Expert Roundtable | September 2015 Hearing Review

Note: This is the fourth article in a seven-part special Expert Roundtable series published in the September 2015 edition of The Hearing Review, guest-edited by Douglas Beck, AuD. For all the articles in this Expert Roundtable, click here.

Chapter 4: Strategies for addressing unique patient needs

Because factors like cognition, health literacy, vision, and hearing aid handling ability influence hearing aid outcomes, professionals have a responsibility to address these issues during hearing aid instruction and counseling.

Non-auditory factors such as cognition, memory/recall, manual dexterity, tactile sensitivity, health literacy, and vision influence hearing aid outcomes. Research shows these factors are not independent. Specifically, cognitive decline, age-related vision loss,1 poor motor skills,2 and decreased health literacy3 are often associated with each other. This suggests that older patients with diminished cognitive ability are likely to demonstrate other deficits like those above.

Gabrielle Saunders, PhD

Gabrielle Saunders, PhD

Data from an ongoing study in our laboratory illustrates these intertwined relationships and, more importantly, their association with hearing aid outcome. In this study, we are characterizing participants before they receive their first pair of hearing aids using a variety of non-auditory test measures, and then assessing hearing aid outcome 4 to 8 weeks after the hearing aid fitting. Outcome is measured with the International Outcome Inventory for Hearing Aids (IOI-HA)4 and the Hearing Aid Skills and Knowledge (HASK) test. The IOI-HA is a 7-item self-report measure on which seven dimensions of outcome are rated (Use, Benefit, Residual Activity Limitations, Satisfaction, Residual Participation Restrictions, Impact on Others, and Quality of Life). Higher scores on the IOI-HA indicate better outcome. The HASK was developed specifically for this study to measure both knowledge and skills for hearing aid management. Individuals answer questions about hearing aid management (Knowledge) and then demonstrate the activity (Skill) to the tester. The HASK is scored as a percentage correct for Knowledge and Skill separately.

To date, data are available from 103 veteran participants with mild-to-moderate sensorineural hearing loss, aged between 50 and 86 years. Scores on the non-auditory measures show the sample to be heterogeneous in their performance. Specifically, cognitive function measured using four subtests from the Rivermead Behavioral Memory Test (RMBT)5 shows that only one third (34%) of participants performed within age-based norms on all four subtests, with 33% performing below age-based norms on one subtest, 25% on two subtests, and 8% on three or four subtests. The subtests we used assess skills required for hearing aid management—the ability to learn and recall how to conduct a new task (Novel Task Immediate and Delayed subtests), the ability to recognize visual materials (Picture Recognition subtest), and the ability to recall spontaneously when to do a required action (Belongings subtest). A similar pattern was seen for performance on the Discourse Comprehension Test (DCT)6 on which a third of participants (37%) performed below clinical norms. The DCT measures the ability to comprehend, draw inferences from and recall the content of short stories.

As applied to hearing aids, our preliminary results suggest that over a third of the population could have considerable difficulty understanding and applying information provided during hearing aid instruction. In addition, a third of participants (36%) had poor manual dexterity (performed >1SD below mean of norms) as measured by the Grooved Pegboard test,7 74% had poor sensitivity in their dominant hand index finger and/or thumb as measured by the JVP Domes test,8 and 82% scored outside of age-based norms on a test of visual contrast sensitivity (Smith-Kettlewell Institute Low Luminance or SKILL card).9 On a positive note, 94% of participants had adequate health literacy as measured with the Short Test of Functional Health Literacy in Adults (S-TOFHLA).10 Together these findings suggest that, among a typical population of older first-time hearing aid users, there will be many individuals who encounter difficulties handling and learning to manage their new hearing aids.

Our outcome data show this concern is more than hypothetical. Stepwise, multiple linear regression showed that hearing aid outcome is highly related to hearing aid handling ability and to health literacy, in that the HASK Skill score explained 30% of the variance in IOI-HA total score, with S-TOFHLA scores explaining a further 9% of the variance. Scores on the Novel Task and Picture Recognition subtests of the RMBT, and performance on the DCT, SKILL, and JVP Domes tests were also significantly correlated with IOI-HA scores, and HASK Skills scores were significantly correlated with manual dexterity. In sum, it is clear that cognition and other non-auditory factors impact hearing aid outcome.

What do these findings mean for hearing care professionals and clinical practice? Audiologists and dispensing professionals have a responsibility to address these issues during hearing aid instruction and counseling. This can be achieved in several simple ways. Here are some suggestions: 1) Provide take-home materials to assist patients with memory issues; 2) Ensure all information shared is in accordance with “health literacy universal precautions”11 which benefit all patients, especially those with poorer health literacy; 3) Always emphasize the need for good lighting when cleaning and maintaining hearing aids to help the many patients with diminished contrast sensitivity; 4) Counsel patients about the need to be patient when handling their hearing aids, especially those with poor manual dexterity and tactile sensitivity, and 5) Involve a spouse, family member, or caregiver during hearing aid instruction and orientation. This will provide additional support for the patient, regardless of their basic abilities.

An excellent resource that addresses many of these issues is the AHRQ Health Literacy Universal Precautions Toolkit.11 It provides evidence-based guidance for medical professionals on spoken communication, written communication, self-management, and empowerment and supportive systems.

Acknowledgements

The author thanks M. Samantha Lewis, Jay Vachhani, Sara Sell, Katharina Echt, and Susan Griest for their vital work and contributions in this paper.

References

  1. Rozzini L, Riva M, Ghilardi N, Facchinetti P, Forbice E, Semeraro F, Padovani A. Cognitive dysfunction and age-related macular degeneration. Am J Alzheimers Dis Other Demen. 2014;29:256-262.

  2. Kluger A, Gianutsos JG, Golomb J, Ferris SH, George AE, Franssen E, Reisberg B. Patterns of motor impairment in normal aging, mild cognitive decline, and early Alzheimer’s disease. J Gerontol B Psychol Sci Soc Sci. 1997;52:28-39.

  3. Kobayashi LC, Wardle J, Wolf MS, von Wagner C. Cognitive function and health literacy decline in a cohort of aging English adults. J Gen Intern Med. 2015 Jul;30(7):958-64. doi: 10.1007/s11606-015-3206-9

  4. Cox RM, Alexander GC, Beyer CM. Norms for the international outcome inventory for hearing aids. J Am Acad Audiol. 2003;14(8):403-13.

  5. Wilson BA, Greenfield E, Clare L, Baddeley AD, Cockburn J, Watson P, Tate R, Sopena S, Nannery R, Crawford J. Rivermead Behavioural Memory Test – Third Edition (RBMT-3). London: Pearson Education Ltd;2008.

  6. Brookshire RH, Nicholas LE. The Discourse Comprehension Test. 2nd Ed. Albuquerque, NM;1997.

  7. Matthews CG, Klove H. Instruction Manual for the Adult Neuropsychology Test Battery. Madison, Wis: University of Wisconsin Medical School;1964.

  8. Stoelting Co. J.V.P. Domes for Cutaneous Spatial Resolution Measurement. Operations Manual. Woodale, Ill:Stoelting Co;1997.

  9. Haegerstrom-Portnoy G, Brabyn J, Schneck M, et al. The SKILL Card. An acuity test of reduced luminance and contrast. Smith-Kettlewell Institute Low Luminance. Invest Ophthalmol Vis Sci. 1997;38:207-18.

  10. Baker DW, Gazmararian JA, Sudano J, Patterson M. The association between age and health literacy among elderly persons. J Gerontol B Psychol Sci Soc Sci. 2000;55(6)[Nov]:S368-74.

  11. Brega AG, Barnard J, Mabachi NM, Weiss BD, DeWalt DA, Brach C, Cifuentes M, Albright K, West, DR. AHRQ Health Literacy Universal Precautions Toolkit, 2nd Ed. (Prepared by Colorado Health Outcomes Program, University of Colorado Anschutz Medical Campus under Contract No. HHSA290200710008, TO#10.) AHRQ Publication No. 15-0023-EF) Rockville, MD. Agency for Healthcare Research and Quality. January 2015. Available at: http://www.ahrq.gov/professionals/quality-patient-safety/quality-resources/tools/literacy-toolkit

Gabrielle Saunders, PhD, is associate director of the National Center for Rehabilitative Auditory Research (NCRAR), a division of the US Dept of Veterans Affairs, and associate professor in the department of otolaryngology at Oregon Health and Science University.

Correspondence can be addressed to HR or Dr Saunders at [email protected]

Original citation for this article: Saunders G. Hearing aid outcomes and the influence of non-auditory factors. Hearing Review. 2015;22(9):19.

This article is one of seven chapters in a series of articles that review the key points addressed during the 2015 AudiologyNOW! session titled “Issues, Advances, and Considerations in Cognition and Amplification.” Follow the links to related chapters by Douglas L. Beck, PhD, Brent Edwards PhD, Christian Füllgrabe, PhD, Jason Galster, PhD, Andrea Pittman, PhD, and Gurjit Singh, PhD.