleus seems most useful for relatively young patients who have motor complications from levodopa treatment and who are independent in activities of daily living in their best on-medication state,” wrote Dr. Krack and colleagues. “Those patients who already have disabling motor signs that are resistant to levodopa, or who have cognitive deterioration, are not good candidates for this treatment.”

Krack P, Batir A, Van Blercom N, et al. Five-year follow-up of bilateral stimulation of the subthalamic nucleus in advanced Parkinson’s disease. N Engl J Med. 2003;349:1925-1934.

EFFECTS OF CONCUSSION IN COLLEGIATE FOOTBALL PLAYERS

Two studies appearing in the November 19 JAMA examined the effects of concussion experienced by college football players during the course of three playing seasons. Kevin M. Guskiewicz, PhD, of the University of North Carolina in Chapel Hill, and colleagues found that players with a history of concussions are more likely to have future concussive injuries than are those with no history. In addition, one in 15 football players with a concussion may have additional concussions in the same season, and previous concussions may be associated with slower recovery of neurologic function.

The researchers examined 2,905 football players from 25 US colleges. A total of 184 players had a concussion, and 12 had a repeat concussion within the same season. Players who reported a history of three or more previous concussions were three times more likely to have an incident concussion than were players with no concussion history.

“These results illustrate that a history of previous concussions may be associated with an increased risk of future concussive injuries and that these previous concussions may be associated with slower recovery of neurological function following subsequent concussions,” Dr. Guskiewicz and colleagues reported. “Within a given season, there may be a seven- to 10-day window of increased susceptibility for recurrent concussive injury, but this finding should be further studied in a larger sample of athletes with recurrent in-season concussions.”

Michael McCrea, PhD, of the Waukesha Memorial Hospital in Wisconsin, and colleagues found that collegiate football players may need several days for recovery of symptoms, cognitive dysfunction, and postural instability after a concussion. They evaluated 1,631 football players at 15 US colleges and found that 94 players had a concussion, 79 of whom completed the follow-up protocol at various intervals up to 90 days after the injury. The researchers found that players with concussion exhibited more severe symptoms, cognitive impairment, and balance problems immediately after concussion than did noninjured controls.

Symptoms gradually resolved by day 7, on average, cognitive functioning improved to baseline levels within five to seven days, and balance deficits dissipated within three to five days after injury. No significant differences in symptoms or functional impairments in the concussion and control groups were observed 90 days after concussion.

“Further study is necessary to elucidate factors that predict recovery across all functional domains affected by concussion and to determine the recommended duration of a symptom-free waiting period to minimize the risks associated with recurrent concussion or other adverse outcomes resulting from sport-related head injuries,” Dr. McCrea and colleagues advised.

In an accompanying editorial, Douglas B. McKeag, MD, of the Indiana University School of Medicine in Indianapolis, commented, “[T]hese reports add to the understanding of the natural history of mild traumatic brain injury. In an evidence-based environment, this is an extremely important initial step. The results of these studies, taken in concert with other large studies, have begun to help define what is relevant and important as well as what is critical in the symptom sets that manifest clinically in athletes with brain injuries.”

Guskiewicz KM, McCrea M, Marshall SW, et al. Cumulative effects associated with recurrent concussion in collegiate football players: the NCAA Concussion Study. JAMA. 2003;290:2549-2555.
McCrea M, Guskiewicz KM, Marshall SW, et al. Acute effects and recovery time following concussion in collegiate football players: the NCAA Concussion Study. JAMA. 2003;290:2556-2563.
McKeag DB. Understanding sports-related concussion: coming into focus but still fuzzy. JAMA. 2003;290:2604-2605.

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