- Email: [email protected]
Ageing and health
Correspondence
According to Kaare Christensen and colleagues (Oct 3, p 1196),1 if the future pace of improvement in life expectancy in developed nations is comparable to that of the past two centuries, half of babies born in these countries since 2000 will live to 100 years. They provide neither empirical evidence nor specific projection scenarios to support this extreme assertion. Consider that published period life tables for Japanese women, the longest-lived population in the world, indicate that only 4·6% of the cohort born in 2000 are expected to live to 100 years.2 In the USA, this expectation is 2·0%. In other words, the 50% survival assertion by Christensen and colleagues is 11 times and 25 times greater than estimates for Japan or the USA, respectively, for the year 2000—implying that period mortality underestimates cohort life expectancy by decades. The data presented in table 1 are presented as though they come from observed life tables rather than from an unspecified set of projection assumptions. Figure 1 of the paper is no less misleading. Extrapolating “best practice” life expectancy into the future and claiming that most babies born today will live to 100 years is equivalent to marvelling at new world records for the 100 m run and then proclaiming that the rest of us will soon run that fast. Christensen and colleagues state that life expectancy is lengthening almost linearly in most developed countries, with no signs of deceleration. On the contrary, in England and Wales, Germany, the Netherlands, and the USA, life expectancy at age 65 years for women has converged to about 19·5 years, and has stagnated at that level in the USA and the Netherlands for most of the past 20 years.3 Christensen and colleagues also suggest that ageing processes are modifiable, and that recent increases in life expectancy are attributable www.thelancet.com Vol 375 January 2, 2010
to decelerated biological ageing. Although there is hope that this process is possible,4 no scientific evidence has yet shown that it can be achieved in human beings.5 We declare that we have no conflicts of interest.
*S Jay Olshansky, Bruce A Carnes [email protected] Department of Epidemiology and Biostatistics, University of Illinois at Chicago, Chicago, IL 60612, USA; and Oklahoma Health Sciences Center, Oklahoma City, OK, USA 1
2 3
4
5
Christensen K, Doblhammer G, Rau R, Vaupel JW. Ageing populations: the challenges ahead. Lancet 2009; 374: 1196–208. The Human Mortality Database. http://www. mortality.org/ (accessed Oct 7, 2009). Olshansky SJ, Carnes BA, Mandell MS. Future trends in human longevity: implications for investments, pensions and the global economy. Pensions 2009; 14: 149–63. Miller RA. “Dividends” from research on aging—can biogerontologists, at long last, find something useful to do? J Gerontol 2009; 64: 157–60. Sierra F, Hadley E, Suzman R, Hodes R. Prospects for life span extension. Annu Rev Med 2009; 60: 457–69.
I fully agree with Kaare Christensen and colleagues1 that ageing populations pose a great challenge for health care in the future. However, Christensen and colleagues discuss only limitations on physical function and disability among ageing populations. One should not forget that psychosocial factors (depressed mood, loneliness, fear, cognitive ability, social support) also need to be considered because they often have a negative effect on a person’s ability to manage daily life.2–5 Psychosocial problems can lead to other health complaints, both physical and psychological (such as depression, sleep disorders, higher blood pressure, immune stress responses, and worse cognition), just as physical functional limitations and various diseases can lead to psychosocial complaints (eg, feelings of vulnerability, depression, and loneliness).3–5 Thus, psychosocial variables must be considered together with physical health problems if we are to meet the increasing health-care demands of older people in the future. I declare that I have no conflicts of interest.
Ulf Jakobsson [email protected] Centre for Primary Health Care Research, Faculty of Medicine, Lund University, PO Box 157, SE-221 00 Lund, Sweden 1
2
3
4
5
Christensen K, Doblhammer G, Rau R, Vaupel JW. Ageing populations: the challenges ahead. Lancet 2009; 374: 1196–208. Jakobsson U, Hallberg IR. Loneliness, fear and quality of life among elderly in Sweden—a gender perspective. Aging Clin Exp Res 2005; 17: 494–501. Jakobsson U, Klevsgård R, Westergren A, Hallberg IR. Old people in pain: a comparative study. J Pain Symptom Manage 2003; 26: 625–36. Luanaigh CO, Lawlor BA. Loneliness and the health of older people. Int J Geriatr Psychiatry 2008; 23: 1213–21. Ayis S, Gooberman-Hill R, Ebrahim S. Long-standing and limiting longstanding illness in older people: associations with chronic diseases, psychosocial and environmental factors. Age Ageing 2003; 32: 265–72.
The Review by Kaare Christensen and colleagues1 presents a global trend of improvements in physical function in older populations. However, we should not be optimistic, considering the current status of younger generations. Annual national surveys in Japan, home to one of the longest-living populations in the world, show that physical functions such as walking and flexibility in people older than 65 years have indeed increased in this decade, in stark contrast to the gradually declining physical abilities of the younger generation (aged 6–19 years) from the peak in the 1970s. Similar trends in children and adolescents have been noted in Belgium2 and the USA,3 suggesting that it is a common phenomenon in many countries. It is not heretical to assume that the declining physical abilities of younger generations forecast a forthcoming reduction in physical functions of older people. Childhood obesity, a global health issue, is another indicator of an upcoming increase in populations with disability. Childhood obesity is closely associated with adulthood obesity, which predicts increased disability in later life.4 Furthermore, obesity in youth may be directly linked with earlier onset of disability.5
Photolibrary
Ageing and health
Submissions should be made via our electronic submission system at http://ees.elsevier.com/ thelancet/
25
According to Kaare Christensen and colleagues (Oct 3, p 1196),1 if the future pace of improvement in life expectancy in developed nations is comparable to that of the past two centuries, half of babies born in these countries since 2000 will live to 100 years. They provide neither empirical evidence nor specific projection scenarios to support this extreme assertion. Consider that published period life tables for Japanese women, the longest-lived population in the world, indicate that only 4·6% of the cohort born in 2000 are expected to live to 100 years.2 In the USA, this expectation is 2·0%. In other words, the 50% survival assertion by Christensen and colleagues is 11 times and 25 times greater than estimates for Japan or the USA, respectively, for the year 2000—implying that period mortality underestimates cohort life expectancy by decades. The data presented in table 1 are presented as though they come from observed life tables rather than from an unspecified set of projection assumptions. Figure 1 of the paper is no less misleading. Extrapolating “best practice” life expectancy into the future and claiming that most babies born today will live to 100 years is equivalent to marvelling at new world records for the 100 m run and then proclaiming that the rest of us will soon run that fast. Christensen and colleagues state that life expectancy is lengthening almost linearly in most developed countries, with no signs of deceleration. On the contrary, in England and Wales, Germany, the Netherlands, and the USA, life expectancy at age 65 years for women has converged to about 19·5 years, and has stagnated at that level in the USA and the Netherlands for most of the past 20 years.3 Christensen and colleagues also suggest that ageing processes are modifiable, and that recent increases in life expectancy are attributable www.thelancet.com Vol 375 January 2, 2010
to decelerated biological ageing. Although there is hope that this process is possible,4 no scientific evidence has yet shown that it can be achieved in human beings.5 We declare that we have no conflicts of interest.
*S Jay Olshansky, Bruce A Carnes [email protected] Department of Epidemiology and Biostatistics, University of Illinois at Chicago, Chicago, IL 60612, USA; and Oklahoma Health Sciences Center, Oklahoma City, OK, USA 1
2 3
4
5
Christensen K, Doblhammer G, Rau R, Vaupel JW. Ageing populations: the challenges ahead. Lancet 2009; 374: 1196–208. The Human Mortality Database. http://www. mortality.org/ (accessed Oct 7, 2009). Olshansky SJ, Carnes BA, Mandell MS. Future trends in human longevity: implications for investments, pensions and the global economy. Pensions 2009; 14: 149–63. Miller RA. “Dividends” from research on aging—can biogerontologists, at long last, find something useful to do? J Gerontol 2009; 64: 157–60. Sierra F, Hadley E, Suzman R, Hodes R. Prospects for life span extension. Annu Rev Med 2009; 60: 457–69.
I fully agree with Kaare Christensen and colleagues1 that ageing populations pose a great challenge for health care in the future. However, Christensen and colleagues discuss only limitations on physical function and disability among ageing populations. One should not forget that psychosocial factors (depressed mood, loneliness, fear, cognitive ability, social support) also need to be considered because they often have a negative effect on a person’s ability to manage daily life.2–5 Psychosocial problems can lead to other health complaints, both physical and psychological (such as depression, sleep disorders, higher blood pressure, immune stress responses, and worse cognition), just as physical functional limitations and various diseases can lead to psychosocial complaints (eg, feelings of vulnerability, depression, and loneliness).3–5 Thus, psychosocial variables must be considered together with physical health problems if we are to meet the increasing health-care demands of older people in the future. I declare that I have no conflicts of interest.
Ulf Jakobsson [email protected] Centre for Primary Health Care Research, Faculty of Medicine, Lund University, PO Box 157, SE-221 00 Lund, Sweden 1
2
3
4
5
Christensen K, Doblhammer G, Rau R, Vaupel JW. Ageing populations: the challenges ahead. Lancet 2009; 374: 1196–208. Jakobsson U, Hallberg IR. Loneliness, fear and quality of life among elderly in Sweden—a gender perspective. Aging Clin Exp Res 2005; 17: 494–501. Jakobsson U, Klevsgård R, Westergren A, Hallberg IR. Old people in pain: a comparative study. J Pain Symptom Manage 2003; 26: 625–36. Luanaigh CO, Lawlor BA. Loneliness and the health of older people. Int J Geriatr Psychiatry 2008; 23: 1213–21. Ayis S, Gooberman-Hill R, Ebrahim S. Long-standing and limiting longstanding illness in older people: associations with chronic diseases, psychosocial and environmental factors. Age Ageing 2003; 32: 265–72.
The Review by Kaare Christensen and colleagues1 presents a global trend of improvements in physical function in older populations. However, we should not be optimistic, considering the current status of younger generations. Annual national surveys in Japan, home to one of the longest-living populations in the world, show that physical functions such as walking and flexibility in people older than 65 years have indeed increased in this decade, in stark contrast to the gradually declining physical abilities of the younger generation (aged 6–19 years) from the peak in the 1970s. Similar trends in children and adolescents have been noted in Belgium2 and the USA,3 suggesting that it is a common phenomenon in many countries. It is not heretical to assume that the declining physical abilities of younger generations forecast a forthcoming reduction in physical functions of older people. Childhood obesity, a global health issue, is another indicator of an upcoming increase in populations with disability. Childhood obesity is closely associated with adulthood obesity, which predicts increased disability in later life.4 Furthermore, obesity in youth may be directly linked with earlier onset of disability.5
Photolibrary
Ageing and health
Submissions should be made via our electronic submission system at http://ees.elsevier.com/ thelancet/
25