Economic Evaluation and Research Prioritization of Adult Hearing Screening in the United States

AbstractHearing loss affects over 500 million people globally, is the fourth leading cause of years lived with disability worldwide, and carries an economic burden of over $700 billion annually.1-3 In the United States (US), one in three persons over the age of 60 have hearing loss, yet only 20% of those with hearing loss utilize a hearing aid.4,5 This treatment gap leaves 80% of hearing-impaired older adults without treatment that has proven effectiveness in enhancing quality of life, reducing loneliness, and potentially improving physical and cognitive health.6,7 While early hearing aid provision and use is associated with better long-term hearing outcomes, patients may wait on average 10-15 years before seeking treatment for hearing loss due to several factors including psychosocial factors, cost, and lack of awareness of their hearing loss.8,9 Adult hearing screening programs have the potential to address the failure in detection and diagnosis that contributes to the majority of patients with hearing loss not receiving effective treatment. One randomized trial of a hearing screening program in US veterans found increased uptake of hearing aids in screened patients.10 However, current US clinical guidelines on adult hearing screening are conflicting, with some recommending frequent screening and others giving no guidance due to sparse data.11 While international stakeholders have increasingly called for investment to alleviate the impact of hearing loss, US policymakers do not currently have sufficient quantitative evidence around long-term clinical and economic effects of adult hearing screening programs.12-14 Further, both the NIDCD and National Academy of Medicine have called for research identifying cost-effective strategies for hearing loss diagnosis and treatment. Decision analysis is one quantitative method that can synthesize existing evidence to clarify long-term dynamics and trade-offs inherent in hearing health policy decisions. Indeed, decision models have had wide-reaching policy implications in the hearing health care space.15 Decision analysis can also identify optimal areas for future research investment through value of information (VOI) analysis. However, there is a dearth of evidence regarding long-term impacts of adult hearing screening policies: a recent systematic review identified no decision models that evaluate adult hearing screening programs in the US.16 This dissertation addresses this evidence gap via three specific aims with the long-term goal of helping policymakers identify the most effective and cost-effective adult hearing screening strategies for their populations.

Aim 1: To develop and validate a decision modeling framework of adult hearing screening, diagnosis, and treatment.We collaborated with the Lancet Commission on Hearing Loss to outline model structure, identify input data sources, and calibrate/validate DeciBHAL-US (Decision model of the Burden of Hearing loss Across the Lifespan). We populated the model with literature-based estimates and validated the conceptual model with key informants. We validated key model endpoints to the published literature, including: 1) natural history of sensorineural hearing loss (SNHL), 2) natural history of conductive hearing loss (CHL), and 3) the hearing loss cascade of care. We reported the coefficient of variance root mean square error (CV-RMSE), considering values ≤15% to indicate adequate fit. For SNHL prevalence, the CV-RMSE for model projected male and female age-specific prevalence compared to sex-adjusted National Health and Nutrition Examination Survey (NHANES) data was 4.9 and 5.7%, respectively. Incorporating literature-based age-related decline in SNHL, we validated mean four-frequency average hearing loss in the better ear (dB) among all persons to longitudinal data (CV-RMSE=11.3%). We validated the age-stratified prevalence of CHL to adjusted NHANES data (CV-RMSE=10.9%). We incorporated age- and severity-stratified time to first hearing aid (HA) use data and HA discontinuation data (adjusted for time-period of use) and validated to NHANES estimates on the prevalence of adult HA use (CV-RMSE=10.3%). Our results indicate adequate model fit to internal and external validation data. Future incorporation of cost and severity-stratified utility data will allow for cost-effectiveness analysis of US hearing healthcare interventions across the lifespan. Further research might expand the modeling framework to international settings.

Aim 2: To project clinical and economic effects of adult hearing screening programs in the US.We sought to estimate long-term clinical and economic effects of alternative adult hearing screening schedules in the US. Our design was a model-based cost-effectiveness analysis simulating current detection and linkage of persons with HL to hearing healthcare (Current Detection; CD) compared to alternative screening schedules varying by age at first screen (45 to 75 years) and screening frequency (every 1 or 5 years). Simulated persons experience yearly age- and sex-specific probabilities of acquiring HL, and subsequent hearing aid uptake (0.5-8%/year) and discontinuation (13-4%). Quality-adjusted life-years (QALYs) were estimated according to hearing level and treatment status. Costs include screening ($30-120; 2020 USD), HL diagnosis ($300), and hearing aid devices ($3,690 year 1, $910/subsequent year). The intervention was alternative screening schedules that increase baseline probabilities of hearing aid uptake (base-case 1.62-fold; range 1.05-2.25-fold). We found that CD resulted in 1.20 average person-years of hearing aid use compared to 1.27-1.68 with the screening schedules. Lifetime total per-person undiscounted costs were $3,300 for CD and ranged from $3,630 for 5-yearly screening beginning at age 75 to $6,490 for yearly screening beginning at age 45. In cost-effectiveness analysis, yearly screening beginning at ages 75, 65, and 55 years had ICERs of $39,100/QALY, $48,900/QALY, and $96,900/QALY, respectively. Results were most sensitive to variations in hearing aid utility benefit and screening effectiveness. We conclude that yearly hearing screening beginning at age 55 is cost-effective by US standards.

Aim 3: To inform future research prioritization through value of information analysis.We sought to project the monetary value of future research clarifying uncertainties around the optimal adult hearing screening schedule. We used a validated decision model of hearing loss natural history, diagnosis, and treatment (DeciBHAL-US) to simulate current detection and linkage of hearing loss versus several hearing screening schedules. Key model inputs included hearing loss incidence (0.06-10.42%/year), hearing aid uptake (0.54-8.14%/year), screening effectiveness (1.62x hearing aid uptake), utility benefits of hearing aids (+0.11), and costs of hearing aid devices ($3,690). We assigned distributions to uncertain model parameters to conduct probabilistic uncertainty analysis (PUA). We used value of information analysis to estimate the expected value of perfect information (EVPI), and expected value of partial perfect information (EVPPI), using a willingness-to-pay (WTP) of $100,000/quality-adjusted life-year (QALY). EVPI and EVPPI estimate the upper bound of the dollar value of a future research project. The intervention was screening schedules beginning at ages 45, 55, 65, and 75 years, and frequencies of every 1 or 5 years. The PUA demonstrated high uncertainty around the optimal screening schedule. Yearly screening beginning at age 55 was the optimal screening schedule in 38% of simulations, and other schedules in 62%. The population EVPI, or value of reducing all decision uncertainty, was $8.2-12.6 billion varying with WTP and the EVPPI, or value of reducing all screening effectiveness uncertainty, was $2.6 billion. We conclude that there is large uncertainty around the optimal adult hearing screening schedule and future research is likely justified.