The Significance of Bell's Palsy That Presents as Monocranial Versus Polycranial Neuropathy: A Case Series and Systematic Literature Review

Abstract

Purpose To investigate the effect of Bell's palsy (BP) presenting as polycranial neuropathy (PCN) compared with BP caused by isolated facial nerve (CNVII). Methods We carried out a retrospective cohort study of the medical records of all consecutive patients who were diagnosed with BP at a single tertiary referral center between 2010 and 2017. Included were patients 18 years or older who were clinically diagnosed with BP and completed 7 days of systemic steroidal treatment and at least 6 months of follow-up. The patients were divided into two groups according to whether the BP derived from a monocranial neuropathy or a PCN. Demographics and BP severity and outcome were compared between these groups. A systematic literature review using Medline via “PubMed,” “Embase,” and “Web of Science” was conducted. Results In total, 321 patients with BP were enrolled. The median (interquartile range) age at presentation was 44 (33–60) years. Sex distribution showed male predominance of 57.6% (n = 185) versus 42.4% (n = 136), and 21.2% (n = 68) had PCN. The most concomitantly affected cranial nerve (CN) was the trigeminal (CNV; n = 32, 47%), followed by the glossopharyngeal nerve (CNIX; n = 14, 21%) and the audiovestibular nerve (CNVIII; n = 10, 15%). Age, House-Brackmann score on presentation, and diabetes mellitus (DM) were independent predictors for PCN etiology (p = 0.001, p = 0.034, and p < 0.001, respectively). Each increase in 1 year of age was associated with additional odds ratio (95% confidence interval) of 0.97 (0.95–0.99) for PCN. The odds ratio (95% confidence interval) associated with DM was 8.19 (4.02–16.70). Our systematic literature review identified 1,440 patients with the PCN type of BP. The most commonly affected CN was the trigeminus (25–48%), followed by the glossopharyngeal and audiovestibular nerves (2–19% and 0–43%, respectively). Conclusion The severity of facial weakness on initial presentation among PCN patients was significantly higher compared with the monocranial neuropathy–type BP patients. The authors believe that the significant association and prevalence rate ratio between DM and PCN warrant that a patient presenting with PCN undergo screening for DM.

Association between Bell’s Palsy and Cardiometabolic Risks: An Age- and Sex-Matched Case–Control Study

“…However, most of the currently available studies reporting the association between Bell's palsy and the prediabetes state, DM, or MS were cross-sectional studies. [30][31][32][33][34]. With the heterogeneous study population, the settings, the designs, and the length of follow-ups, the reported prevalence of DM in Bell's palsy patients varied from 2.5 to 11% [33,35,36].…”