A recently published paper by CEPAR Chief Investigator Professor Philip Clarke and colleagues analyses how self-ratings of health are associated with mortality in different parts of the world, and finds this relationship varies across groups of countries.
Self-rated health is a measure that reflects a person’s perception of their own health. A common way to measure self-rated health is through asking people to rate their overall health on a scale. International studies often use the visual analogue scale (VAS) that provides a scale from 0 to 100 on which to rate health.
"While this has the advantage of using a numerical scale, it is unclear if people in different parts of the world with similar health status use this scale in the same way," said Professor Clarke.
"One way to compare self-reported health in different parts of the world is to compare how well it predicts individual chances of surviving over dying over the next few years."
CEPAR researchers did this using data from the ADVANCE study which involved over 11,000 people with type 2 diabetes across Asia, Eastern Europe and established market economies, such as Australia.
They found that lower self-rated health scores predict higher 10-year all-cause mortality for people with type 2 diabetes worldwide, but that this relationship varies across groups of countries.
“We were somewhat surprised by the results. While people with diabetes in Asia rate their health much higher there tends to be less variation in scores, but their responses are actually more sensitive in predicting mortality,” said Professor Clarke.
“To give an idea of the magnitude of differences across regions, we estimated the difference in a VAS scale that would be equivalent to knowing whether someone smokes in predicting five-year mortality.
“We found this is equivalent to a 10-point difference on the VAS scale in Asia compared with 15 points in developed countries and a 35-point difference in Eastern Europe.
“Our study shows the VAS score can be a useful global health measure in clinical practice for people with type 2 diabetes, but adjustment would be required before it can be directly compared across countries and regions,” he said.
X. Hua, T. W. C. Lung, M. Woodward, J. A. Salomon, P. Hamet, S. B. Harrap, G. Mancia, N. Poulter, J. Chalmers, P. M. Clarke: Self‐rated health scores predict mortality among people with type 2 diabetes differently across three different country groupings: findings from the ADVANCE and ADVANCE‐ON trials. Diabet. Med. 00, 1– 7 (2020).