Bell’s Palsy Medical Management – Antivirals, Steroids, Both or Neither?
Search Strategy: You conduct a PUBMED Clinical Query using a narrow search strategy for therapy and the search term “Bell’s palsy” to obtain 41 citations including all four of the meta-analyses below. To reproduce this search strategy see http://tinyurl.com/2cff8ku
After administering thrombolytics via the NINDS protocol to your first acute ischemic stroke patient within 2.5-hours of symptom onset, your pulse begins to return to normal as you look over the remainder of the trauma bay patients. Walking into a double-booked Room #6 in TCC you see healthy (no PMH) 25-year old Mr. Y (right) who notes waking up with altered left-sided facial sensation. He notes no associated headache, photophobia, visual changes, sore throat, toothache, or fever. Aside from a dry left eye and abnormal tasting food, he notes no He has not had any recent head or facial trauma and denies any prior episodes of Bell’s Palsy. When he smiles, you note left sided weakness that includes the forehead suggesting the diagnosis of Bell’s Palsy which you report to your attending along with your rationale for excluding other diagnoses such as acute ischemic stroke. The attending asks you how you want to treat Mr. Y.
In addition to artificial tears and night-time eye protection, Up-to-Date suggests combined therapy for severe facial palsy with Valacyclovir (1000 mg TID) and prednisone (60-80 mg daily) for one-week. However, the Up-to-Date review prefaces their recommendations with two large trials suggesting no benefit for Bell’s Palsy patients with anti-viral agents. Since you just finished reading Overtreated, Shannon Brownlee’s treatise about American medicine’s zealous reliance upon pharmaceuticals and technology, you decide to independently explore the issue.
Population: Adult ED patients with idiopathic unilateral facial weakness suggesting Bell’s Palsy
Intervention: Oral steroids plus anti-viral therapy
Comparison: Oral steroids alone or placebo
Outcome: Facial weakness recovery rates and speed to resolution, medication side effects, cost-effectiveness
Article 1: Corticosteroids for Bell’s palsy (idiopathic facial paralysis) Cochrane Database of Systematic Reviews 2010, Issue 3. Art. No.: CD001942
Article 2: Antiviral treatment for Bell’s palsy (idiopathic facial paralysis) Cochrane Database of Systematic Reviews 2009; Issue 4, Art No. CD001869
Article 3: Combined Corticosteroid and Antiviral Treatment for Bell Palsy: A Systematic Review and Meta-analysis JAMA 2009; 302:985-933
Article 4: The benefits of steroids versus steroids plus antivirals for treatment of Bell’s palsy: a meta-analysis, BMJ 2009; 339:b3354:1-7
Bell’s Palsy accounts for 60%-70% of unilateral facial weakness. With an incidence of 30 cases per 100,000 per year and a U.S. population of 380 million, that equates to 114,000 cases of Bell’s Palsy per year. If a 10-day course of anti-viral agents costs $25 than treating all new cases of Bell’s Palsy in the U.S. each year would cost $2.85 million. Cost-effectiveness analyses have previously demonstrated that treatment of Bell’s Palsy with steroids is cost-effective, but anti-viral agents are not. Several characteristics are associated with a poor prognosis for full recovery from Bell’s Palsy: older age, pre-existing hypertension, associated taste impairment, facial pain (other than in the ear), and complete facial paralysis. These prognostic predictors might be considered when assessing the utility of steroids and/or anti-viral therapy for individual patients. Bell’s Palsy is rarely recurrent, so if you see a recurrent case think myasthenia gravis or structural lesions within the pons. The differential diagnosis of Bell’s Palsy includes diabetes mellitus, HTN, HIV, Lyme disease, Ramsay Hunt syndrome, sarcoidosis, Sjogren’s syndrome, parotid nerve tumors, eclampsia, and amyloidosis.
All of the randomized controlled trials rely upon one of three metrics (House-Brackmann, Sunnybrook, or the Yanagihara) to assess clinician-rated facial asymmetry at some interval after diagnosis (usually < 1 year). Although these instruments are reliable and generally agree with one another, none of them has been assessed against patient-important outcomes such as self-perceived disfigurement or post-Bell’s Palsy facial pain.
Electrical nerve studies suggest that when excitability is retained at between day 4 & 10, 90% of patients will recover completely. Only 20% will recover completely when electrical excitability is not retained. Other EBM groups have assessed the risks & benefits of these two agents. Most agree that anti-virals offer little to no benefit while steroids will benefit about 10% of patients. However, some studies suggest that as many as 1-in-231 patients will be harmed by steroids with an intracranial hemorrhage, although this is not a uniform finding across studies.
Here’s our perspective based upon the current meta-analyses:
In adults with Bell’s palsy less than 72-hours after symptom onset, steroids improve the likelihood of complete facial recovery (NNT 10 but I2 = 55%) and reduce rates of motor synkinesis/autonomic dysfunction at six months (NNT 12, I2 0%) without significant adverse effects. Future trials will need to assess the optimal timing, steroid, dosing, and duration to achieve benefit. In the meantime there is no apparent reason not to use a single corticosteroid for 10 – 14 days in adult Bell’s palsy patients presenting within three days in onset. The JAMA SR included non-peer reviewed research abstracts and noted that corticosteroids alone reduce poor cosmetic outcome rates (NNT = 11) and synkinesis crocodile tears (NNT 7). Steroids should be used in doses exceeding 450 mg equivalent of prednisolone.
Available research data, including seven high quality trials of 1987 patients, do not suggest a benefit for anti-herpetic agents (acyclovir, valacylovir, famciclovir) in the acute management of Bell’s palsy. The one exception may be the subset with complete unilateral facial paralysis on presentation in which case recovery rates may improve with antivirals and steroids vs. steroids alone. Future trials will need to assess the role of antivirals this subset in addition to patient-oriented outcomes like QOL and perceived disability.