D. Diane Zheng

Prevalence of concurrent hearing and visual impairment in US adults: The National Health Interview Survey, 1997-2002.

Analysis of data from a nationally representative sample of US adults (n=195801) showed that concurrent hearing and visual impairment prevalence rates were highest for participants older than 79 years of age (16.6%); a 3-fold increase in age-adjusted rates of reported hearing and visual impairment was observed for Native Americans compared with Asian Americans. Research on preventing concurrent hearing and visual impairment and countering its consequences is warranted, especially in population subgroups, such as Native and older Americans.

Glaucoma and survival: The National Health Interview Survey 1986–1994

OBJECTIVE Associations between glaucoma and survival have not been studied extensively, in part, because of the relatively low prevalence of this condition. This study examines associations between self-reported glaucoma and mortality in a nationally representative sample of U.S. adults. DESIGN Annual cross-sectional multistage area probability survey of the U.S. civilian noninstitutionalized population living at addressed dwellings. PARTICIPANTS Mortality linkage with >96% of participants from the 1986 to 1994 National Health Interview Survey was performed by the National Center for Health Statistics through 1997. Complete data were available on 116796 adults >or=018 years old. METHODS Adults within randomly selected households were administered a chronic conditions list that included questions about glaucoma and visual impairment. Proxy information on these conditions was obtained when household members were unavailable for interview. Statistical methods included Cox regression models with adjustments for covariates, as well as for the complex sample survey design. MAIN OUTCOME MEASURE All-cause mortality and cardiovascular and cancer mortality. RESULTS A total of 1559 (1.3%) glaucoma cases were reported. Nearly 19% of participants with reported glaucoma also had reported visual impairment (n = 303). Mortality linkage identified 8949 deaths; the average follow-up was 7.0 years. After controlling for survey design, gender, age, race, marital status, education level, and self-rated health, participants with reported glaucoma but without reported visual impairment were at significantly increased risk of death relative to participants without reported glaucoma, irrespective of visual impairment status (hazard ratio [HR], 1.35; 95% confidence interval [CI], 1.19-1.53); similar associations were found for participants with reported glaucoma and visual impairment vs. participants with no reported glaucoma (HR, 1.39; 95% CI, 1.14-1.71). An increased risk of cardiovascular disease mortality was found for participants with reported glaucoma both without (HR, 1.31; 95% CI, 1.11-1.55) and with (HR, 1.53; 95% CI, 1.15-2.05) reported visual impairment. Risk of mortality due to cancer was increased only in participants with reported glaucoma but without reported visual impairment (HR, 1.57; 95% CI, 1.25-1.98); this association was stronger when the mortality analysis was restricted to cancers amenable to early screening, including breast, cervical, colon, and prostate cancer (HR, 1.99; 95% CI, 1.41-2.81). CONCLUSIONS Among adults residing in the United States, reported glaucoma is associated with an increased risk of all-cause and cardiovascular disease mortality. Associations between glaucoma and cancer were inconsistent and may reflect, in part, a detection bias, in which glaucoma is more likely to be diagnosed in adults receiving health care because of other medical conditions.

Reported Eye Care Utilization and Health Insurance Status Among US Adults

OBJECTIVES To estimate prevalence and correlates of eye care utilization by means of data from the National Health Interview Survey. METHODS Nearly 290,000 adults 18 years or older participated in the survey from 1997 through 2005. Eye care utilization was based on self-reported contact with an eye care professional in the past year. Participants were classified by level of visual impairment based on response to 2 questions. The survey and logistic regression procedures in SAS statistical software were used to compute 1997 through 2005 pooled eye care utilization rates and to identify correlates of utilization. RESULTS Overall eye care utilization rates were 58.3%, 49.6%, and 33.7%, respectively, for participants with severe, some, and no visual impairment; rates for respondents without health insurance were 35.9%, 23.8%, and 14.3%, respectively. Multivariable logistic regression analyses completed in racial/ethnic and age category subgroups indicated that no reported visual impairment, lack of health insurance, male sex, and low education were associated with low eye care utilization rates. CONCLUSIONS Interventions designed to increase eye care utilization rates in select sociodemographic subgroups are needed. Overall utilization rates may also be enhanced if progress is made toward dramatically increasing the number of Americans with health insurance.

Assessment of the effect of visual impairment on mortality through multiple health pathways: Structural equation modeling

PURPOSE To estimate the direct effects of self-reported visual impairment (VI) on health, disability, and mortality and to estimate the indirect effects of VI on mortality through health and disability mediators. METHODS The National Health Interview Survey (NHIS) is a population-based annual survey designed to be representative of the U.S. civilian noninstitutionalized population. The National Death Index of 135,581 NHIS adult participants, 18 years of age and older, from 1986 to 1996 provided the mortality linkage through 2002. A generalized linear structural equation model (GSEM) with latent variable was used to estimate the results of a system of equations with various outcomes. Standard errors and test statistics were corrected for weighting, clustering, and stratification. RESULTS VI affects mortality, when direct adjustment was made for the covariates. Severe VI increases the hazard rate by a factor of 1.28 (95% CI: 1.07-1.53) compared with no VI, and some VI increases the hazard by a factor of 1.13 (95% CI: 1.07-1.20). VI also affects mortality indirectly through self-rated health and disability. The total effects (direct effects plus mediated effects) on the hazard of mortality of severe VI and some VI relative to no VI are hazard ratio (HR) 1.54 (95% CI: 1.28-1.86) and HR 1.23 (95% CI: 1.16-1.31), respectively. CONCLUSIONS In addition to the direct link between VI and mortality, the effects of VI on general health and disability contribute to an increased risk of death. Ignoring the latter may lead to an underestimation of the substantive impact of VI on mortality.

Reported Visual Impairment and Risk of Suicide The 1986-1996 National Health Interview Surveys

OBJECTIVE To examine the relationship between reported visual impairment and suicide mortality. METHODS From 1986 through 1996, annual cross-sectional multistage area probability surveys of the US civilian noninstitutionalized population living at addressed dwellings were conducted by the National Center for Health Statistics. We performed mortality linkage through 2002 with the National Death Index of 137,479 adults 18 years and older. The relationships between reported visual impairment and suicide were examined using structural equation modeling. RESULTS The mean duration of follow-up was 11.0 years, and 200 suicide deaths were identified. After controlling for survey design, age, sex, race, marital status, number of nonocular health conditions, and self-rated health, the direct effect of visual impairment on death from suicide was elevated but not significant (hazard ratio, 1.50; 95% confidence interval, 0.90-2.49). The approximate indirect effect of visual impairment on death from suicide via poorer self-rated health (1.05; 1.02-1.08) or number of nonocular health conditions (1.12; 1.01-1.24) was significant. The total effect of visual impairment on death from suicide was elevated but not significant (1.64; 0.99-2.72). CONCLUSIONS Visual impairment may be associated with an increased risk of suicide through its effect on poor health. This suggests that improved treatment of visual impairment and factors causing poor health may potentially reduce suicide risk.

Severity of concurrent visual and hearing impairment and mortality: the 1986-1994 National Health Interview Survey.

Purpose: Visual impairment and, to a lesser extent, hearing impairment are independent predictors of reduced survival in selected studies of community-residing adults. To date, the association of severity of concurrent impairment and mortality has not been examined. Method: The National Health Interview Survey is a continuous, multistage, area probability survey of the U.S. civilian noninstitutionalized population. Mortality linkage with the National Death Index of 116,796 adult participants from 1986 to 1994 with complete impairment data was performed through 1997. Results: Findings indicate that moderate to severe concurrent hearing and visual impairment in women is associated with significantly increased risk of mortality. More modest mortality associations are evident for men and for adults with less severe impairments, irrespective of gender. Discussion: Prevention of severe visual and hearing impairment should be a national public health priority, especially given the aging of the U.S. population.

Visual Impairment and Morbidity in Community-Residing Adults: The National Health Interview Survey 1986-1996

Purpose: To examine the association between visual impairment (VI) and morbidity. Methods: Using pooled, annual population-based household interview survey data (n = 140,366) from the 1986–1996 National Health Interview Survey, covariate-adjusted, gender and age group specific logistic regression analyses were used to examine associations between VI and five morbidity indicators: restricted activity days, bed rest days, doctor visits, hospitalizations, and self-rated health. Results: After controlling for educational status, race and the number of reported non-ocular health conditions, fair or poor health status (compared to excellent, very good, or good health status) was generally more strongly associated with severe, bilateral VI (range of odds ratios [ORs]: 2.14–7.24) than with some VI (ORs: 1.45–2.21). Severe, bilateral VI was also associated with more frequent doctor and hospital visits among adults 18–64 years of age (range of ORs: 1.69–3.34), and restricted activity and bed rest days among males 45 years and older (range of ORs: 1.95–3.69). Conclusions: The present findings, in conjunction with other studies documenting the impact of VI on morbidity outcomes, indicate that an increased focus on the provision of eye care services will be necessary to address the growing burden of VI in aging societies.

Longitudinal relationships among visual acuity, daily functional status, and mortality: the Salisbury Eye Evaluation Study.

IMPORTANCE Determination of the mechanisms by which visual loss increases mortality risk is important for developing interventional strategies. OBJECTIVE To evaluate the direct and indirect effects of loss of visual acuity (VA) on mortality risk through functional status changes among aging adults. DESIGN, SETTING, AND PARTICIPANTS Prospective longitudinal study of a population-based sample of 2520 noninstitutionalized adults aged 65 to 84 years from September 16, 1993, through July 26, 2003, in the greater Salisbury area of Maryland. Participants underwent reassessment 2, 6, and 8 years after baseline. Mortality status was ascertained from linkage with the National Death Index through 2009. EXPOSURES Results of VA testing and self-reported functional status based on activities of daily living (ADL) and instrumental ADL (IADL). MAIN OUTCOMES AND MEASURE Mortality. RESULTS Worse VA levels at baseline were associated with an increased the risk for mortality (hazard ratio [HR], 1.16 [95% CI, 1.04-1.28]; P < .01) through their effect on lower IADL levels at baseline. Declines in VA over time were associated with increased mortality risk (HR, 1.78 [95% CI, 1.27-2.51]; P < .001) by way of decreasing IADL levels over time. Participants experiencing the mean linear decline in VA of 1 letter on the Early Treatment Diabetic Retinopathy Study acuity chart per year are expected to have a 16% increase in mortality risk during the 8-year study exclusively through associated declines in IADL levels. CONCLUSIONS AND RELEVANCE In this longitudinal study of older adults, VA loss adversely affected IADL levels, which subsequently increased the risk for mortality. Prevention of disabling ocular conditions, treatment of correctable visual impairment, and interventions designed to prevent the effect of visual impairment on IADL declines may all reduce mortality risk in aging adults.

Longitudinal Relationships among Visual Acuity and Tasks of Everyday Life: The Salisbury Eye Evaluation Study

PURPOSE To study the relationships among visual and physical function trajectories of aging adults. METHODS The community-based random sample consists of 2520 adults who were aged 65 to 84 years in 1993 to 1995 and reassessed 2, 6, and 8 years later. Presenting and best-corrected Early Treatment Diabetic Retinopathy Study visual acuity were obtained. Activities of daily living (ADLs) and instrumental ADLs (IADLs) were evaluated through survey instruments. Growth curve models were used to simultaneously estimate health trajectories and obtain associations among the trajectories while controlling for relevant covariates. RESULTS Best-corrected acuity (logMAR) worsened by an average of 0.013 (∼1 letter) annually. ADL difficulties increased by 0.22 standard deviations (SD) and IADL difficulties increased by 0.28 SD annually. Controlling for demographic and health covariates, visual acuity rates of decline correlated with rates of increase in ADL difficulties (r = 0.15, P = 0.05) and IADL difficulties (r = 0.41, P < 0.001). Acuity loss was significantly related to increases in ADLs for men (b = 0.039, P < 0.01), but not for women (b = 0.001, P > 0.9). The direct effects of acuity loss were strongest for IADLs where a 1-unit decline in acuity (logMAR) was associated with a 0.067 SD increase in IADL difficulties (P < 0.001) at baseline, and a 1-unit acuity decline (logMAR) per year resulted in a 0.10 SD unit increase in the rate of change in IADL difficulties (P < 0.001) per year. CONCLUSIONS Over time, increases in visual acuity loss were related to increased IADL difficulties in men and women and increases in ADL difficulties for men only. The findings support the importance of maintaining vision in older adults.

Visual impairment and unintentional injury mortality: the national health interview survey 1986–1994

PURPOSE To examine the relationship between reported visual impairment and unintentional injury mortality. DESIGN Mortality linkage study of a population-based survey. METHODS Mortality linkage through 1997 of 116,796 adult participants, aged 18 years and older, from the 1986 to 1994 National Health Interview Survey was analyzed with respect to reported visual impairment using Cox regression models. The average follow-up was 7.0 years, and 295 unintentional injury deaths were identified. After controlling for survey design, age, sex, and the presence and number of eye diseases, participants with severe, bilateral visual impairment were at increased risk of death relative to participants without visual impairment (hazard ratio: 7.4; 95% confidence interval: 3.0-17.8). CONCLUSIONS Our data provide evidence that severe, bilateral visual impairment is associated with an increased risk of unintentional mortality among adults in the United States.