From Medscape Medical News
Allison Gandey
September 3, 2009 — Results from a systematic review suggest that adding an antiviral to corticosteroid therapy for Bell's palsy might increase efficacy. Antivirals as single agents have proven unsuccessful in activating the cranial nerve, so many doctors use them instead in combination with steroids. But the practice is mired in uncertainty and has prompted questions that investigators worked to answer in a meta-analysis published September 2 in the Journal of the American Medical Association.
"The most important point is that we found the use of steroids early in Bell's palsy is effective," study author Gordon Guyatt, MD, from McMaster University in Hamilton, Ontario, said during an interview.
In contrast to the primary trials, the new meta-analysis suggests that antivirals might be beneficial when combined with steroids. "Everyone had concluded that there is no place for antivirals, but our work suggests the possibility of an even bigger effect," Dr. Guyatt told Medscape Neurology. "Our study emphasizes the importance of comprehensive statistical reviews."
Although the results point to a possible incremental benefit, the investigators acknowledge that the relative risk of 0.75 did not reach statistical significance (P = .05). It is a problem that leaves much to clinical decision-making between doctors and patients until more studies are done.
Failed to Reach Statistical Significance
The results conflict with a small meta-analysis published in June (Arch Otolaryngol Head Neck Surg. 2009;135:558-564). In that study, investigators looked at just 4 studies and concluded that no treatment is established in Bell's palsy.
But after reviewing 18 randomized controlled trials of more than 2700 patients, Dr. Guyatt and his team, led by John de Almeida, MD, from Sunnybrook Hospital in Toronto, Ontario, disagree with that study. They report that corticosteroids were associated with a reduced risk for unsatisfactory recovery (relative risk, 0.69; 95% confidence interval, 0.55 to 0.87; P = .001). They found the number needed to treat to benefit 1 person is 11.
"This evidence is not likely to be contradicted by additional clinical trials," John Steiner, MD, from Kaiser Permanente Colorado in Denver, said in an accompanying editorial. "It has important implications for clinical practice."
"Corticosteroids are well established," Dr. Guyatt said.
Corticosteroids Standard, Antivirals Debatable
In their June paper, Drs. John Goudakos and Konstantinos Markou, from AHEPA University Hospital and Aristotle University of Thessaloniki in Greece, said that "treatment decisions regarding patients with Bell's palsy are doubtful and remain a common problem in medical practice."
Many questions remain when it comes to whether to experiment with combination therapy. "Given the possibility of marginal benefit and the absence of major harm with antiviral therapy, clinicians may convert uncertain knowledge into definitive action by adding an antiviral medication to a corticosteroid for their next patient with Bell's palsy," Dr. Steiner noted.
"Until the next generation of clinical trials is completed, clinicians and patients will have to deal with substantial uncertainty in deciding whether to add antiviral drugs to corticosteroids." But, he adds, the availability of generic low-cost antivirals, such as acyclovir, and the apparent absence of major adverse effects suggest that large clinical trials are warranted.
The authors agree that more trials are needed, but they disagree with Dr. Steiner on the issue of cost. At roughly $20 a day for acyclovir (4000 mg) and valacyclovir (3000 mg), the price is "not insignificant," they note — especially for an uncertain benefit.
Coauthor Ian Witterick, MD, from Mount Sinai Hospital in Toronto, Ontario, reports receiving funding from Schering, Abbott Laboratories, and Alcon Canada.
JAMA. 2009;302:985-993. Abstract
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