Biological risk of older adults with visual impairments

To investigate whether biological markers of health differ among older adults with visual impairment compared to those with normal vision.

We use data from the National Health and Nutrition Examination Survey (1999 - 2006) to investigate clinically defined at-risk levels for 10 biological markers.

Survey participants were non-institutionalized.

Nationally representative (U.S.) sample of older adults age 65 and older, categorized as having blindness (20/200 or worse), low vision (20/40 to 20/100) or normal vision (better than 20/40).

Separate binary logistic regressions (one for each biomarker, with two at-risk cut points for BMI: obese and underweight) were computed to determine the odds of having at-risk levels of each biomarker.

Biomarkers included: systolic and diastolic blood pressure, high-density lipoprotein, low-density lipoprotein (LDL) cholesterol, total cholesterol, glycated hemoglobin, body mass index (BMI), fasting triglycerides, C-reactive protein, and plasma homocysteine.

Older adults who were blind were more likely to have high-risk levels of LDL cholesterol, homocysteine, and to be underweight (BMI>18.5). Similarly, older adults with LV were more likely to have high-risk levels of homocysteine compared to older adults with normal vision.

As several of the high-risk biomarkers associated with visual impairment were diet-related, our results suggest the importance of nutrition and diet programs aimed towards educating older people who are visually impaired.