Research On The Trends Of Elderly Health From The Perspective Of Life Course

ObjectiveThe 21 st century is an era of ageing in the worldwide,and China is facing an increasingly severe ageing trend.The problems related to elderly health have drawn much attention from the society.At the same time,health inequality and heterogeneity make the problems more complicated.Therefore,it is of great importance to understand the health status and trends of elders,to achieve the objectives of living longer and healthier.The aim of this study is to explore the trends of elderly health from the perspective of life course.From a macroscopic view,to explore the effects of age,period and birth cohort on the overall health trends of elders as well as the elderly health trends of gender and residence(refer to urban vs rural)stratification.From a microscopic view,to identify the heterogeneity of elderly health trajectories jointly with mortality probabilities and to explore factors related to the particular trajectories.MethodData was from eight surveys in 1998-2018 of the Chinese Longitudinal Healthy Longevity Survey.The elders aged 65 to105 years old from the surveys were selected as research subjects.The elderly health was assessed from four aspects: Activities of daily living(ADL),cognitive function,physical function and self-rated health.This study included longitudinal trend research and cohort research design.Firstly,this study described the basic information and health stauts of 81262 elders from eight surveys.Then,from a macroscopic view,adopting the longitudinal trend research design,this study used hierarchical age period cohort-cross-classified random effects models to explore the effects of age,period and birth cohort on the overall health trends of elders,as well as the health trends of gender and residence stratification.Finally,from a microscopic view,adopting the longitudinal cohort research design,this study used group-based trajectory models to identify the heterogeneity of elderly health trajectories jointly with mortality probabilities and to explore factors related to the particular trajectories from the aspects of demographic characteristics,socioeconomic status and childhood characteristics.The statistical software used included SPSS 20.0 and SAS 9.4.P-values less than 0.05 were considered statistically significant.ResultsAge,period,and cohort effects on elderly health trends:Overall elderly health trends: ADL,cognitive function and physical function decreased with age in an increasing rate.Self-rated health deteriorated with age and then improved.The period effects showed that all of the four health indicators decreased from 1998 to 2002,and then cognitive function,physical function and selfrated health remained stable,ADL fluctuated slightly.The cohort effects were not significant and relatively stable.Sex-stratification health trends: After controlling for age,period and cohort effects,females had worse health status than males.For most indicators,the sex health disparities enlarged with increasing age.The period effect showed that the sex gaps of cognitive function enlarged from 1998 to 2018,and period effects on the sex gaps of the other health indicators were not significant.The cohort-based sex gaps of most indicators converged across successive cohorts.Residence-stratification health trends: After controlling for age,period and cohort effects,rural residents had better ADL while worse cognitive function and self-rated health than urban residents.No significant difference was found in physical function between rural and urban residents.The residence gaps of ADL enlarged with age,while the residence gaps of other indicators didn't change significantly with age.The period effects on the residence gaps were not significant.The cohort effects showed that the residence gaps of ADL converged across successive cohorts,while the cohort effects on the residence gaps of the other health indicators were not significant.Elderly health trajectories and related factors:ADL: There were three types of male trajectories: no-disability,starting low and rising gradually,and starting low and rising quickly.There were also three types of female trajectories: starting low and rising gradually,starting low and rising quickly,and starting high and rising quickly.Most females had more disability than their male counterparts at the same age.Mortality probability trajectories followed a hierarchy in consistence with ADL trajectories approximately.Elders lived in eastern region,had non-agricultural occupations and were born in urban areas were more likely to belong to less favorable trajectory groups.Cognitive function: There were four types of male trajectories: sharp,moderate,slow and slight decline.There were also four types of female trajectories: sharp,moderate,slow and progressive decline.The proportion of females in worse cognitive trajectory was higher than that of males.Most females had lower cognitive function than their male counterparts at the same age in corresponding group.For males,mortality probability trajectories followed a hierarchy in consistence with cognitive trajectories approximately.For females,after the age of 88,mortality probability trajectories followed a hierarchy in consistence with cognitive trajectories approximately.Illiteracies were less likely to belong to the most favorable trajectory group.Physical function: There were three types of trajectories for males and females: strating low and declining quickly,starting high and declining quickly,and starting high and declining gradually.The proportion of females in worse physical function trajectory was higher than that of males.Mortality probability trajectories followed a hierarchy in consistence with physical performance trajectories approximately.Elders lived in eastern region were more likely to belong to less favorable trajectory groups.Self-rated health: There were two types of male trajectories: starting low and rising,and starting high and remaining stable.There were also two types of female trajectories: starting low and rising,and starting high and rising.Mortality probability trajectories followed a hierarchy in consistence with self-rated health trajectories approximately.Elders lived in western and middle region were more likely to belong to the less favorable trajectory group.Conclusions(1)Age,period,and cohort had different and independent effects on the overall health trends of elders,as well as the the health trends of gender and residence stratification.Age effects were more pronounced than period and cohort effects.(2)As for overall health trends,most health indicators decreased with age in an increasing rate and remained stable with period and cohort.(3)The sex disparities in health enlarged with age.The sex gaps of cognitive function diverged with period,and period effects on the sex gaps of other health indicators were not significant.The cohort-based sex gaps mostly converged across successive cohorts.(4)The residence disaparites in ADL enlarged with age.The residence gaps of health indicators still existed with period.Across successive cohorts,the advantages of rural residents in ADL gradually disappeared,while the disadvantages of rural residents in cognitive function and self-rated health still existed.(5)The heterogeneity of elderly health trajectories was identified.The health trajectories of females were more unfavorable than males.Factors like region and education level were relative to the trajectory memberships.