An Epidemiologic Study of the Association between Free Recall Dichotic Digits Test Performance and Vascular Health

Abstract

Associations between vascular health–related factors and hearing loss defined using audiometric pure-tone thresholds have been found. Studies have not focused on a potential relationship between vascular health–related factors and central auditory processing.The aim of this study was to evaluate, on a population level, the relationship of vascular health–related factors with central auditory function.A cross-sectional, population study.Subjects were participants in the Epidemiology of Hearing Loss Study (EHLS) or the Beaver Dam Offspring Study (BOSS)—prospective studies of aging and sensory loss. BOSS participants were the adult offspring of participants in the EHLS. Participants who completed the Dichotic Digits Test (DDT) during the fourth examination period of the EHLS (2008–2010) or the second examination period of the BOSS (2010–2013) were included (n = 3,655, mean age = 61.1 years).The DDT-free recall test was conducted using 25 sets of triple-digit pairs at a 70 dB HL presentation level. The total number of correctly repeated digits from the right and left ears was converted to a percentage correct and used as an outcome. The percentage correct in the left ear was subtracted from the percentage correct in the right ear and used as an outcome. Vascular health–related measures obtained during the examination included blood pressure, mean carotid intima-media thickness, femoral pulse wave velocity (PWV), hemoglobin A1C, and non–high-density lipoprotein (HDL) cholesterol, and, in the EHLS participants, C-reactive protein and interleukin-6. Information on vascular health–related history and behaviors was self-reported. General linear modeling produced estimates of the age- and sex-adjusted least squares means for each vascular factor, and multiple linear regression was used for multivariable modeling of each outcome.After multivariable adjustment, participants with diabetes had a significantly lower (worse) mean DDT-free recall total score (−2.08 percentage points, p < 0.001) than those without diabetes. Participants who exercised at least once per week had a significantly higher (better) mean DDT-free recall total score (+1.07 percentage points, p < 0.01) than those who did not exercise at least once per week. Alcohol consumption was associated with a higher DDT-free recall total score (+0.15 percentage points per +25 g ethanol, p < 0.01). In multivariable modeling of the right–left ear difference in DDT-free recall scores, participants with a history of cardiovascular disease (CVD) or higher PWV demonstrated significantly larger differences (CVD: +3.11 percentage points, p = 0.02; PWV: +0.36 percentage points per 1 m/sec, p < 0.01). Higher levels of non-HDL cholesterol were associated with smaller right–left ear differences (−0.22 percentage points per 10 mg/dL, p = 0.01). Adjustment for handedness did not affect the results.Vascular health–related factors may play a role in central auditory function.

The Associations of Hearing Sensitivity and Different Cognitive Functions with Perception of Speech-in-Noise

“…43,NO. 3,[984][985][986][987][988][989][990][991][992] Our study has some limitations. Due to our cross-sectional design, we were not able to assess the temporal relation between losses in hearing sensitivity, cognitive function, and speech-innoise perception.…”

“…43,NO. 3,[984][985][986][987][988][989][990][991][992] frequency is presented with increasing volume and the participant is instructed to push the button as soon as they perceive the tone. The measurement at that frequency is repeated until two responses are recorded that lie within 5 dB from one another.…”

Effect of Hearing Ability and Mild Behavioural Impairment on MoCA and Memory Index Scores

“…Our LDDT finding is consistent with research showing low left ear scores on dichotic listening tasks linked with MCI and Alzheimer dementia (7,8) and, more recently, a connection with vascular health, lending support to a common etiology linking hearing ability to cognitive and physical functioning. (27)…”

Associations of Hearing Loss and Hearing Aid Use With Cognition, Health-Related Quality of Life, and Depressive Symptoms

“…Body mass index (BMI) was calculated as measured weight in kilograms (kg) divided by measured height in meters (m) squared. History of cardiovascular disease was defined as self-report of a physician-diagnosed stroke, angina, or myocardial infarction (Cruickshanks et al, 2003; Fischer et al, 2019; Zhan et al, 2011). Contrast sensitivity was measured in each eye separately using Pelli–Robson letter charts.…”