New CDC Research Investigates the Association Between Vision Loss and Quality of Life

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A major new study from the National Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention (CDC) has investigated the association between visual impairment and health-related quality of life among adults aged 65 and older.

The research concludes that poor health-related quality of life is strongly associated with the severity of self-reported visual impairment among people aged 65 and older who participated in the study. Participants who reported “moderate/severe” visual impairment showed a strong, consistent association with poor health-related quality of life.

From Ophthalmic Epidemiology

Head shot of Dr. John E. Crews

The research, entitled Health-Related Quality of Life Among People Aged ≥65 Years with Self-reported Visual Impairment: Findings from the 2006–2010 Behavioral Risk Factor Surveillance System, has been published in the October 2014 edition of Ophthalmic Epidemiology, which encompasses the epidemiological, clinical, educational, environmental, and cultural aspects of eye disease, prevention of blindness, preservation of sight, and visual rehabilitation.

[Editor’s note: Epidemiology is a branch of medical science that studies the incidence, distribution, and control of disease in a population. It forms the cornerstone of public health and informs policy decisions and evidence-based health practice.]

The authors are John E. Crews; Chiu-Fang Chou; Xinzhi Zhang; Matthew M. Zack; and Jinan B. Saaddine, from the National Center for Chronic Disease Prevention and Health Promotion, CDC, Atlanta, Georgia.

Lead author John E. Crews, DPA (pictured above left), is a Health Scientist with the Vision Health Initiative of the CDC’s National Center for Chronic Disease Prevention and Health Promotion. Dr. Crews’s specialties are vision impairment and aging, caregiving, and disability. His research interests also include health disparities among people with disabilities, and aging with a disability.

Some Background: The CDC Behavioral Risk Factor Surveillance System

The CDC’s Behavioral Risk Factor Surveillance System (BRFSS) is the world’s largest ongoing telephone health survey system, tracking health conditions and risk behaviors in the United States yearly since 1984. Currently, data are collected monthly in all 50 states, the District of Columbia, Puerto Rico, the U.S. Virgin Islands, and Guam.

The BRFSS Vision Module was developed by CDC’s Vision Health Initiative. Nineteen states have begun using it since its implementation in 2005. The Vision Module surveys adults aged 40+ and contains nine questions about visual function, eye diseases, frequency of eye examinations, and reasons for not seeking eye care.

First, the Research Summary

From the article abstract:

Purpose: To examine the association between health-related quality of life and visual impairment among people aged ≥65 years [i.e., greater than or equal to 65 years old].

Methods: We used cross-sectional data from the 2006–2010 Behavioral Risk Factor Surveillance System to examine six health-related quality of life measures: (a) self-reported health, (b) physically unhealthy days, (c) mentally unhealthy days, (d) activity limitation days, (e) life satisfaction, and (f) disability. Visual impairment was categorized as (a) no, (b) a little, and (c) moderate/severe.

[Editor’s note: A cross-sectional study involves an analysis of a population of subjects at one specific point in time, rather than studied over a longer, or more extended, period of time.]

Results: People with self-reported moderate/severe visual impairment had more frequent (≥14) [i.e., greater than or equal to 14] physically unhealthy days, mentally unhealthy days, and activity limitation days in the last 30 days compared to those reporting “a little” or “no” visual impairment.

After controlling for all [variables] (age, sex, marital status, race/ethnicity, education, income, diabetes, heart disease, stroke, heart attack, body mass index, leisure time activity, smoking, and medical care cost concerns) and comparing to those with no self-reported visual impairment, people reporting “a little” visual impairment were more likely to have fair/poor health; life dissatisfaction; and disability.

Those with self-reported “moderate/severe” visual impairment had more fair/poor health; life dissatisfaction; and disability. They also had more frequent physically unhealthy days; mentally unhealthy days; and activity limitations days.

Conclusion: Poor health-related quality of life is strongly associated with the severity of self-reported visual impairment among people aged ≥65 years [i.e., greater than or equal to 65 years old].

Highlights from the Research

Characteristics of the Study Subjects

  • Among the study population, 54% were aged 65–74 years, 58% were women, 7.4% were non-Hispanic black, and 6.0% were Hispanic.
  • Compared to those reporting no visual impairment, more women, non-Hispanic blacks, Hispanics, those with less education, and those with annual household incomes below $35,000 reported moderate/severe visual impairment.
  • Increased severity of self-reported visual impairment was consistently associated with four chronic conditions: diabetes, heart disease, stroke, and heart attack.
  • Increased severity of self-reported visual impairment was also associated with worse health-related quality of life.

Difficulties in Defining and Measuring “Quality of Life”

  • Quality of life research has moved from measures of necessities for food and shelter to measures of “fulfillment and personal happiness,” reflecting social priorities and changing outcomes in medicine.
  • The World Health Organization quality of life instrument, for example, defines quality of life as “an individual’s perception of their position in life in the context of the culture and value systems in which they live and in relation to their goals, expectations, standards and concerns.”
  • The CDC’s health-related quality of life questions, on the other hand, address “an individual’s or group’s perceived physical and mental health over time.” Therefore, the CDC quality of life measures range from general well-being, to task performance, to overall physical and mental health.
  • Each concept measures important – but different – quality of life characteristics.

The Presence of Multiple Health Problems among People with Visual Impairment

  • The study findings also reveal the significance of multiple chronic health conditions among people with visual impairment. The study participants who reported having heart disease, heart attack, diabetes, and stroke also reported poorer health-related quality of life.
  • After controlling for these health conditions in the research, however, visual impairment was still associated with poorer health-related quality of life.
  • Thus, it is extremely important to recognize and address the effects of visual impairment on many aspects of health and quality of life.

Looking at Vision Loss from a Public Health Point of View: Study Recommendations

As the authors note in the study conclusions,

From a public health point of view, addressing the six CDC health-related quality of life measures may identify potential pathways to improve overall health-related quality of life, especially among those reporting the most severe visual impairment.

For example, ample evidence exists demonstrating that improved access to eye care results in positive health outcomes. Refractive error [i.e., needing eyeglasses] remains a substantial problem for older people, but Medicare does not pay for [eyeglasses], and those reporting more severe visual impairment indicate greater concerns for health care costs.

While removing impediments to access to eye care and health care lead to positive health outcomes, further research could identify whether additional gains in health-related quality of life may occur by addressing health promotion and health behaviors targeting those with visual impairment.

Our findings show that people with moderate/severe self-reported visual impairment had higher prevalence of chronic conditions, obesity, current smoking, and lack of leisure-time physical activity. Altering health promotion interventions and promoting health behaviors to include people with vision problems might lead to better health-related quality of life outcomes. Health promotion materials in large print or electronic formats might improve participation.

Similarly, efforts to improve health behaviors, like being physically active, might include improved availability of sidewalks and better illumination to promote walking.

These avenues have not been rigorously investigated and require additional attention, but … tailored interventions might lead to improved self-reported health, fewer physically unhealthy days, fewer mentally unhealthy days, and improved life satisfaction.

Additional Information