| Recommendations |
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| Relative values of different outcomes | The following outcomes were identified as critical outcomes for this review: hearing-specific health-related quality of life (key domain: participation) and the specific adverse event of pain. Important outcomes included health-related quality of life, listening ability and the specific adverse event of noise-induced hearing loss. |
| Quality of the clinical evidence | The quality of the evidence was moderate for hearing-specific health-related quality of life and for health related quality of life and very low for the outcomes relating to adverse events (pain and noise induced hearing loss). All of the outcomes were downgraded for a high risk of bias. This was mainly due to a high risk of selection, performance or detection biases. These biases are widely acknowledged to be problematic within hearing aid intervention studies as the blinding of patients and outcome assessors can be difficult to achieve. 30,31 One of the studies had a follow-up period of 6 weeks but the committee agreed that the evidence should not be downgraded for indirectness as there is unlikely to be a significant clinical difference between a 6 week follow-up and an 8 week follow-up as specified in the protocol. For the outcome of hearing-specific health-related quality of life where participation is the key domain, moderate quality evidence showed that hearing aids had a large beneficial effect in reducing participation restrictions. There were significant differences in the size of effects across studies. The effects reported by 2 studies in Veterans’ Administration settings were similar but more than twice the size of the effect reported by the third study which was set in a university hospital clinic. However, all 3 studies individually reported large beneficial effects that favoured hearing aids, meaning that while further evidence may change the size of the overall effect on hearing-specific health-related quality of life, there is high confidence in the magnitude and direction of the effect. For the outcome of health-related quality of life as measured by the WHO Disability Assessment Schedule II (WHO-DAS II) scale 1 study showed a significant benefit of hearing aids compared with placebo or no hearing aids. Using the Self-evaluation of Life Function, another study found no significant beneficial effect of hearing aids. Overall, moderate quality evidence showed a small overall beneficial effect of hearing aids. For listening ability, moderate quality evidence showed a large beneficial effect of hearing aids compared with unaided/placebo conditions based on 1 study that used the APHAB and another study that used the PHAP. The planned subgroup analyses (age, sex, and degree of hearing loss) could not be performed as data from these subgroups were not reported. No evidence was found comparing hearing aids to an active control (information or education only, listening tactics and communication training; assistive listening devices; or auditory training) or for the outcomes of pain or noise-induced hearing loss. |
| Trade-off between clinical benefits and harms | The committee noted the limitations of the studies but agreed that the evidence demonstrated that people with mild to moderate hearing loss benefitted from having hearing aids as this improved their listening ability and quality of life. The committee acknowledged the difference hearing aids can make by enabling people to participate in everyday situations and the impact this can have in improving the quality of life for people with hearing difficulties. The committee agreed that having hearing aids at an early stage of their hearing loss enables people to adjust more easily to using the aids. The committee is aware that people are often reluctant to seek help or are slow at identifying a difficulty. There is evidence that people have not been referred for further assessment when hearing loss is first suspected (see also chapter 8 on early versus delayed management of hearing loss).28 The committee noted that reporting for mild and moderate hearing loss had not been clearly separated in the studies. |
| Trade-off between net clinical effects and costs | One published economic evaluation was identified for this question. This measured the benefit to quality of life in 78 patients given hearing aid(s) for the first time and used this benefit in a lifetime model of hearing aid use. It found that hearing aid use was cost effective compared with no hearing aids at a cost-effectiveness threshold of £20,000 per QALY gained (ICER: £11,555 per QALY gained). However, the committee noted that the costs used in the study differed from current UK costs: in particular the cost used for hearing aids was much higher than UK costs. It also assumed a much longer time between replacement of hearing aids (at least 8 years), and a lower rate of fitting of 2 hearing aids (only 25%) than currently expected in the UK. Consequently the results of this analysis cannot be relied upon to relate to the current UK context. The committee therefore also considered the relevance of the original economic modelling conducted for the early versus delayed management question in this guideline. By comparing both of the intervention arms (‘early’ and ‘delayed’) against the no treatment arm, the benefit of referring for assessment and, where suitable, prescribing and fitting hearing aids is demonstrated. This analysis showed that either early or delayed fitting of hearing aids would be highly cost effective compared with no treatment at the NICE cost-effectiveness threshold of £20,000 per QALY gained, with ICERs of £4,167 per QALY and £4,421 per QALY respectively. The original modelling was not able to look into the effect of using different hearing loss thresholds, as there is no comparative evidence on the benefit to quality of life of improving hearing for people with different levels of hearing loss. However, sensitivity analysis which dramatically reduced the benefits of hearing aids for the whole population, and sensitivity analysis that increased the proportion of people either not suitable for hearing aids or dropping out after being fitted with hearing aids indicate that even if those people with lower levels of hearing loss benefit by a smaller amount than the average benefit expected in the model, the intervention would still be very cost effective overall. In addition, the committee noted that there is no standard universal definition of hearing loss. While the BSA criteria fit best with current understanding and practice in the UK, in the Cochrane review the international WHO classification was used. The committee agreed that decision-making on whether to fit hearing aids should not be based on a threshold measurement alone but on a combination of hearing measurement and communication difficulties. The committee therefore agreed that audiologists should be able to use their expertise to assess whether a person would benefit clinically from using hearing aid(s) due to their hearing loss, and if so they should offer hearing aid(s) and discuss this with the person. The committee agreed that provision of hearing aids to all who would benefit from them will be cost effective at a cost-effectiveness threshold of £20,000 per QALY gained. |
| Other considerations | The committee acknowledged that there is variation across the UK in whether people with mild to moderate hearing losses receive hearing aid(s) and consider that the decision to fit should be based on need rather than on hearing thresholds. Furthermore, as amplification has been shown to have benefit and is cost effective, hearing aids should be offered at the first opportunity if the individual is likely to benefit. The committee expressed concern that not providing hearing aids, and the care needed to use them effectively, to a person with an aidable hearing loss, raises serious questions of inequality of access. Hearing aids can make a difference to the ability of a person with hearing loss to communicate effectively and can thus reduce the impact of their impairment. Their impairment is permanent and even a mild hearing loss can have a significant effect on day-to-day functioning. The NHS England commissioning framework for adult hearing loss provides guidance on how high quality audiology services and pathways can be designed.86 |
From: 15, Hearing aids
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