Dott. Paolo Balzaretti

 

Acute idiopathic facial paralysis, which is frequently referred to with the eponym of Bell’s Palsy, has an incidence of about 53 cases/100.000 persons/year in Italy (1). It is frequently encountered in the Emergency Department because usually characterized by the acute onset of concerning symptoms involving the facial district.

Recommended therapy consisted for long time in anti-viral drugs and corticosteroids. Recently the former has been questioned because of unclear of efficacy in milder cases, as demonstrated by recent reports in literature (2). On the other side, the use of corticosteroids is still supported by good evidence, taken into account in the specialty guidelines proposing the following recommendations:

• “Clinicians should prescribe oral steroids within 72 hours of symptom onset for Bell’s palsy patients 16 years and older” (American Academy of Otolaryngology—Head and Neck Surgery Foundation Guidelines 2013 [3]);
• “We recommend the use of corticosteroids for all patients with Bell palsy” (Canadian Society of Otolaryngology – Head and Neck Surgery and Canadian Neurological Sciences Federation Guidelines 2014 [4]).

The American guidelines (3) suggest a 10-day course of oral steroids with at least 5 days at a high dose (either prednisolone 50 mg for 10 days or prednisone 60 mg for 5 days followed by a 5-day taper), initiated within 72 hours of symptom onset.

To further explore this clinical area, the Cochrane Collaboration has published the systematic review we are going to summarize (5).

 

Title: Corticosteroids for Bell’s Palsy (idiopathic facial paralysis).

Authors: Madhok VB, Gagyor I, Daly F, Somasundara D, Sullivan M, Gammie F, Sullivan F.

Bibliographic citation: Cochrane Database Syst Rev 2016;(7): CD001942. DOI: 10.1002/14651858.CD001942.pub5.

Objective: Evaluate effectiveness and safety of corticosteroid therapy in people with Bell’s palsy.

Included studies: randomized or quasi randomized trials comparing corticosteroids with placebo or no therapy.

Primary outcome: Incomplete recovery of facial motor function six months or more after randomization.

Secondary outcomes: cosmetically disabling persistent sequelae of facial paralysis six or more after randomization, corticosteroids therapy related adverse effects.

Number of included studies: 7; from studies evaluating multiple treatment strategies, just the placebo and the corticosteroids-only arms were taken into account.

Quality of included studies: overall quality of studies was good. Regarding biases, most concerning areas were incomplete outcome data and blinding of outcome assessment. Two trials included were presented poor quality, Austin 1993 and Unuvar 1999.

Number of patients: 895, 461 from a single study (Engstrom 2008).

 

 

Outcome	No. of patients / No. of studies	Risk ratio (95% C.I.)	Quality of evidence
Incomplete recovery 6 months or more after randomization (2)	895 / 7	0,63 (0,50 - 0,80)	High
Cosmetically disabling persistent sequelae of facial paralysis six or more after randomization	75 / 2	0,96 (0,40 – 2.29)	Low
Corticosteroids therapy related adverse effects	715 / 3	1,04 (0,71 – 1.51)	Moderate

 

Table 1. Synthesis of the results. Recover was evaluated using the House-Brackmann score (6).

 

This systematic review confirms the good results of previously published studies: Salinas et al, found a risk ratio of 0,71 (C.I. 95% 0,61-0,83) in a systematic review including also adrenocorticotrophic hormone therapy (7). Even considering the higher bound of the confidence interval, we can still observe a favorable risk/benefit profile for the administration of corticosteroids. For the primary outcome, low heterogeneity was found (I2 = 18%).

A first limitation of the study is the high risk of bias regarding blinding of outcome assessment; this is particularly concerning mainly because to define the primary outcome was used the House-Brackmann Score, a scoring system based on a subjective evaluation of the facial nerve function (5).

Another weakness is related to the wide variability of the therapeutic regimens tested, ranging from prednisone 50 mg daily po to 1 g daily intravenously. However, 83% of the patients were treated with a total daily dose of 50 to 60 mg of prednisone/prednisolone, justifying the dosage recommendation issued by the American Academy of Otolaryngology—Head and Neck Surgery Foundation Guidelines (3). Though, sensitivity analyses would have been of interest to analyze a dose-response correlation.

Both cited guidelines state that benefit of treatment is stronger if started soon after onset of symptoms (48-72 hours) (3, 4) but no subgroup analyses we’re reported even for this question.

In summary, this systematic review confirms the usefulness of corticosteroids in patients with Bell’s palsy; more data about the correlation about early treatment and outcome would be useful for emergency medicine practitioners to further refine clinical management.