Final Report Summary - HEMOX (The male-female health-mortality paradox)
The main objective of the HEMOX project was to decisively advance the understanding of the so-called "gender and health paradox" - describing the phenomenon that women live longer than men but experience worse health - by demonstrating that the reverse relationship between gender on the one side, and health and mortality on the other, is not as paradoxical as it seems. We extended the state-of-the-art by introducing the "longevity hypothesis" which states the existence of a direct relationship between longevity and live years spent in poor health regarding less severe health dimensions, i.e. those health domains which are not closely associated with the risk of dying. Consequently, we hypothesized that women show higher morbidity rates than men for longstanding illnesses not because they are female, but because they are the sex with higher life expectancy.
We tested this hypothesis in a series of quasi-experimental settings in which we investigated the association between longevity and life years spent in poor health - measured by different health indicators with strong or weak relationships to mortality - across sub-populations with different levels of life expectancy and corresponding gender gaps. The initial tests were done with Catholic nuns and monks who show higher life expectancies than the general population. We collected data on the health of order members in two surveys conducted in 2012 and 2014. The surveys were based on self-administered questionnaires and include individuals aged 50 years and older. In total, 1,158 order members of 16 different orders from Germany and Austria participated to the first survey (response rate: 68.8 percent). Of those still alive in 2014, 936 filled and returned the questionnaire of the second survey wave (response rate: 86.2 percent). For the general populations of Germany and Austria we used data from the EU-SILC 2012 survey, restricted to ages 50 and above (n = 9,169). These data were used to estimate healthy and unhealthy life years for 30 sub-populations defined by different characteristics, e.g. education level, income, BMI and smoking status. Life tables for Catholic order members were based on the continuously extended nuns’ and monks’ mortality data base of the Cloister Study collected from order archives. Life tables for the other sub-populations were estimated with the specifically developed "Longitudinal Survival Method", using data from health surveys with mortality follow-up, national population statistics and the Human Mortality Database.
The results confirmed our hypothesis and revealed that the direction and the extent of gender differences in healthy life years are not universal but depend on the definition of health. A female disadvantage in healthy life years exists in particular among those health dimensions which are not (closely) related to mortality, such as chronic diseases. We found that this disadvantage of women is in fact mostly a direct consequence of their advantage in longevity. It reduces to a minimum when mortality differences between women and men are controlled for. The remaining disadvantages of women in healthy life years are eliminated when gender differences in health reporting are adjusted for. On the basis of these results we developed an explanation model for the "gender and health paradox", based on three central factors: (1) the definition of health, (2) the longevity effect, and (3) gender-specific health reporting behavior. This explanation model can serve as basis for new interdisciplinary follow-up research on gender differences in health and mortality and to advance the general understanding of the mechanisms behind healthy ageing.
We tested this hypothesis in a series of quasi-experimental settings in which we investigated the association between longevity and life years spent in poor health - measured by different health indicators with strong or weak relationships to mortality - across sub-populations with different levels of life expectancy and corresponding gender gaps. The initial tests were done with Catholic nuns and monks who show higher life expectancies than the general population. We collected data on the health of order members in two surveys conducted in 2012 and 2014. The surveys were based on self-administered questionnaires and include individuals aged 50 years and older. In total, 1,158 order members of 16 different orders from Germany and Austria participated to the first survey (response rate: 68.8 percent). Of those still alive in 2014, 936 filled and returned the questionnaire of the second survey wave (response rate: 86.2 percent). For the general populations of Germany and Austria we used data from the EU-SILC 2012 survey, restricted to ages 50 and above (n = 9,169). These data were used to estimate healthy and unhealthy life years for 30 sub-populations defined by different characteristics, e.g. education level, income, BMI and smoking status. Life tables for Catholic order members were based on the continuously extended nuns’ and monks’ mortality data base of the Cloister Study collected from order archives. Life tables for the other sub-populations were estimated with the specifically developed "Longitudinal Survival Method", using data from health surveys with mortality follow-up, national population statistics and the Human Mortality Database.
The results confirmed our hypothesis and revealed that the direction and the extent of gender differences in healthy life years are not universal but depend on the definition of health. A female disadvantage in healthy life years exists in particular among those health dimensions which are not (closely) related to mortality, such as chronic diseases. We found that this disadvantage of women is in fact mostly a direct consequence of their advantage in longevity. It reduces to a minimum when mortality differences between women and men are controlled for. The remaining disadvantages of women in healthy life years are eliminated when gender differences in health reporting are adjusted for. On the basis of these results we developed an explanation model for the "gender and health paradox", based on three central factors: (1) the definition of health, (2) the longevity effect, and (3) gender-specific health reporting behavior. This explanation model can serve as basis for new interdisciplinary follow-up research on gender differences in health and mortality and to advance the general understanding of the mechanisms behind healthy ageing.