Exploring How Blood Cell Levels Influence Subjective Tinnitus: A Cross-Sectional Case-Control Study

<b>Objectives:</b> This study aimed to analyse the haematological parameters in relation to subjective tinnitus. We hypothesise that abnormal haematological findings may correlate with increased severity and chronicity of tinnitus. This research could lead to improved diagnostic methods and more targeted treatments. <b>Material and Methods:</b> A total of 439 patients with primary subjective tinnitus and 274 individuals without tinnitus were enrolled. These participants underwent comprehensive laboratory testing, which included haematological parameters. <b>Results:</b> When comparing the white blood cell levels between the tinnitus group and the control group, no statistically significant differences were found (<i>p</i> = 0.743). Similarly, comparisons of red blood cell levels (<i>p</i> = 0.250), haemoglobin levels (<i>p</i> = 0.087), and haematocrit levels (<i>p</i> = 0.066) also revealed no significant differences. The platelet levels showed no significant difference between the two groups (<i>p</i> = 0.782). According to a logistic regression model, lower levels of haemoglobin (<i>p</i> = 0.000) and platelets (<i>p</i> = 0.000) significantly predicted higher scores on the Tinnitus Handicap Inventory, indicating self-reported tinnitus severity. Furthermore, lower haemoglobin levels were significant predictors (<i>p</i> = 0.04) of developing bilateral tinnitus. Using Spearman's correlation test, a statistically significant negative correlation (<i>p</i> = 0.029) was observed between red blood cell levels and the onset of tinnitus. The frequency of tinnitus demonstrated a significant positive correlation with haemoglobin levels (<i>p</i> = 0.04) and haematocrit levels (<i>p</i> = 0.043). Conversely, platelet levels showed a significant negative correlation with both tinnitus intensity (<i>p</i> = 0.002) and the onset of tinnitus (<i>p</i> = 0.033). <b>Conclusions:</b> While the haematological parameters showed no significant differences between the tinnitus and control groups, further analyses indicated that certain parameters, such as haemoglobin and haematocrit levels, could potentially influence tinnitus, necessitating further investigation.