Life Expectancy at Birth in Milwaukee County: A Zip Code-Level Analysis.

PURPOSE

Life expectancy at birth is used as a barometer of the health and well-being of a population. Life expectancies vary widely across Wisconsin counties. While much of the analysis of life expectancy in Wisconsin has focused on counties, there may be important differences in life expectancy within counties by zip code.

METHODS

To calculate life expectancy, death count data and population estimates were entered into an abridged life table using the Chiang methodology. Data were linked with measures from the American Community Survey to examine the relationship between life expectancy and zip code characteristics.

RESULTS

Life expectancy varies greatly across zip codes in Milwaukee County. Overall, there was a 12-year difference in the life expectancy of children born into zip codes with the lowest and highest life expectancy: 53206 (71.3 years) and 53217 (83.2 years). There was a strong positive correlation between life expectancy and median household income (r=0.784, P<0.0001), educational attainment of a bachelor's degree or higher (r=0.741, P<0.0001) and the socioeconomic index combining education and income (r=0.819, P<0.0001).

CONCLUSIONS

Disparities in life expectancy within Milwaukee County are stark and correlate with differences in social and economic factors. To improve health outcomes such as life expectancy, health care practitioners and health care systems must become more involved in activities at the social and policy levels to improve social and economic conditions that would allow their patients to live healthier and longer lives.