National Institutes of Health Funding for Hearing Loss Research

Abstract

This analysis of 2017 National Institutes of Health funding data examines the relative funding for hearing loss research compared with 29 other conditions.

The National Institutes of Health (NIH) is the largest public funder of health research in the United States. According to its organization-wide strategic plan, a key priority is supporting research into conditions with the greatest disease burden.¹ Since 2009, the NIH has informed the public about allocation of funds for over 280 selected conditions through its annual Research, Condition, and Disease Categorization (RCDC) process. Reports are generated by text analysis of funded grants and contracts, searching for keywords related to the selected conditions.²

Hearing loss is not one of the RCDC-selected conditions, nor is it subsumed under any of the other conditions. For this study, auxiliary NIH data sources were used to quantify funding for hearing loss research and analyze funding relative to disease burden.

Methods

Measures of NIH Spending on Research

Actual NIH funding for research on RCDC conditions in fiscal year (FY) 2017 was downloaded from the NIH website,³ and NIH funding for research for hearing loss in FY 2017 was ascertained by searching the NIH RePORTER database for projects (grants and contracts, intramural and extramural) funded in FY 2017 by any of the NIH institutes and centers, searching titles and abstracts for “hearing loss,” “hearing impairment,” and “deafness.” Projects with any of these terms in either the title or the abstract were extracted.

Measures of Disease Burden in the United States in 2015

Disability-adjusted life-years (DALYs), years lived with disability, and deaths are measures of disease burden that have been consistently used in prior analyses of disease burden relative to NIH funding.^4,5 Estimates for these 3 measures in the United States in 2015 were downloaded from the Global Burden of Disease network’s website.⁶

Analysis

Statistics for NIH funding and disease burden were tallied. To explore the association between disease burden and funding, an approach that has been taken by previous researchers was adopted,^4,5 focusing on 29 common conditions for which there are straightforward correspondences between RCDC categories and Global Burden of Disease project categories. Funding and disease burden were log-transformed in regression analysis to normalize skewed distributions.^4,5 For this study, Stata SE, version15.0 (StataCorp LLC), was used for statistical analysis, and P < .05 (2-sided) indicated significance. This study was deemed exempt from institutional review board approval because it is not human subjects research.

Findings

The FY 2017 NIH funding for hearing loss research totaled $202 million dollars. Hearing loss ranked 20th in NIH funding, 10th for DALYs, and 5th for years lived with disability when considered along with the 29 common conditions that have been used in prior studies (Table). Because hearing loss is not a cause of death, it was not ranked on that measure of disease burden.

Table. NIH Research Funding and Disease Burden for 30 Common Conditions or Diseases in the United States.

Condition or Disease	2017 NIH Research Funds, $ Millionsa	2015 DALYs, Millions (Rank)	2015 YLDs, Millions (Rank)	2015 Deaths, Thousands (Rank)
HIV/AIDS	3000	0.39 (22)	0.12 (17)	7.0 (18)
Alzheimer disease	1423	2.46 (7)	0.41 (12)	249.9 (2)
Diabetes	1108	3.73 (4)	2.51 (2)	63.5 (8)
Breast cancer	689	1.19 (14)	0.17 (16)	46.5 (10)
Perinatal/neonatal conditions	616	1.89 (9)	0.84 (8)	12.0 (15)
Dental/oral disorders	541	0.86 (16)	0.86 (7)	NAb
Alcohol	500	1.07 (15)	0.60 (11)	13.3 (14)
Injuries	496	9.64 (1)	3.28 (1)	179.1 (3)
Ischemic heart disease	444	7.63 (2)	0.23 (14)	506.6 (1)
Depression	438	1.94 (8)	1.94 (4)	NAb
Lung cancer	352	3.51 (5)	0.06 (22)	178.2 (4)
Tuberculosis	347	0.02 (30)	0.00 (30)	0.9 (23)
Stroke	331	3.36 (6)	1.13 (6)	163.8 (5)
Sexually transmitted diseases	322	0.06 (28)	0.06 (23)	0.2 (24)
Asthma	286	0.73 (17)	0.62 (10)	3.8 (21)
Cirrhosis	285	1.70 (11)	0.08 (20)	61.1 (9)
Colon cancer	270	1.51 (12)	0.10 (18)	74.4 (7)
Schizophrenia	243	0.71 (18)	0.71 (9)	NAb
Prostate cancer	239	0.63 (19)	0.18 (15)	33.2 (11)
Hearing loss	202	1.75 (10)	1.75 (5)	NAb
Parkinson disease	168	0.39 (21)	0.07 (21)	28.4 (12)
Epilepsy	154	0.40 (20)	0.32 (13)	2.2 (22)
Ovarian cancer	151	0.34 (23)	0.01 (28)	15.6 (13)
Cervical cancer	114	0.20 (24)	0.01 (29)	7.2 (17)
Pneumonia	114	1.35 (13)	0.02 (27)	0.1 (25)
Multiple sclerosis	111	0.20 (25)	0.10 (19)	3.8 (20)
Chronic obstructive pulmonary disease	100	4.53 (3)	2.10 (3)	163.0 (6)
Uterine cancer	45	0.19 (26)	0.04 (26)	7.9 (16)
Otitis media	9	0.05 (29)	0.05 (24)	0.1 (26)
Peptic ulcer disease	8	0.13 (27)	0.04 (25)	5.4 (19)

Abbreviations: DALYs, disability-adjusted life-years; NA, not applicable; NIH, National Institutes of Health; YLDs, years lived with disability.

^aResearch funds are actual NIH funding for fiscal year 2017.³

^bCondition or disease is not deemed a cause of death by the Global Burden of Disease project and is not ranked for death.

Of the 3 burden measures, DALYs was the most strongly correlated with funding (r² = 0.23; P = .008). Deaths (r² = 0.22; P = .02) and years lived with disability (r² = 0.14; P = .04) were not as strongly correlated with funding. The Figure shows a scatterplot of DALYs vs funding, with a superimposed linear fit line. Compared with research on many of the other common conditions and diseases, hearing loss research appears to be relatively underfunded relative to disease burden measured in DALYs.

Figure. Disability-Adjusted Life-Years (DALYs) and National Institutes of Health (NIH) Research Funding for 30 Common Conditions and Diseases.

To explore the association between disease burden and funding for 30 conditions, information on DALYs for 2015 was downloaded from the Global Burden of Disease website. Information on 2017 NIH spending on research on 29 of the conditions was extracted from the NIH Research, Condition, and Disease database, and information on NIH spending on research on hearing loss was extracted from the NIH RePORTER. Funding and disease burden were log transformed in regression analysis to normalize skewed distributions. The shaded area indicates the 95% CI for the regression of log (DALYs) on log (NIH research spending).

Discussion

The NIH is committed to improved transparency about the allocation of public funds.¹ The annual RCDC reports have great potential for monitoring trends. However, the reports will be most effective if they align with the NIH’s intention (expressed in its current Strategic Plan) to make disease burden a “crucial consideration” in prioritizing funding.¹

To be sure, funding diseases with the highest burden is only one of the NIH goals, and disease burden is a complex, multidimensional notion. Hearing loss is emblematic of that complexity because it causes great burden in terms of disability but is not a cause of death. In these analyses, funding for hearing loss was compared with funding for key RCDC conditions. Level of hearing loss funding was determined using a different method than that used for the other conditions. This was unavoidable because the RCDC method is customized for each condition, with definitions, weights, and thresholds developed by expert consensus. The method has not yet been used to quantify funding for hearing loss research.

Hearing loss has been called the “hidden disability” and is often overlooked by policy makers, clinicians, and the public. Funding from the NIH reflects our national investment in solving health problems. Funding should be tracked for hearing loss, a major contributor to disease burden and lost health in the United States.