Correlation between serum lipid and prognosis of idiopathic sudden sensorineural hearing loss: a prospective cohort study

Abstract

Background: To investigate the correlation between blood lipids and the prognosis of idiopathic sudden sensorineural hearing loss (ISSNHL).Methods: We included 232 patients with ISSNHL at the Second Affiliated Hospital of Shanghai University from June 2015 to March 2017 using a prospective cohort study design. We collected information including age, gender, hypertension, diabetes, mellitus, vertigo, as well as the levels of blood total cholesterol (TC), triglycerides (TG), and low-density lipoproteins (LDL-C). We also recorded the ratio between the levels of low-density lipoproteins and the levels of high-density lipoproteins (LDL-C/HDL-C ratio). Correlations between the prognosis of ISSNHL and TC, TG, LDL-C, and LDL-C/HDL-C ratio were analyzed by univariable and multivariable logistic regression analyses.

Update on Findings about Sudden Sensorineural Hearing Loss and Insight into Its Pathogenesis

“…The LDL-C/HDL-C ratio was evaluated in patients with SSNHL to investigate the correlation between the ratio and the degree of hearing recovery. When patients with SSNHL were classified into four groups: complete, partial, slight, and no recovery after treatment, the LDL-C/HDL-C ratio was associated with recovery outcome showing an upward trend from complete recovery to slight recovery group with statistically significant difference [ 30 , 31 ]. Thus, PLR levels and LDL-C/HDL-C ratio were correlated with the prognosis of SSNHL, indicating that the mechanism underlying SSNHL is associated with thrombosis and can lead to vascular obstruction probably in the cochlea.…”

“…The first possible mechanism is thrombosis and resulting vascular obstruction in the cochlea. The markers associated with thrombosis, including PLR and LDL-C/HDL-C ratio, were correlated with the prognosis of SSNHL [ 17 , 26 , 30 , 31 ]. SNPs in thrombosis-related genes, including F2, F5, ITGB3, ITGB2, and MTHFR, were associated with susceptibility to SSNHL [ 8 , 46 , 48 , 50 , 68 ].…”

Thromboelastography predicting the prognosis of sudden sensorineural hearing loss

“…Dyslipidaemia is defined as the elevation of total cholesterol and triglyceride levels, and the ratio of the levels of low‐density lipoprotein cholesterol and high‐density lipoprotein cholesterol is strongly correlated with the prognosis of idiopathic SSNHL. These three indices have been recommended as independent markers to predict prognostic outcomes 7 . However, the aforementioned results are not fully accepted and remain controversial 8 …”

“…These three indices have been recommended as independent markers to predict prognostic outcomes. 7 However, the aforementioned results are not fully accepted and remain controversial. 8 Thromboelastography (TEG) acts as an index to detect dynamic changes in the coagulation process.…”

LDLR expression in the cochlea suggests a role in endolymph homeostasis and cochlear amplification

“…About 80% of daily cholesterol production occurs in the liver and in the intestines, other sites of higher synthesis rates include the brain, the adrenal glands and the reproductive organs ( Luo et al, 2020 ). High serum levels of LDL have been associated with an increased risk of sudden SNHL with poor recovery ( Oreskovic et al, 2011 ;Lin et al, 2015 ;Shao et al, 2021 ;Weng et al, 2013 ;Zhang et al, 2019 ). LDL receptor (LDLR) promotes the endocytosis of cholesterol-rich LDL and thus maintains the plasma level of LDL.…”