Ruby Yu is a research assistant professor at the Chinese University of Hong Kong (CUHK), specialising in gerontology and geriatrics. She is also a research fellow at the CUHK Jockey Club Institute of Ageing. Her recent paper Trajectories of frailty among Chinese older people in Hong Kong between 2001 and 2012: An Age-period-cohort Analysis was published today in Age and Ageing journal.
There is no doubt that people from countries all over of the world are living longer, but there is little evidence to suggest that older people today are living healthier than their predecessors did at the same age. This is a major cause of concern for many governments around the world because if the added years of people today are dominated by chronic diseases and functional disabilities, there will be negative implications (e.g., extended treatment for older people which increases the health and social care cost to society).
Hong Kong, a special administrative region of China situated on the Southern coast, is no exception. It has topped the world charts for longevity, with men expected to live to 81.3 years, while women are expected to live to 87.3 years in 2016. However, are our older people today living healthier than their parents?
This study examined trajectories of the frailty index among over 90,000 community-dwelling population older than 65 years, using 12 waves (2001-2012) of data on multiple birth cohorts (cohort 1901-1923, cohort 1924-1929, cohort 1930-1935, cohort 1936-1941, and cohort 1942-1947) from the Elderly Health Centres of the Department of Health in Hong Kong. The frailty index is a proxy measure of ageing and vulnerability to poor outcomes.
Our findings suggested that more recent cohorts had higher levels of frailty than did earlier cohorts at the same age. Difference was also observed in both men and women. We also found that the cohort effects are independent of age, period, gender, marital status, education level, demographics, socioeconomic status, lifestyle and social factors.
Whenever we look at the trend, a question immediately springs to mind. Why are our older people today frailer? Unfortunately this analysis is not able to answer the question, but there seems to be many possible reasons. We speculated that the increase in chronic diseases and impaired physical and cognitive functioning, the higher proportion of sedentary occupations, the rising number of older people living alone associated with the adverse impacts on the social networks or connections of older people may have contributed to the increased levels of frailty over time.
Our findings have a negative implication that the gains in life expectancy are associated with concurrent increases in levels of frailty with the potential for greater associated costs for medical care, social services, and long-term care. Our findings are consistent with those published by Andrew Kingston and colleagues in The Lancet, which is highly relevant to this topic. Kingston and colleagues’ study compares two large British cohorts of older people aged 65 years or older interviewed in 1991 and 2011 and shows that while life expectancy increases, the number of years older people has spent with greater levels of dependency and substantial care needs also increases. Findings from our study as well as from the Kingston and colleagues’ study seem to substantiate the notion of the so-called “failure-of-success”, which suggested that increased longevity would result in an absolute decline in health.
Having said that, we can improve the situation using several methods, because frailty is reversible. Many studies have described the need to develop frailty interventions, coupled with early detection in primary care, to combat the increasing rates of frailty.