Differences in platelet-related parameters among patients with audiographically distinct sudden sensorineural hearing loss: A retrospective study

We explored possible relationships between sudden sensorineural hearing loss (SSNHL) in patients differing in terms of audiographic data and the levels of vascular markers in routine blood data. We included 37 patients with low-frequency SSNHL (LF-SSNHL), 28 with high-frequency SSNHL (HF-SSNHL), 32 with all-frequency SSNHL (AF-SSNHL), 32 with total-deafness SSNHL (TD-SSNHL), and 31 age- and sex-matched healthy controls. Peripheral venous blood samples were collected, and routine blood parameters including platelet and lymphocyte count, mean platelet volume (MPV), and platelet-to-lymphocyte ratio (PLR) were measured. Each group was divided into recovery subgroup and unrecovery subgroup in accordance with hearing level after 1 month therapy, then compared the difference of platelet and lymphocyte count, MPV, and PLR between the 2 subgroups. No significant difference was observed between platelet count of all SSNHL patients and control group (all P > .05). MPV of AF-SSNHL and TD-SSNHL, PLR of all SSNHL patients were significantly higher than those of control group (all P < .05), while lymphocyte count of all audiographically distinct SSNHL patients was significantly lower than that of control group (all P < .05). However, the difference of platelet count, lymphocyte count, MPV, and PLR among audiographically distinct SSNHL patients was not significant (all P > .05). In HF-SSNHL patients, lymphocyte count of unrecovery subgroup was significantly lower, while MPV and PLR of the unrecovery subgroup were significantly higher than those of recovery subgroup (all P < .05). In AF-SSNHL patients, MPV of the unrecovery group was significantly higher than that of recovery subgroup (P < .05). Lymphocyte count, MPV, and PLR may be relative to SSSNHL, but they could not be used to distinct SSNHL audiographically. Lower lymphocyte, higher MPV, and PLR may be indicative for the prognosis of HF-SSNHL patients; higher MPV may be related to bad treatment outcome of AF-SSNHL patients.