For public health officials who study life expectancy, learning that both minor and major differences exist among global populations may come as no surprise. However, a recent study’s revelation that drastic differences in life expectancy exist among Americans has caught even experienced researchers off guard.
Learn what this 24-year study reveals about the life expectancy of Americans and discover what public health experts can learn from this data.
How Researchers Designed This Longevity Study
Researchers have long observed that people who live in certain parts of the country live several years longer than others. To better understand why this happens, whether it is increasing or decreasing, and which factors may contribute to differences in longevity, a group of researchers designed a comprehensive study.
As JAMA Internal Medicine explains, researchers created tables that tracked populations at the county level across the United States from 1980 to 2014. To do this, they used a combination of death records from the National Center for Health Statistics (NCHS), along with population records from the NCHS, the U.S. Census Bureau, and the Human Mortality Database.
With this information in hand, researchers determined the average life expectancy at birth and age-specific mortality risk in counties across the nation. Researchers incorporated factors such as race, ethnicity, socioeconomic status, metabolic risk, and access to health care into their conclusions.
What This Study Reveals About Life Expectancy
After analyzing the data and calculating the results, Jama Internal Medicine reports that the researchers determined that in 2014, the average life expectancy for both male and female Americans is 79.1 years. While life expectancy increased by an average of about five years across the nation, this measure is remarkably inconsistent from county to county, with a 20-year difference among various locations in the U.S.
As the Washington Post reports, those who enjoy the highest life expectancy in the U.S. dwell in the mountains of central Colorado, where many live an average of more than 85 years. In other areas, such as southwestern South Dakota, the average person lives just 67 years.
According to NPR, the life expectancy gap among U.S. counties echoes the differences between longevity in low- and high-income parts of the world. Socioeconomic status does appear to factor into the 20-year life expectancy gap revealed in this study of the U.S. Residents of areas with a high life expectancy, such as Summit County, Colorado, are some of the most well-off and highly educated in the nation. In contrast, residents of areas with a low life expectancy, such as Oglala Lakota County, South Dakota, or parts of southern Mississippi and eastern Kentucky are much poorer and have less education.
As Jama Internal Medicine explains, this study asserts that socioeconomic and race or ethnicity factors account for 60 percent of the variation in life expectancy among counties. Behavioral and metabolic risk factors account for 74 percent, and access to health care accounts for 27 percent of the difference in longevity.
In addition, the study reveals that geographic differences in the risk of death decreased among children and teenagers from 1980 to 2014, but this factor increased among older adults during the same time period. In fact, the gap between low and high life expectancy has increased by about two years over 34 years. This means the inequality in life expectancy actually increased during the 34 years that this study covered, and the longevity gap could continue to increase rather than even out over time.
What Public Health Officials Can Learn From This Study
While the study reveals numerous issues, many see it as a call to action. In fact, public health professionals may be able to implement targeted actions and policies to help close the gap.
For instance, as NPR reports, smoking and obesity have likely contributed significantly to lowering life expectancy in some of the hardest-hit areas. While many communities around the nation have responded to public health issues like these with anti-smoking and anti-obesity initiatives, others, such as those in southwestern South Dakota, have made little progress toward eradicating these issues in 34 years.
Along the same lines, other public health researchers have surmised that young adults facing worse economic prospects than their parents did have made choices that lower their life expectancy in certain parts of the country. For instance, choosing low-quality, unhealthy food that contributes to obesity may be more acceptable in counties plagued with lower than average incomes. Ultimately, the proliferation of obesity, smoking, and so-called “diseases of despair” may lead to lower life expectancy.
Public health experts may take a closer look at some counties in which life expectancy experienced the greatest increase during the 34-year study. For instance, some counties in Northern Virginia and central Alaska experienced double-digit increases in life expectancy.
Officials in the U.S. may also be able to use other nations’ policies as models. As the Washington Post explains, policymakers in Australia have long since established methods for eliminating smoking and obesity. Encouraging physical activity, improving access to healthy food choices, and limiting the ability to smoke all help to curb these risk factors.
While the full results of these policies remain to be seen in Australia, implementing similar procedures in the U.S. could have important implications. For instance, since life expectancy in the U.S. is actually on a slight downward trend, the nation as a whole is slowly becoming less productive and less competitive on an international scale. Improving life expectancy through forward-thinking public health policies could improve quality of life, productivity, and competition, ultimately addressing socioeconomic issues at the same time.
As a professional working in the public health field, you will likely focus on improving health in varied communities and positively impacting life expectancy. If you are interested in working on important issues like this, learn more about the MPH degree program at the Keck School of Medicine. An advanced degree could enable you to pursue a rewarding career in public health.