Predictors of mortality: an international comparison of socio-demographic and health characteristics from six longitudinal studies on aging: the CLESA project.

Purpose: Multiple factors contribute to mortality in the elderly, but the extent to which traditional factors contribute independently to mortality in different countries is not known. Our objective is to determine the differential impact of socio-demographic variables, selected diseases, health habits and disability on all-cause mortality, among older people living in five European countries and Israel.

Methods: From six longitudinal studies on aging (TamELSA-Tampere (Finland), CALAS-Israel, ILSA-Italy, LASA-Netherlands, AL-Leganés (Spain), SATSA-Sweden), a harmonized common database was created in the context of the CLESA Project (Cross-national determinants of quality of life and health services for the elderly). A common five-year follow-up was used.

Results: The highest mortality rate was found in Tampere among females (98.7%) and in Israel among males (108.3%), whereas the lowest was observed in Leganés for males (72.3%) and in The Netherlands for females (44.6%). In multivariate models, some predictors were homogeneously, significantly distributed across the six countries, including older age (HR = 1.57) and male sex (HR = 1.60) among the socio-demographic variables; smoking status (HR = 1.15) and alcohol consumption (HR = 0.81) among the health habits variables; presence of heart disease (HR = 1.34), diabetes (HR = 1.46), cancer (HR = 1.93), respiratory disease (HR = 1.19), and disability (HR = 2.92) among the health status variables. Marital status, education, and drug use did not have homogeneous effects in the six countries.

Discussion: This large international study shows that multiple factors contribute to increased risk of all cause mortality among older people and that most risk factors are similar across countries. Disability, age greater than 80 years, cancer and male sex were identified as the strongest common risk factors of mortality.