Bell's palsy: a manifestation of prediabetes?

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

BACKGROUND

Bell's palsy is possibly an ischemic cranial neuropathy, although reactivation of herpes virus infection has been proposed.

METHODS

This was an age-and sex-matched and 1:2 case-control study enrolling Bell's palsy patients during 2011-2021 in a university hospital to investigate the significant associations of cardiometabolic risks (CMRs) with Bell's palsy. We analyzed the differences in waist circumference (WC), body mass index (BMI), systolic and diastolic blood pressures (SBP and DBP), fasting blood sugar (FBS), and lipid levels at 12 weeks post-Bell's palsy with those of the controls by descriptive statistics (p < 0.05). The differences in means or medians of individual CMR values across the consecutive 10-year age intervals were analyzed by ANOVA F-tests and Kruskal-Wallis tests (p < 0.05).

RESULTS

A total of 140 cases and 280 controls were enrolled. Bell's palsy patients had significantly higher WC, BMI, SBP, DBP, FBS, and triglyceride but lower high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C). Moreover, high WC, elevated FBS (≥100 mg/dL), SBP (≥130 mmHg), and total cholesterol were significantly associated with Bell's palsy cases by multivariable analysis. Only FBS in Bell's palsy patients significantly elevated across consecutive 10-year age intervals.

CONCLUSION

Screening and monitoring for CMRs, especially hyperglycemia, in every patient presenting with Bell's palsy is essential despite initial normoglycemia, particularly in older-onset cases.

The Effects of Andrographis paniculata (Burm.F.) Wall. Ex Nees and Andrographolide on Neuroinflammation in the Treatment of Neurodegenerative Diseases

Neurodegenerative diseases (NDs) affect millions of people worldwide, and to date, Alzheimer's and Parkinson's diseases are the most common NDs. Of the many risk factors for neurodegeneration, the aging process has the most significant impact, to the extent that it is tempting to consider neurodegenerative disease as a manifestation of accelerated aging. However, genetic and environmental factors determine the course of neurodegenerative disease progression. It has been proposed that environmental stimuli influence neuroplasticity. Some clinical studies have shown that healthy lifestyles and the administration of nutraceuticals containing bioactive molecules possessing antioxidant and anti-inflammatory properties have a preventive impact or mitigate symptoms in previously diagnosed patients. Despite ongoing research efforts, the therapies currently used for the treatment of NDs provide only marginal therapeutic benefits; therefore, the focus is now directly on the search for natural products that could be valuable tools in combating these diseases, including the natural compound Andrographis paniculata (Ap) and its main constituent, andrographolide (Andro). Preclinical studies have shown that the aqueous extract of Ap can modulate neuroinflammatory and neurodegenerative responses, reducing inflammatory markers and oxidative stress in various NDs. Therefore, in this review, we will focus on the molecular mechanisms by which Ap and Andro can modulate the processes of neurodegeneration and neuroinflammation, which are significant causes of neuronal death and cognitive decline.

Diabetes Mellitus and Bell's Palsy

The aim of the present brief review was to discuss Bell's palsy (BP) in diabetes mellitus (DM). The risk of BP is increased in DM. DM subjects with BP are more prone to severe facial nerve degeneration. Further characteristics of BP in DM include a) infrequent taste impairment; b) more frequent and more marked facial nerve subclinical electrophysiological impairment; c) more frequent Blink reflex impairment; d) potentially concurrent distal symmetrical sensorimotor polyneuropathy; e) more frequent alternating BP with recurrent episodes affecting different sides of the face. Diagnosis of BP rests on clinical examination, along with facial nerve electromyographic and electroneurographic evaluation. Management of BP in DM includes physical therapy, corticosteroids, and antiviral agents. Finally, acupuncture, low-level laser therapy, lipoprostaglandin E1, and stellate ganglion block are new modalities with initially promising results.

Evaluation of Effects of Diabetes Mellitus, Hypercholesterolemia and Hypertension on Bell's Palsy

The aim of this study is to evaluate the effects of diabetes mellitus, hypertension and hypercholesterolemia on the clinical presentation and outcome of Bell’s palsy. The study (comorbidity) group consisted of 50 patients with Bell’s palsy associated with diabetes, hypertension, or hypercholesterolemia; the control group included 46 patients with Bell’s palsy, but without comorbid diseases. The House–Brackmann grading system (I to VI) was used in order to assess the initial and final facial functions. Both groups of patients were treated with steroids and the antiviral agent acyclovir. The mean severity of initial facial paralysis was more significant in diabetes, hypercholesterolemia, and hypertension, in comparison to the control group. Patients suffering from Bell’s palsy and concomitant comorbidities have a poorer prognosis (HB III-VI) compared to patients without comorbidities. Increased glycosylated hemoglobin A1c levels (>6.7%) were significantly correlated with unsatisfactory facial recovery. The pathogenetic mechanisms by which diabetes, hypercholesterolemia, and hypertension affect the vasa nervosum of facial nerve have been described.

Prognostic role of homeostasis model assessment and oral glucose tolerance test in nondiabetic patients with Bell’s palsy

Background/aim

We aimed to reveal the incidence and predictive role of insulin resistance and distorted oral glucose tolerance test in nondiabetic patients with Bell’s Palsy (BP).

Materials and methods

Eighty-six patients with BP and 28 control subjects; all with normal blood glucose levels and no history of diabetes, were enrolled in the study. We investigated insulin resistance (IR) in all subjects, in terms of HOMA-IR greater than 2.7. Sixty-two of the patients also underwent an oral glucose tolerance test (OGTT).

Results

The mean HOMA-IR value was significantly increased in patients, compared to the control group (3.2 vs 1.6; P < 0.01). IR was detected more in BP patients than in controls (P < 0.05). The patients with higher HOMA-IR values had more severe facial dysfunction at the initial presentation and complete recovery time took longer than the patients with normal HOMA-IR value (75 days vs 42 days; P < 0.05). Following a 2h-OGTT, impaired glucose tolerance and newly diagnosed DM were found in 60% of the patients. Recovery time was significantly longer in prediabetics and newly diagnosed diabetic patients than in patients with normal glycemia (68 days, 52 days, and 32 days, respectively; P < 0.01).

Conclusion

There is a strong linkage between HOMA-IR value and BP prognosis so HOMA-IR value may have a significant role of predicting BP prognosis at presentation.

The etiology of Bell's palsy: a review

Bell’s palsy is the most common condition involving a rapid and unilateral onset of peripheral paresis/paralysis of the seventh cranial nerve. It affects 11.5–53.3 per 100,000 individuals a year across different populations. Bell’s palsy is a health issue causing concern and has an extremely negative effect on both patients and their families. Therefore, diagnosis and prompt cause determination are key for early treatment. However, the etiology of Bell’s palsy is unclear, and this affects its treatment. Thus, it is critical to determine the causes of Bell’s palsy so that targeted treatment approaches can be developed and employed. This article reviews the literature on the diagnosis of Bell’s palsy and examines possible etiologies of the disorder. It also suggests that the diagnosis of idiopathic facial palsy is based on exclusion and is most often made based on five factors including anatomical structure, viral infection, ischemia, inflammation, and cold stimulation responsivity.

Diabetes in the practice of otolaryngology

Diabetes mellitus is the most common endocrine disease, characterized by chronic hyperglycemia. The hyperglycemic milieu leads to endothelial injury in blood vessels of variant size, which results in microangiopathy and macroangiopathy (atherosclerosis). Consequential ischemia of nerves and hyperglycemia by itself lead to nerve degeneration and generalized neuropathy, affecting most often the sensory peripheral nerves and the autonomic nervous system. Auditory, vestibular and olfactory sensorium may be compromised by DM. People with DM have an increased susceptibility to infection, as a result of neutrophil dysfunction and impaired humoral immunity. Therefore DM predisposes to certain infectious diseases, such as fungal sinusitis or malignant otitis externa, which are rare in general population. Recovery from infections or from injuries may be compromised by coexisting DM. In this review we discuss complications of DM in the head and neck region. Otolaryngologists and general practitioners should be alert to specific conditions related to DM and be minded of the relevant complications and consequences.

Does Type 2 Diabetes Mellitus Affect the Healing of Bell's Palsy in Adults?

OBJECTIVES

Bell's palsy (BP) is defined as an acute facial weakness of unknown cause. Many factors affecting the healing of BP have been identified; 1 factor commonly considered relevant is the presence of type 2 diabetes mellitus. Our aim was to investigate the effects of diabetes on the healing of BP.

METHODS

Sixty patients with BP were followed up for 1 to 3 years and were divided into 2 groups, those with and those without type 2 diabetes. All were prescribed prednisone (initially 1 mg/kg per day, with a tapered dose reduction) and acyclovir (200 mg orally every 4 h, 5 times daily, for 5 days). Their recovery times were compared.

RESULTS

The healing times of the patients with and without diabetes did not differ.

CONCLUSIONS

Diabetes does not affect the severity, recovery rate from or healing of BP.

Cognitive impairment is correlated with insulin resistance degree: the "PA-NICO-study"

Several epidemiological studies have shown that Diabetes Mellitus (DM) or Insulin Resistance (IR) increases the risk of dementia. Besides, some authors suggested that poor glucose control to be associated with worse cognitive function. We aimed to assess cognitive functions and IR-degree over time in diabetic. We also evaluated whether a greater magnitude of cognitive decline could be related with their IR degree. We enrolled 335 diabetic patients and 142 non-diabetic subjects; participants were subdivided into three groups in accordance with their IRdegree assessed by Homa-Index (HI): Normal-HI (non-diabetic NHI < 2,6), Moderate-HI (MHI > 2,6 < 10) and High-HI (HHI > 10). Metabolic status and a comprehensive neuropsycological test battery (MMSE, ADAS-Cog, ACDS-ADL) were assessed at baseline and every 12-months during the follow-up (6,8 years). At the end of the study, the average MMSE decreased significantly in patients of HHI group (P = .001) compared to baseline. MMSE scores were also reduced both in MHI group and in controls, but the difference between two groups was not significant. In HHI group, similar effects were observed for the ADAS-Cog score compared to baseline (P = 0.001); instead, when ACDS-ADL was evaluated, no differences was observed among the three groups. These results remained unchanged also after adjustment for confounding variables (i.e. APOε-status, sex, BMI, education level, heart diseases and HbA1c). We suggest that higher IR-degree is associated with greater cognitive decline in diabetic patients; so we hypothesize that IR degree, more than IR status itself, could be related to the severity of cognitive impairment.

Facial nerve palsy after reactivation of herpes simplex virus type 1 in diabetic mice

OBJECTIVES/HYPOTHESIS

Bell's palsy is highly associated with diabetes mellitus (DM). Either the reactivation of herpes simplex virus type 1 (HSV-1) or diabetic mononeuropathy has been proposed to cause the facial paralysis observed in DM patients. However, distinguishing whether the facial palsy is caused by herpetic neuritis or diabetic mononeuropathy is difficult. We previously reported that facial paralysis was aggravated in DM mice after HSV-1 inoculation of the murine auricle. In the current study, we induced HSV-1 reactivation by an auricular scratch following DM induction with streptozotocin (STZ).

STUDY DESIGN

Controlled animal study.

METHODS

Diabetes mellitus was induced with streptozotocin injection in only mice that developed transient facial nerve paralysis with HSV-1. Recurrent facial palsy was induced after HSV-1 reactivation by auricular scratch.

RESULTS

After DM induction, the number of cluster of differentiation 3 (CD3)(+) T cells decreased by 70% in the DM mice, and facial nerve palsy recurred in 13% of the DM mice. Herpes simplex virus type 1 deoxyribonucleic acid (DNA) was detected in the facial nerve of all of the DM mice with palsy, and HSV-1 capsids were found in the geniculate ganglion using electron microscopy. Herpes simplex virus type 1 DNA was also found in some of the DM mice without palsy, which suggested the subclinical reactivation of HSV-1.

CONCLUSIONS

These results suggested that HSV-1 reactivation in the geniculate ganglion may be the main causative factor of the increased incidence of facial paralysis in DM patients.

The neurologist's dilemma: a comprehensive clinical review of Bell's palsy, with emphasis on current management trends

Background

Recent advances in Bell’s palsy (BP) were reviewed to assess the current trends in its management and prognosis.

Material/Methods

We retrieved the literature on BP using the Cochrane Database of Systematic Reviews, PubMed, and Google Scholar. Key words and phrases used during the search included ‘Bell’s palsy’, ‘Bell’s phenomenon’, ‘facial palsy’, and ‘idiopathic facial paralysis’. Emphasis was placed on articles and randomized controlled trails (RCTs) published within the last 5 years.

Results

BP is currently considered the leading disorder affecting the facial nerve. The literature is replete with theories of its etiology, but the reactivation of herpes simplex virus isoform 1 (HSV-1) and/or herpes zoster virus (HZV) from the geniculate ganglia is now the most strongly suspected cause. Despite the advancements in neuroimaging techniques, the diagnosis of BP remains one of exclusion. In addition, most patients with BP recover spontaneously within 3 weeks.

Conclusions

Corticosteroids are currently the drug of choice when medical therapy is needed. Antivirals, in contrast, are not superior to placebo according to most reliable studies. At the time of publication, there is no consensus as to the benefit of acupuncture or surgical decompression of the facial nerve. Long-term therapeutic agents and adjuvant medications for BP are necessary due to recurrence and intractable cases. In the future, large RCTs will be required to determine whether BP is associated with an increased risk of stroke.