This was a cross-sectional, population-based study. We performed
retinal photography and pure-tone audiometry on 1511 older individuals (ages 54+ years) from the Blue Mountains Eye Study population. Examination of the
retinal microvasculature provides a noninvasive means of assessing systemic microvascular changes associated with
cardiovascular disease, especially since reliable methods of quantifying
retinal microvascular abnormalities from
retinal photographs have recently been developed. Trained graders masked to audiometry data assessed
retinal photographs for signs of
retinal microvascular damage, for example, focal arteriolar narrowing, arteriovenous nicking, and retinopathy (
microaneurysms, retinal hemorrhages), and used a computer-assisted method to measure arteriolar and venular calibers. We defined moderate or profound
hearing loss as pure-tone average air-conducted hearing thresholds in the better ear worse than 40 dB at 0.5, 1, 2, and 4 kHz. We used odds ratios (OR), 95% confidence intervals (CI), and probability values to present the associations between
retinal microvascular abnormalities and
hearing loss; an OR >1 indicates that persons with the microvascular abnormality are more likely to have
hearing loss, a CI that includes 1.00 (e.g., 0.85 to 2.34) indicates no statistically significant association (i.e., the association may have occurred due to chance), whereas a value of p < 0.05 indicates that an association is unlikely to have occurred due to chance.
RESULTS: The proportion of women and men with moderate or profound
hearing loss was 10.4% (90/862) and 15.4% (100/649), respectively. After adjustment for age, sex, blood pressure, and other risk factors for
hearing loss, retinopathy in women was associated with
hearing loss (adjusted OR, 2.10; 95% CI, 1.09 to 4.06, p = 0.002) but not in men. Associations were stronger for moderate or worse low-frequency (0.25 to 1.0 kHz)
hearing loss in women (adjusted OR, 3.00; 95% CI, 1.25 to 7.19, p = 0.0005) but were absent for
high-frequency hearing loss. In men, no
retinal microvascular abnormalities were associated with
hearing loss at either low or high frequencies.
CONCLUSIONS: Retinopathy, a sign of
retinal microvascular damage, was associated with
hearing loss in women but not in men. Our results provide modest support to the hypothesis that microvascular disease may play a role in age-related
hearing loss in women, particularly low-frequency losses.