The purpose was to assess differences in outpatient ophthalmologic usage based on patient characteristics such as race/ethnicity, income, insurance type, geographical region, and educational attainment.
Retrospective cross-sectional study.
The Medical Expenditure Panel Survey (MEPS) is a nationally representative data set for the noninstitutionalized population cosponsored by the Agency for Healthcare Research. This study involved 183,054 MEPS respondents from 2007 to 2015. Primary outcome measure was patient utilization of outpatient ophthalmologic care. Secondary outcome measure was annual health care use and costs by patients in outpatient, inpatient, and the emergency department settings based on race.
Overall, 21,673 participants self-reported an ophthalmologic condition, and 12,462 had at least 1 outpatient ophthalmologic visit. Hispanic (adjusted odds ratio [aOR] 0.72; P < .001) and black patients (aOR 0.74; P < .001) had fewer outpatient visits than their non-Hispanic white counterparts. Uninsured (aOR 0.41; P = .009) and Medicare/Medicaid (aOR 0.92; P < .001) patients had less outpatient care than their privately insured counterparts. Increasing income and education was associated with higher outpatient ophthalmologic care utilization. In the emergency department, non-Hispanic white patients had the least encounters (1.1 per 100 patients) and highest costs ($25,314.05) when compared to non-Hispanic black patients (3.2 encounters per 100 patients and $10,780.22 respectively) and Hispanic patients (2.2 encounters per 100 patients and $9,837.03 respectively).
This study’s findings demonstrate differences in outpatient ophthalmologic utilization based on demographic and socioeconomic characteristics. Concurrently, minority Americans had more ophthalmic emergency department visits but lower cost per visit. There is a need to further characterize these differences to predict future ophthalmologic care needs.
Demographically disadvantaged Americans had fewer outpatient ophthalmologist visits.
Geographically, Americans in the Midwest and West had less outpatient utilization.
Minority Americans had more ophthalmic emergency department visits but lower cost per visit.
Current models may not be sufficient for expected population demographic changes.
Further characterization of these results is needed to better predict future needs.
Ophthalmologic illness is common, affecting 2.9% of all Americans. Blindness or low vision affects approximately 1 in 28 Americans older than 40 years. The most common causes of severe vision loss in older adults include age-related macular degeneration (AMD), ocular complications of diabetes mellitus, glaucoma, and cataracts. These diseases can have serious, detrimental effects on the quality of life of those affected and can lead to more falls, increased social isolation, and performance of daily activities. Approximately 8.6% of Americans aged 18 years and older have been diagnosed with cataracts, 2.0% have been diagnosed with glaucoma, and 1.1% have been diagnosed with macular degeneration. In addition to the primary ophthalmologic diseases, diabetic retinopathy can result as a sequelae of diabetes mellitus and can pose serious ophthalmologic problems. The number of people with visual impairment disorders has been projected to increase 71% from 2010 to 2030, and 210% from 2010 to 2050. Better methods of detection, longer life spans, and an aging population all contribute to the increasing prevalence of ophthalmologic diseases.
Discrepancies have been observed in access to health care and prevalence of ophthalmologic conditions based on demographic characteristics. For patients with a self-reported visual impairment, patients with less than a high school education and income below the poverty threshold are less likely to have visited an ophthalmologist every year. Additionally, the prevalence of the primary ophthalmologic diseases differ along racial/ethnic subgroups. The importance of access to health care among the underprivileged is underscored by the fact that the prevalence of diabetic retinopathy is higher among those with less than high school education, lower income levels, and non-Hispanic blacks. Additionally, the prevalence of glaucoma is higher among non-Hispanic blacks than among non-Hispanic whites whereas the prevalence is higher among non-Hispanic whites for AMD and cataract surgery. The prevalence of AMD is also higher among those with lower income levels.
The prevalence of these conditions are all expected to rise in the coming years. Current projections may be inadequate for generating reliable prediction model due to the expected changes in the demographics of the populations expected in the future. As such, there is a need to better categorize socioeconomic and demographic differences in the utilization of ophthalmologic care. The goal of this study was to assess differences in outpatient ophthalmologic usage based on patient demographic characteristics.
The Medical Expenditure Panel Survey (MEPS) is a set of large-scale surveys of families and individuals, their medical providers, and employers across the United States and was used for this retrospective study. The MEPS survey is cosponsored by the Agency for Healthcare Research and Quality (AHRQ) and the National Center for Health Statistics (NCHS). It is a nationally representative survey of the noninstitutionalized American civilian population based on a subsample of households that participate in the National Health Interview Survey (conducted by the National Center for Health Statistics) and collects patient data such as medical expenses, demographic characteristics, health conditions, and access to care using questionnaires fielded to individual household members and their medical providers. More details about the MEPS designs and methods are available elsewhere. Institutional review board approval was not needed to use this deidentified and publicly available database, and waiver of approval was obtained for this study. Data collection was in conformity with all federal and state laws, informed consent was obtained, and was in adherence to the tenets of the Declaration of Helsinki. This study is a retrospective analysis of 9 years of data from the MEPS database (2007-2015), which was used to assess patterns of use of outpatient ophthalmologic care in the United States.
To analyze outpatient ophthalmic use and expenditures with demographic characteristics and medical diagnoses, the household component of the MEPS database, event files, and medical conditions were linked. Patients were determined to have an ophthalmic condition based on its International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) code. MEPS clinical classification codes (which correlate with ICD-9-CM codes that can be found on the MEPS website) that were considered ophthalmic conditions included cataracts, glaucoma, blindness and vision defects, inflammatory condition of the eye, retinal detachments, retinal vascular occlusions, retinopathies, and other conditions of the eye.
Study Variables and Statistical Analysis
For each patient, total outpatient ophthalmology visits and expenditures, which included all payments by third-party payers and out-of-pocket costs, were recorded. Using total outpatient ophthalmic visits for these individuals, the percentage of individuals with an ophthalmologic condition with 1 or more visits to an outpatient ophthalmology site from 2007 to 2015 was reported. All expenditures were adjusted to 2015 US dollars using the urban Consumer Price Index of the US Bureau of Labor Statistics. With these data, we investigated the per capita expenditures and visit rates for ophthalmologic visits based on certain demographic characteristics. Self-identified race/ethnicity were categorized as non-Hispanic white, Hispanic, or black. Other racial/ethnic groups were not included because of the wide 95% confidence intervals (CIs) produced by MEPS for those groups. Age was categorized as younger than 18, 18-34, 35-64, or 65 years and older. Educational level was categorized as no degree, a high school diploma or equivalent, some college, or a bachelor’s degree or higher. Income was calculated in relation to the 2015 federal poverty level (FPL). Individuals were categorized as poor (<100% of FPL), near poor (100%-124% of FPL), low income (125%-199% of FPL), middle income (200%-399% of FPL), or high income (>399% of FPL). Insurance status was categorized as private (includes patients with concurrent Medicare coverage), public (Medicare or Medicaid patients with no private insurance), or uninsured. For regional analysis, patients were categorized as living in the Northeast, South, Midwest, or West. The states that were incorporated into each region as defined by the US Census Bureau can be seen in Supplemental Table 1 . Patient self-reported health status was coded on a 5-point scale ranging from poor, fair, good, very good, or excellent.
A multivariable logistic regression model was used to determine the association of the various demographic and socioeconomic characteristics with utilization of outpatient ophthalmologic care during the time frame (2007-2015) as the outcome variable. These characteristics include age, sex, race/ethnicity, geographic region, income levels, educational attainment, insurance type, self-reported condition, and self-reported health status. An alpha level of 0.05 was used to determine statistical significance. Adjusted odds ratios (aORs) and 95% CIs were calculated for each variable to generate multivariable logistic regression models. Lastly, the percentage of patients having at least 1 visit to an outpatient ophthalmic center was stratified based on their race/ethnicity (Hispanic, non-Hispanic white, and black) and the cost per person with an ophthalmic condition for outpatient visits were used to analyze differences in health care expenditures. The referent categories were 65 years and older (age), female (sex), non-Hispanic white (race/ethnicity), Northeast (geographic region), high income (income), bachelor’s degree or higher (educational attainment), privately insured (insurance status), no self-reported condition, and excellent self-reported health status. All of the tables in this study summarize annual averages from 2007 to 2015, which were derived using person-level weights provided by the AHRQ, and was extrapolated to the civilian noninstitutionalized US population. All analyses were performed at the person level using statistical software (R; R Foundation for Statistical Computing, Vienna, Austria).
In total, our sample included 183,054 MEPS respondents from 2007 to 2015 ( Table 1 ). The mean (SD) age of the population was 34 (23) years, and 52.1% of the participants were female. Of these participants, 21,673 (11.84%) self-reported an ophthalmologic condition.
|Demographic Group of Patients With an Ophthalmologic Condition||Percentage With ≥1 Ophthalmologist Visit From 2007 to 2015 (95% Confidence Interval)|
|Non-Hispanic white||14.4 (13.8-15.0)|
|Non-Hispanic black||8.0 (7.5-8.5)|
|No degree||7 (6.6-7.3)|
|HS or GED||12.5 (11.9-13.1)|
|Some college||13.3 (12.6-13.9)|
|Bachelor or higher||17.8 (17.0-18.7)|
|Poor (≤100% of FPL)||7.1 (6.8-7.5)|
|Near poor (100%-124% of FPL)||9.9 (9.1-10.7)|
|Low-income (125%-199% of FPL)||10.1 (9.5-10.6)|
|Middle-income (200%-399% of FPL)||11.1 (10.5-11.6)|
|High-income (>399% of FPL)||15.1 (14.5-15.7)|
|Public (Medicaid/Medicare)||13 (12.4-13.6)|
Of patients with a self-reported ophthalmologic condition, 57.5% had at least 1 visit to an outpatient ophthalmologist from 2007 to 2015. The percentage of patients with at least 1 visit to an outpatient ophthalmologist differed for patients with cataract surgeries (81.7%), glaucoma (77.0%), retinal detachment and retinopathy (81.1%), other inflammatory conditions of the eye (30.4%), and blindness (47.7%) ( Table 2 ).
|Self-Reported Ophthalmologic Condition||Percent Receiving ≥1 Outpatient Ophthalmologist Visit From 2007 to 2015 (95% Confidence Interval)|
|No ophthalmologic condition||7.1 (6.8-7.5)|
|Any ophthalmologic condition||57.5 (56.2-58.8)|
|Retinal detachments; defects; vascular occlusion; and retinopathy||81.1 (78.9-83.3)|
|Inflammatory condition of the eye||30.4 (28.3-32.4)|
|Other condition of the eye||64.9 (63.2-66.7)|
|Self-reported overall health|
|Very good||12.4 (11.8-13.0)|