A new cohort study examines confounding trends in the challenges of reduced mortality among China’s elderly population. The dynamics of two coexisting, opposing trends point to complex contributing socioeconomic factors in individuals’ overall health status.
Modern technological and healthcare advancements coincide with reduced mortality rates around the world. However, growing global populations of the ‘oldest-old’ require continued care to address cognitive and physical issues accompanying age. As more people live longer due to improved living conditions in their areas, demands for policies and programs designed to meet their urgent social and healthcare needs are rapidly increasing.
A recent study in The Lancet (2017) was the first of its kind to engage the world’s “largest dataset of oldest-old cohorts” from a low or middle-income country. This comparative study analyzed the data of 19,528 individuals in China, divided into cohorts from ages 80-89, 90-99, and 110-105 in order to identify rates of mortality, self-reported disability as it related to activities of daily living, physical function, and cognitive function levels. Researchers also readjusted data to compare results against major Chinese socioeconomic factors such as age, rural versus urban residence, education, and marital status.
In both 1998 and 2008, trained interviewers for the Chinese Longitudinal Healthy Longevity Survey (CLHLS) conducted in-home interviews with elderly participants to assess physical and cognitive function. Researchers used this data to compare the three cohort groups. Results showed that rates of mortality and disability were significantly reduced among later cohorts in comparison to those belonging to the group born 10 years earlier. However, objective measures of cognitive and physical function were substantially worse for later cohorts than earlier ones.
These later cohorts may have benefited from healthcare treatment advances, lifestyle modifications, less debilitating effects of chronic illness, and overall improved living conditions accompanying socioeconomic development, which reduced mortality and postponed cognitive decline. However, more of those individuals also recorded having survived life-threatening conditions that adversely affected their physical health. Furthermore, measurements of disability with regard to activities of daily living, such as bathing, depend on rapidly changing standards of living and facilities made available to individuals.
Limitations of this study further underscore its significance as resources were unavailable to provide more in-depth analysis on the numerous causal links between mortality, disability, and reductions in physical and cognitive function. This study highlights the importance of gaining a deeper understanding of socioeconomic factors and their effects on individual health. Just as childhood living conditions and education play a role in rates of cognitive function later in life, access to healthcare and social programs for the oldest-old are crucial to maintaining quality of life in the face of physical and cognitive decline with age.
Further research is required to investigate specific contributing factors to overall health and challenges of reduced mortality as populations continue to age. This vital information may inform policy and programming to provide social and health care services to elderly populations around the world.
Written By: Jennifer Newton