Apolipoprotein E and measured physical and pulmonary function in older Taiwanese adults

The apolipoprotein E (ApoE) gene, which has three common alleles (ϵ2, ϵ3, and ϵ4), has been linked to a number of health outcomes and longevity. The ϵ2 allele has been reported to have neuroprotective effects, whereas the ϵ4 allele has been shown to be a risk factor for cardiovascular disease and Alzheimer's disease in various populations. The relationships between ApoE and mortality and ApoE and physical function, however, are not clear-cut. We used the Social Environment and Biomarkers of Aging Study (SEBAS) to examine the relationship between ApoE polymorphisms and physical and pulmonary function in approximately 1,000 Taiwanese adults aged 53 years and older in 2006. In the 2006 SEBAS wave, measures of physical function included self-reported difficulties with respect to activities of daily living (ADLs) and other physical function indicators, as well as performance-based measures of grip strength (kg), walking speed (m/s) over a distance of 3 m, and chair stand speed (stand/s). Peak expiratory flow (PEF; L/min) rate was also examined as an indicator of pulmonary function. We used logistic regression models to determine the association between ApoE and inability to complete each of the tests of physical and pulmonary function. These models revealed no significant association between ApoE carrier status and any of the indicators of function. Among participants able to complete a given task, we next used linear regression models to examine self-reported limitations with ADLs and performance on the given test by ApoE carrier status. Similarly, there were no significant relationships between ApoE carrier status and the measures of function. Our estimates provide further confirmation that the ApoE gene may not be a risk factor for functional decline among older Taiwanese adults.