Obesity, smoking, alcohol consumption and years lived with disability: A Sullivan life table approach

Background: To avoid strong declines in the quality of life due to population ageing, and to ensure sustainability of the health care system, reductions in the burden of disability among elderly populations are urgently needed. Life style interventions may help to reduce the years lived with one or more disabilities, but it is not fully understood which life style factor has the largest potential for such reductions. Therefore, the primary aim of this paper is to compare the effect of BMI, smoking and alcohol consumption on life expectancy with disability, using the Sullivan life table method. A secondary aim is to assess potential improvement of the Sullivan method by using information on the association of disability with time to death. Methods. Data from the Dutch Permanent Survey of the Living Situation (POLS) 1997-1999 with mortality follow-up until 2006 (n = 6,446) were used. Using estimated relative mortality risks by risk factor exposure, separate life tables were constructed for groups defined in terms of BMI, smoking status and alcohol consumption. Logistic regression models were fitted to predict the prevalence of ADL and mobility disabilities in relationship to age and risk factor exposure. Using the Sullivan method, predicted age-specific prevalence rates were included in the life table to calculate years lived with disability at age 55. In further analysis we assessed whether adding information on time to death in both the regression models and the life table estimates would lead to substantive changes in the results. Results: Life expectancy at age 55 differed by 1.4 years among groups defined in terms of BMI, 4.0 years by smoking status, and 3.0 years by alcohol consumption. Years lived with disability differed by 2.8 years according to BMI, 0.2 years by smoking and 1.6 by alcohol consumption. Obese persons could expect to live more years with disability (5.9 years) than smokers (3.8 years) and drinkers (3.1 years). Employing information on time to death led to lower estimates of years lived with disability, and to smaller differences in these years according to BMI (2.1 years), alcohol (1.2 years), and smoking (0.1 years). Conclusions: Compared with smoking and drinking alcohol, obesity is most strongly associated with an increased risk of spending many years of life with disability. Although employing information on the relation of disability with time to death improves the precision of Sullivan life table estimates, the relative importance of risk factors remained unchanged

Decomposition of educational differences in life expectancy by age and causes of death among South Korean adults

BACKGROUND: Decomposition of socioeconomic inequalities in life expectancy by ages and causes allow us to better understand the nature of socioeconomic mortality inequalities and to suggest priority areas for policy and intervention. This study aimed to quantify age- and cause-specific contributions to socioeconomic differences in life expectancy at age 25 by educational level among South Korean adult men and women. METHODS: We used National Death Registration records in 2005 (129,940 men and 106,188 women) and national census data in 2005 (15, 215, 523 men and 16,077,137 women aged 25 and over). Educational attainment as the indicator of socioeconomic position was categorized into elementary school graduation or less, middle or high school graduation, and college graduation or higher. Differences in life expectancy at age 25 by educational level were estimated by age- and cause-specific mortality differences using Arriaga’s decomposition method. RESULTS: Differences in life expectancy at age 25 between college or higher education and elementary or less education were 16.23 years in men and 7.69 years in women. Young adult groups aged 35–49 in men and aged 25–39 in women contributed substantially to the differences between college or higher education and elementary or less education in life expectancy. Suicide and liver disease were the most important causes of death contributing to the differences in life expectancy in young adult groups. For older age groups, cerebrovascular disease and lung cancer were important to explain educational differential in life expectancy at 25–29 between college or higher education and middle or higher education. CONCLUSIONS: The contribution of the causes of death to socioeconomic inequality in life expectancy at age 25 in South Korea varied by age groups and differed by educational comparisons. The age specific contributions for different causes of death to life expectancy inequalities by educational attainment should be taken into account in establishing effective policy strategies to reduce socioeconomic inequalities in life expectancy