Mark W. Swanson

Visual impairment and functional status from the 1995 National Health Interview Survey on Disability

purpose The purpose of this project is to evaluate the association of vision limitation and function among a population of older and younger adults. methods The effects of self-reported serious difficulty with vision and legal blindness were evaluated on six activities of daily living (ADLs) and six instrumental activities of daily living (IADLs). Subjects were 67,570 adults over the age of 18 who participated in the 1995 National Health Interview Survey on Disability. results Serious difficulty with vision (SDV) and legal blindness (LB) were independently associated with increased odds of poorer function for each of the ADLs and IADLs. In stratified analysis, the effect of vision on function was modified by age. Both SDV and LB produced a greater impact on performance of ADLs and IADLs among younger rather than older subjects. conclusions Vision had an impact on all ADLs and IADLs evaluated, with greater impact on self-reported function for younger adults. This suggests that younger adults perceive limitations associated with visual disability differently than do older adults.

A cross-sectional analysis of U.S. contact lens user demographics.

Purpose. Large population studies carried out in the United States, while addressing refractive error prevalence, have published little addressing the modes of refractive correction. As such, there are little data in the biomedical literature concerning the characteristics of the contact lens wearing population in the United States. The purpose of this project was to develop estimates of the demographic characteristics of a cross section of contact lens wearers in the United States based on those who wore contact lenses on the day of their National Health and Nutrition Examination Survey (NHANES) examination. Methods. The NHANES is a nationally representative sample of the U.S. population. As part of NHANES, the type of refractive correction used is collected during a mobile medical clinic examination along with demographic variables. Data files from the 2005–2006 and 2007–2008 NHANES were obtained from the National Center for Health Statistics. Demographic characteristics of the U.S. population using contacts during the medical clinic examination were derived. Associations between demographic variables and contact lens use were explored in age-stratified univariate and multivariate analyses taking into account the complex sampling frame. Results. In univariate analysis, age (p < 0.001) and the availability of health insurance (p = 0.007) have negative associations with contact lens use, while female gender (p < 0.001), higher socioeconomic status (p < 0.001), and higher educational attainment (p < 0.001) are associated with increased contact lens use. In multivariate analysis, age (p < 0.001), socioeconomic status (p < 0.001), the interaction of age with gender (p < 0.001), and the interaction of socioeconomic status with education (p = 0.002) are associated with contact lens use. Conclusions. Four demographic variables, age, socioeconomic status, age-gender interaction, and socioeconomic status-education interaction, defined those likely to be using contact lens on any given day in the United States. Together, these four variables identify almost 9 of 10 contact lens users.

The Nursing Home Minimum Data Set for Vision and Its Association with Visual Acuity and Contrast Sensitivity

OBJECTIVES: To evaluate the association between the Minimum Data Sets (MDS) Vision Patterns section and near and distance visual acuity and contrast sensitivity in nursing home residents.

Academic Difficulty and Vision Symptoms in Children with Concussion.

PURPOSE Academic difficulty is reported in children with prolonged post-concussive symptoms. Despite growing evidence that vestibular-ocular and vision-specific dysfunction are common in children after concussion, vision is rarely mentioned in return-to-learn protocols. The purpose of this project was to evaluate a cohort of children with prolonged post-concussive symptoms to determine if vision symptoms are associated with those reporting academic difficulty. METHODS Data were obtained from the Childrens of Alabama Concussion Clinic REDCap dataset from the period January 2007 to October 2013. From this dataset of 1033 concussion events, a cohort of 276 children aged 5 to 18 years with three or more concussion-related symptoms present for 10 days or more was identified. A cross-sectional cohort study was undertaken to evaluate the association of concussion symptoms, SCAT2 scores, and demographic and concussion severity markers to reported educational difficulty among children with prolonged post-concussive symptoms. Univariate and multivariate logistic regression techniques were used to model the association of reported educational difficulty to self-reported vision abnormalities. RESULTS Mean age was 13.8 years. Median time since the concussive event was 21 days, with 33% (95/276) reporting their concussion more than 30 days before data collection. Academic difficulty was reported by 29% (79/270) and vision abnormalities in 46% (128/274). After model reduction, vision symptoms (OR 2.17, 95% CI 1.02, 4.62), hearing disturbance (OR 2.39, 95% CI 1.06, 5.36), and concentration difficulty (OR 21.62, 95% CI 9.50, 44.47) remained associated with academic difficulty. For those with symptoms 30 days or more after concussion, only vision (OR 3.15, 95% CI 1.06, 9.38) and concentration difficulty (OR 15.33, 95% CI 4.99, 47.05) remained statistically significant. CONCLUSIONS Vision problems were commonly reported in children with concussions and were independently associated with those reporting academic difficulty. Comprehensive vision assessment should be considered in children reporting academic difficulty and in the development of return-to-learn protocols.

Creation of an Interprofessional Clinical Experience for Healthcare Professions Trainees in a Nursing Home Setting

Successful interprofessional teams are essential when caring for older adults with multiple complex medical conditions that require ongoing management from a variety of disciplines across healthcare settings. To successfully integrate interprofessional education into the healthcare professions curriculum, the most effective learning experiences should utilize adult learning principles, reflect real-life practice, and allow for interaction among trainees representing a variety of health professions. Interprofessional clinical experiences are essential to prepare future healthcare professionals to provide quality patient care and understand the best methods for utilizing members of the healthcare team to provide that care. To meet this need, the University of Alabama at Birmingham Geriatric Education Center has developed an Interprofessional Clinical Experience (ICE) to expose future healthcare providers to an applied training experience with older adults in the nursing home setting. This paper outlines how this program was developed, methods used for program evaluation, and how the outcome data influenced program revisions.

The 97.5th and 99.5th percentile of vertical cup disc ratio in the United States.

Purpose. The International Society of Geographical and Epidemiological Ophthalmology (ISGEO) suggests a case definition for the prevalence studies of glaucoma based on the 97.5th and 99.5th percentile of vertical optic cup distribution among the evaluated population. Although multiple studies evaluating the prevalence of glaucoma have been undertaken in the last 20 years, case definitions have varied, and data on the underlying population distribution are sparse. This study evaluates the population distribution of 97.5th and 99.5th percentile of vertical cup disc ratio (VCDR) and VCDR asymmetry (VCDRA) in the US population and its association with demographic characteristics, self-reported glaucoma, and visual field. Methods. The National Health and Nutrition Examination Survey (NHANES) is a nationally representative sample of the US population, which during the years 2005 to 2008 collected frequency doubling technology screening fields and digital fundus photography. Accounting for the complex design of the NHANES population, estimates of the 97.5th and 99.5th percentile of VCDR and VCDRA were calculated, and national estimates of glaucoma prevalence were generated. Associations between disc characteristics, demographic variables, and self-reported glaucoma were explored. Results. Approximately 2.11% (95% confidence interval, 1.55 to 2.67) of the US population older than 40 years has glaucoma based on ISGEO criteria. A much larger 5.13% (95% confidence interval, 4.43 to 5.85) of the US population older than 40 years self-reports having glaucoma. Based on the estimates from NHANES, 6.89% of the population has a VCDR or VCDRA >97.5th percentile in either eye or OU. For the at-risk population with VCDR/VCDRA above the 97.5th percentile, <20% reported having glaucoma, whereas for those at the 99.5th percentile, <50% reported having glaucoma. Conclusions. The prevalence of glaucoma from NHANES based on ISGEO criteria produces similar population estimated to other population-based studies. Self-reported glaucoma is ∼2.4 times more common than what the prevalence estimates suggest.

Smoking deception and age-related macular degeneration.

Purpose Smoking has been identified as a major modifiable risk factor for age-related macular degeneration (AMD). Smoking deception or failing to self-report as a smoker is a recognized concern among studies of smoking-related disease. To date, no studies have evaluated the rates of smoking deception in macular degeneration. Methods Data from the 2005 to 2008 National Health and Nutrition Examination Survey were used to produce estimates of smoking deception among three ethnic groups within the US population. Comparisons of self-reported rates of cigarette use, any nicotine product use, and serum cotinine levels were used to produce estimates of potential smoking deception among adults older than 40 years with any-level macular degeneration and those at risk of late-stage disease. Results Any-level AMD was found to be present in 6.7% (95% confidence interval [CI] = 5.6% to 7.8%) of this cohort. Excluding those with late AMD, 9.7% (95% CI = 8.3% to 11.0%) were at risk of developing late-stage disease. Among individuals with any level of macular degeneration, 5.4% (95% CI = 2.1% to 8.6%) were potential smoking deceivers. A similar rate was seen among those at risk of late-stage disease at 5.0% (95% CI = 2.3% to 7.6%). Conclusions The rate of possible smoking deception seems higher for macular degeneration and those at risk of late-stage AMD than is generally reported in the US population. While the deception rate is low at the individual level, as many as 450,000 adults in the US population at risk of late-stage AMD may misclassify their smoking status.

Anti-inflammatory drug use and age-related macular degeneration.

Purpose. Basic research has shown that early processes in the development of age-related macular degeneration (ARMD) are related to inflammation. The purpose of this manuscript is to evaluate the association of ARMD and the use of anti-inflammatory medications. Methods. A nested case control study was carried out among male patients at the Veteran’s Medical Center in Birmingham, Alabama (BVAMC). Cases were 614 patients with incident ARMD diagnosed between 1997 and 2001 by International Classification of Disease, Ninth Revision code. Controls (4526) were individuals with no diagnosis of ARMD by International Classification of Disease, Ninth Revision coding and matched on age. Formulary records of all medications dispensed through the Veteran’s Administration Medical Center were accessed. All oral or injectable drugs with anti-inflammatory properties were considered anti-inflammatory medications for study purposes. Topical ophthalmic and dermatologic preparations were not considered anti-inflammatory. Results. Among veterans with a diagnosis of ARMD 24% (150/614) patients had filled a prescription for any of the anti-inflammatory medications compared with 60% (3051/4526) individuals in the control population. Individuals who had filled a prescription for anti-inflammatory drugs had an 85% reduced odds of having a diagnosis of ARMD (odds ratio 0.15, 95% confidence interval 0.12–0.18). Conclusions. The results of this study suggest that veterans who had filled a prescription for anti-inflammatory medications had a reduced risk of ARMD. Further studies are needed to confirm this result.

Nystagmus in pediatric patients: interventions and patient-focused perspectives

Nystagmus refers to involuntary, typically conjugate, often rhythmic oscillations of the eyes. The most common cause of nystagmus in children is infantile nystagmus syndrome (INS). INS presents within the first few months of life and is sometimes accompanied by an ocular condition associated with sensory impairment. Because this condition affects a person throughout life, it is important to understand the options available to manage it. This review focuses on the underlying nystagmus etiology, psychosocial and functional effects of nystagmus, as well as current principles of management, including optical, pharmacological, surgical, and rehabilitative options. Currently, the neural mechanisms underlying INS are not fully understood. Treatment options are designed to increase foveation duration or correct anomalous head postures; however, evidence is limited to mainly pre- and post-study designs with few objective comparisons of treatment strategies. Management of INS should be individualized. The decision on which treatment is best suited for a particular patient lies with the patient and his/her physician.

King-Devick and Pre-season Visual Function in Adolescent Athletes.

PURPOSE The King-Devick test (KD) has been studied as a remove-from-play sideline test in college-age athletes and older; however, studies in younger athletes are limited. A cross-sectional study of the KD and other vision correlates was completed on school-aged athletes during pre-season physicals for a variety of sports to determine the repeatability of the KD. The study also evaluated how convergence, alignment, or pupil function contributed to a slower King-Devick baseline reading. METHODS Seven hundred eighty-five athletes underwent vision screenings in a hospital or school setting by trained/certified staff as part of pre-season physicals. Six hundred nineteen had KD testing completed per the manufacturers suggested protocol and repeated. Other baseline vision testing included visual acuity, Modified Thorington testing for alignment, convergence testing, and pupil function using the NeurOptics (NPI-200) NPi. RESULTS The mean fastest, error-minimized KD time for all participants was 43.9 seconds(s) (SD ± 11.6, range 24-120). Median KD time got faster (+) with age (p < 0.0001). The inter-class correlation coefficient for all scores was 0.92. The absolute mean time difference for any two tests was 3.5 s (SD ± 2.5, range 0-23). There was no association between the best KD time and reduced NPC (p = 0.63), Modified Thorington measure of alignment (p = 0.55), or NPi pupil function (p = 0.79). The Bland Altman repeated measure limits of agreement was ±6.5 seconds for those in the 10th to12th grades, and ±10.2 seconds for those in the 6th to 9th grades. CONCLUSIONS King-Devick score in junior high and high school athletes is variable but gets faster and more repeatable with increasing age. The KD does not correlate significantly with reduced convergence, alignment, or pupil function. Based on grouped data, a slowing of 10 seconds for younger athletes and 6 seconds for older athletes on a second administration represents a true difference in testing speed. Within-player variability should be considered when removal-from-play decisions are influenced by KD results.