Biomaterial Database

Blood viscosity as a factor in sensorineural hearing impairment. 1986

G G Browning, and S Gatehouse, and G D Lowe

The cause of sensorineural hearing impairment is unknown in a high proportion of patients. Since ischaemia is a possible factor, the relation between hearing threshold and blood viscosity, plasma viscosity, and haematocrit was investigated in 49 patients with idiopathic hearing loss, taking into account age, sex, smoking, and socioeconomic group. Hearing thresholds were unrelated to haematocrit or low-shear blood viscosity. Hearing impairment at high frequencies was directly related to high-shear blood viscosity and inversely related to plasma viscosity. The derived measure of red-cell rigidity was significantly related at all frequencies to hearing thresholds. A second study of 92 subjects from a population sample confirmed the inverse relation with plasma viscosity and lack of relation with haematocrit. Increased pure-tone thresholds appear to be related to increased red-cell rigidity; this may be an important factor in sensorineural hearing impairment with implications for diagnosis and prevention.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D008875	Middle Aged	An adult aged 45 - 64 years.	Middle Age
D011446	Prospective Studies	Observation of a population for a sufficient number of persons over a sufficient number of years to generate incidence or mortality rates subsequent to the selection of the study group.	Prospective Study,Studies, Prospective,Study, Prospective
D012044	Regression Analysis	Procedures for finding the mathematical function which best describes the relationship between a dependent variable and one or more independent variables. In linear regression (see LINEAR MODELS) the relationship is constrained to be a straight line and LEAST-SQUARES ANALYSIS is used to determine the best fit. In logistic regression (see LOGISTIC MODELS) the dependent variable is qualitative rather than continuously variable and LIKELIHOOD FUNCTIONS are used to find the best relationship. In multiple regression, the dependent variable is considered to depend on more than a single independent variable.	Regression Diagnostics,Statistical Regression,Analysis, Regression,Analyses, Regression,Diagnostics, Regression,Regression Analyses,Regression, Statistical,Regressions, Statistical,Statistical Regressions
D001809	Blood Viscosity	The internal resistance of the BLOOD to shear forces. The in vitro measure of whole blood viscosity is of limited clinical utility because it bears little relationship to the actual viscosity within the circulation, but an increase in the viscosity of circulating blood can contribute to morbidity in patients suffering from disorders such as SICKLE CELL ANEMIA and POLYCYTHEMIA.	Blood Viscosities,Viscosities, Blood,Viscosity, Blood
D004912	Erythrocytes	Red blood cells. Mature erythrocytes are non-nucleated, biconcave disks containing HEMOGLOBIN whose function is to transport OXYGEN.	Blood Cells, Red,Blood Corpuscles, Red,Red Blood Cells,Red Blood Corpuscles,Blood Cell, Red,Blood Corpuscle, Red,Erythrocyte,Red Blood Cell,Red Blood Corpuscle
D005260	Female		Females
D006319	Hearing Loss, Sensorineural	Hearing loss resulting from damage to the COCHLEA and the sensorineural elements which lie internally beyond the oval and round windows. These elements include the AUDITORY NERVE and its connections in the BRAINSTEM.	Deafness Neurosensory,Deafness, Neurosensory,Deafness, Sensoryneural,Neurosensory Deafness,Sensorineural Hearing Loss,Sensoryneural Deafness,Cochlear Hearing Loss,Hearing Loss, Cochlear,Deafnesses, Neurosensory,Deafnesses, Sensoryneural,Neurosensory Deafnesses,Sensoryneural Deafness,Sensoryneural Deafnesses
D006400	Hematocrit	The volume of packed RED BLOOD CELLS in a blood specimen. The volume is measured by centrifugation in a tube with graduated markings, or with automated blood cell counters. It is an indicator of erythrocyte status in disease. For example, ANEMIA shows a low value; POLYCYTHEMIA, a high value.	Erythrocyte Volume, Packed,Packed Red-Cell Volume,Erythrocyte Volumes, Packed,Hematocrits,Packed Erythrocyte Volume,Packed Erythrocyte Volumes,Packed Red Cell Volume,Packed Red-Cell Volumes,Red-Cell Volume, Packed,Red-Cell Volumes, Packed,Volume, Packed Erythrocyte,Volume, Packed Red-Cell,Volumes, Packed Erythrocyte,Volumes, Packed Red-Cell
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man