Concurrent associations between objective markers and subjective markers of aging with indicators of successful...

Cognitive decline, immune function, and inflammation are considered objective markers of aging (OMAs) and are commonly used to predict an individual's aging success. We propose that subjective factors - such as a person's beliefs and perceptions about their own age and aging - that have been shown to predict development in old age be defined as subjective markers of aging (SMAs). Although aging is a complex, multidimensional process, studies typically examine effects of OMAS and SMAs separately, rather than integrating both types of markers to improve predictions of successful aging. Our study aims to fill this gap by concurrently using both OMAs and SMAs to model the associations of different indicators of successful aging, including autonomous daily functioning, health-related quality of life, and life satisfaction. We assess OMAs through measures of visuo-motoric speed and executive function (Trail Making Test), inflammation (interleukin-6, c-reactive protein), and immune aging (neutrophil-to-lymphocyte ratio). In addition, we examine SMAs by evaluating subjective age and self-perceptions of aging. We used cross-sectional data from 456 older adults (M_Age = 74 years, 60-86 years) from the LIFE Adult Study to investigate the associations of OMAs and SMAs with successful aging. Regarding OMAs, cognitive functioning and inflammation were associated to daily activities and health-related quality of life, respectively, but were not related to life satisfaction. In contrast, both SMAs were associated to life satisfaction, and self-perceptions of aging were associated to health-related quality of life, but none of the SMAs were related to levels of daily functioning. Our results suggest that fundamental biological resources and psychological perceptions of aging are selectively associated with different facets of successful aging.