Wednesday, January 29, 2014

Physical Stature Decline and the Health Status of the Elderly Population in England

Physical Stature Decline and the Health Status of the Elderly Population in England

Economics and Human Biology, Forthcoming

Alan Fernihough,Institute for International Integration Studies, Trinity College Dublin
Mark E. McGovern, Harvard Center for Population and Development Studies

Abstract

Few research papers in economics have examined the extent, causes or consequences of physical stature decline in aging populations. Using repeated observations on objectively measured data from the English Longitudinal Study of Ageing (ELSA), we document that reduction in height is an important phenomenon among respondents aged 50 and over. On average, physical stature decline occurs at an annual rate of between 0.08% and 0.10% for males, and 0.12% and 0.14% for females—which approximately translates into a 2cm to 4cm reduction in height over the life course. Since height is commonly used as a measure of long-run health, our results demonstrate that failing to take age-related height loss into account substantially overstates the health advantage of younger birth cohorts relative to their older counterparts. We also show that there is an absence of consistent predictors of physical stature decline at the individual level. However, we demonstrate how deteriorating health and reductions in height occur simultaneously. We document that declines in muscle mass and bone density are likely to be the mechanism through which these effects are operating. If this physical stature decline is determined by deteriorating health in adulthood, the coefficient on measured height when used as an input in a typical empirical health production function will be affected by reverse causality. While our analysis details the inherent difficulties associated with measuring height in older populations, we do not find that significant bias arises in typical empirical health production functions from the use of height which has not been adjusted for physical stature decline. Therefore, our results validate the use of height among the population aged over 50.

JEL classification: I10; I12; J11

Keywords: Height; Physical Stature Decline; Early Life Conditions; Health; Aging

Highlights:

Physical stature decline results in a 2–4 cm reduction in height over the life course, relative to maximum height.

Comparisons of average height across cohorts comprising individuals over 50 must adjust for age structure to be valid.

Deteriorating health and stature loss occur simultaneously.

For women, physical stature decline and health are likely to be associated via reductions in muscle mass and bone density.

We validate the inclusion of height which has not been adjusted for stature loss in health production function models.

http://ideas.repec.org/p/gdm/wpaper/11214.html

2 comments:

Liam Delaney said...

Well done guys! I have to admit shrinking has been the bane of a number of my research projects so its good to see work like this quantifying it properly.

Mark McGovern said...

Thanks Liam, good to settle this old debate.