The association between reduced GFR and hearing loss: a cross-sectional population-based study.

BACKGROUND: Chronic kidney disease (CKD) has long been associated with hearing loss in certain syndromes. Reported evidence to date has come from only small observational studies. We present the first community-based study to show an association between nonsyndromal CKD and hearing loss.

STUDY DESIGN: Cross-sectional population-based study to examine the relationship between CKD and age-related hearing loss.

SETTING & PARTICIPANTS: The Blue Mountains Hearing Study is a survey of age-related hearing loss conducted in 1997-2004; a total of 2,564 participants had audiometric testing and complete renal data.

PREDICTOR OR FACTOR: Moderate CKD, defined as estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m(2).

OUTCOMES: Bilateral hearing loss, defined as average pure-tone threshold >25 dB for measurements at frequencies of 0.5, 1.0, 2.0, and 4.0 kHz.

MEASUREMENTS: Baseline biochemistry tests, including serum creatinine, were performed. Pure-tone audiometry was performed in sound-treated booths.

RESULTS: Moderate CKD was present in 513 of 2,564 participants. Of persons with moderate CKD, 279 (54.4%) had measured hearing loss compared with 581 (28.3%) with eGFR ≥60 mL/min/1.73 m(2). Moderate CKD was independently associated with hearing loss (OR, 1.43; 95% CI, 1.10-1.84; P = 0.006) after adjusting for age; sex; noise exposure; education; diabetes, hypertension, and stroke histories; and smoking. Participants with eGFR <45 mL/min/1.73 m(2) had the highest prevalence of hearing loss (73%) compared with those with eGFR ≥90 mL/min/1.73 m(2) (19%; multivariate adjusted OR, 2.4 [95% CI, 1.3-4.5]). Analyses were repeated after excluding participants reporting furosemide use (a known ototoxic agent); the association between moderate CKD and hearing loss remained significant (multivariate adjusted OR, 1.40 [95% CI, 1.08-1.83]; P = 0.01).

LIMITATIONS: The present study is not longitudinal and does not permit causal inference from the observed associations.

CONCLUSIONS: Moderate CKD per se was associated independently with hearing loss. Recognizing this link could lead to earlier hearing assessment with appropriate interventions to preserve the hearing of patients with CKD.