Objectives: The aim of this study was to examine relationships between income and mortality, focusing on the predictive utility of single-year and multiyear measures of income, the shape of the income gradient in mortality, trends in this gradient over time, the impact of income change on mortality, and the joint effects of income and age, race, and sex on mortality risk.
Methods: Data were taken from the Panel Study of Income Dynamics for the years 1968 through 1989. Fourteen 10-year panels were constructed in which predictors were measured over the first 5 years and vital status over the subsequent 5 years. The panels were pooled and logistic regression was used in the analysis.
Results: Income level was a strong predictor of mortality, especially for persons under the age of 65 years. Persistent low income was particularly consequential for mortality. Income instability was also important among middle-income individuals. Single-year and multiyear income measures had comparable predictive power. All effects persisted after adjustment for education and initial health status.
Conclusions: The issues of low income and income instability should be addressed in population health policy.