142nd APHA Annual Meeting and Exposition

Annual Meeting Recordings are now available for purchase

309294
Visual Acuity and Increased Mortality: The Role of Allostatic Load and Functional Status

142nd APHA Annual Meeting and Exposition (November 15 - November 19, 2014): http://www.apha.org/events-and-meetings/annual
Monday, November 17, 2014 : 2:50 PM - 3:10 PM

D Diane Zheng, MS , Department of Public Health Science, University of Miami Miller School of Medicine, Miami, FL
Sharon Christ, PhD , Department of Human Development and Family Studies and Statistics, Purdue University, West Lafayette, IN
Byron Lam, MD , Bascom Palmer Eye Institute, University of Miami, Miami, FL
Stacey L. Tannenbaum, PhD, RD, LD/N , Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, FL
Christine Bokman , Miller School of Medicine, University of Miami, Miami, FL
Kristopher L. Arheart, EdD , Department of Public Health Sciences, University of Miami Miller School of Medicine, Miami, FL
Laura A. McClure, MSPH , Department of Epidemiology & Public Health, University of Miami, Miller School of Medicine, Miami, FL
Cristina Fernandez, MSEd , Department of Epidemiology and Public Health, University of Miami Miller School of Medicine, Miami, FL
David J. Lee, PhD , Department of Public Health Sciences, University of Miami Miller School of Medicine, Miami, FL
BackgroundPoor vision may detrimentally impact functional status and affect allostatic load (AL), a measure of cumulative physiological wear and tear on the body's regulatory systems. We examined the direct and indirect effects of visual acuity (VA) on mortality through functional status and AL in older adults.

 

Methods: Data from 4,981 participants (age >60 years) from the 1999-2004 National Health and Nutrition Examination Survey with mortality linkage through 2006 were analyzed. Functional status was assessed by Activities of Daily Living (ADL) and Instrumental Activities of Daily Living (IADL). The AL index was comprised of 10 biomarkers and anthropometric measures. VA was categorized as: none (20/20-20/25), mild (20/30-20/40), moderate (20/50-20/80), severe (≥20/200). Structural equation modeling using three mediating variables representing ADL, IADL and AL examined the effects of VA on all-cause mortality.

 

Results: Adjusting for all covariates, a one-unit change in VA category increased mortality risk (HR=1.17; 95% CI [1.05,1.32]); IADL and AL predicted mortality (HR=1.15; [1.10,1.20] and HR=1.13; [1.06,1.20], respectively). ADL did not predict mortality (HR=0.98; [0.91,1.05]). Worse VA was associated with increased AL (β =0.11; p=0.013) and worse IADL (β =1.06; p<0.001). Worse VA increased mortality risk indirectly through IADL (HR=1.07; [1.03,1.12]) and AL (HR=1.11; [1.06,1.17]). The total effect of VA on mortality including through IADL and AL was (HR=1.27; [1.12,1.44]).

 

Conclusions: Al and IADL may function as mediators between VA impairment and mortality. Older adults with VA impairment could potentially benefit from interventions designed to improve AL levels or IADL functional status to reduce the risk of mortality.

Learning Areas:

Epidemiology

Learning Objectives:
Identify possible mechanisms visual impairment impacts mortality. Describe the relationships between visual impairment, allostatic load, functional status and mortality in older adults. Assess the direct and indirect effect of visual acuity impairment has on mortality through allostatic load and functional status.

Keyword(s): Vision Care, Mortality

Presenting author's disclosure statement:

Qualified on the content I am responsible for because: I have been working in the field of ocular Epidemiology for more than 13 years. I have a master's degree in Biostatistics and have co-authored over 20 peer review papers in topics related to visual impairment.
Any relevant financial relationships? No

I agree to comply with the American Public Health Association Conflict of Interest and Commercial Support Guidelines, and to disclose to the participants any off-label or experimental uses of a commercial product or service discussed in my presentation.