Prognostic role of neutrophil lymphocyte ratio and mean platelet volume in Bell’s palsy: Comparison of diabetic and non-diabetic patients

OBJECTIVES: A low Neutrophil Lymphocyte Ratio (NLR) has been shown to be associated with good prognosis in Bell’s Palsy (BP). However, the effect of chronic diseases that may affect the NLR, including Diabetes Mellitus (DM), has not been clarified in this context. This study aimed to evaluate the relationship between NLR and Mean Platelet Volume (MPV) in BP according to whether it is accompanied by DM, and their relationship with prognosis. METHODS: A prospective observational study was conducted from May 2014 to May 2020 in a tertiary referral center, of all 79 consecutive participants diagnosed with BP in department of otolaryngology and 110 consecutive healthy participants admitted to the check-up unit. Patients diagnosed with BP were divided into two groups according to whether they were diagnosed with DM: diabetic BP patients (DM-BP, n = 33) and non-diabetic BP patients without any chronic disease (nonDM-BP, n = 46). Neutrophil (NEUT) and Lymphocyte (LYM) counts, and Mean Platelet Volume (MPV) were assessed from peripheral blood samples, and the NLR was calculated. Prognosis was evaluated using the House–Brackmann Score (HBS) six months after diagnosis. RESULTS: The mean NLR was 2.85 ± 1.85 in BP patients and 1.69 ± 0.65 in the control group. The mean NLR was significantly higher in BP patients than healthy controls (p < 0.001). The mean NLR was 2.58 ± 1.83 in the nonDM-BP group, 3.23 ± 1.83 in the DM-BP group, and 1.69 ± 0.65 in the control group. The NLR was significantly higher in the nonDM-BP and DM-BP groups than in the control group (p < 0.05). The recovery was 90% according to the HBS. The optimal cut-off value was 2.41 (p = 0.5). CONCLUSION: The NLR was increased in both diabetic and non-diabetic BP and had similar prognostic value in predicting the HBS before treatment in diabetic and non-diabetic patients with BP. MPV wasn’t significantly different in diabetic and non-diabetic BP patients compared with the normal population.