Why women live longer than men?


For more than a century, women in the United States have lived longer than men. Demographers largely attribute this well-known statistical gap to behavioral differences between men and women in areas such as smoking and drinking habits, injury risk and drug use. The overall lifespan of Americans has been slowly increasing for decades. However, data from the U.S. Centers for Disease Control and Prevention (CDC) shows that this trend is reversed among men.

In 2010, women's life expectancy was 4.8 years longer than men's. By 2021, this gap has grown to 5.8 years, which is also the highest value since 1996. In the 20th century, heart disease was the leading cause of the difference in life expectancy between men and women. But in a report recently published in JAMA Internal Medicine, researchers' latest analysis of CDC data shows that COVID-19 infections and an increasing number of drug overdoses are the leading causes of death among men. The culprit with higher rates.

Philip Cohen, a professor of sociology at the University of Maryland, who was not involved in this study, said that factors such as the higher medical burden of COVID-19 complications, differences in health behaviors, and employment in high-risk industries have all contributed to the decline in men’s employment in high-risk industries. The higher mortality rate during the COVID-19 pandemic is also an important reason for the decline in life expectancy and the widening of the gender gap. "This study highlights some of the underlying public health issues that impact male life expectancy, particularly drug overdoses, suicide and other acts of violence."

Between 2010 and 2019, before the COVID-19 pandemic, the biggest contributor to the gender gap in life expectancy was unintentional injuries — primarily drug overdoses, but also related to traffic accidents such as car crashes. In addition, other factors include increased rates of diabetes, heart disease, suicide and homicide. Taken together, they add 0.23 years to the life expectancy gap.

The most significant change in life expectancy at birth occurred between 2019 and 2021, at the beginning of the COVID-19 pandemic. On the premise that the mortality rate caused by accidental injuries (mostly drug overdoses) was already high, the average life expectancy of men during this period dropped to 73.2 years, while the average life expectancy of women was 79.1 years.

The difference is "concerning," said study co-author Brandon Yan, a resident at the University of California, San Francisco School of Medicine and Harvard T.H. Chan School of Public Health and lead author of the new study. Since the outbreak of the new coronavirus, life expectancy in the United States has been declining, from 78.8 years in 2019 to 76.1 years in 2021. "The situation is not optimistic," Brandon said.

Initially, Brandon and his colleagues were surprised by the disproportionate mortality rate among men. "Part of the reason is that men generally have more severe symptoms of COVID-19 than women," he said.

Sarah Richardson, director of the Gender Science Laboratory at Harvard University and not involved in the new study, said the findings were consistent with her previous research showing that men have a slightly higher mortality rate from COVID-19 compared with women. . "So from that perspective, it's not that hard to understand," Richardson said. The trend is even more pronounced among younger people, she added.

Elizabeth Wrigley-Field, associate professor of sociology at the University of Minnesota, who was not involved in the new study, said premature death can magnify life expectancy calculations. As an example, she said, most people who die from opioid overdoses would have had decades to live. "That's why these types of deaths have a larger impact on the average life expectancy of a population," Wrigley-Field added. "It tends to have a larger impact than the causes of death in older people."

This gender gap is offset slightly by improvements in male cancer survival rates and worsening maternal mortality, a growing public health problem across the country. "This also has a profound impact on life expectancy," Wrigley-Field said. "Because these women died relatively young, and they would have lived for decades more."

Previous research on women's relative longevity has mostly focused on physiological factors, such as women's stronger immune systems. But Brandon believes this does not explain the significant change in life expectancy between 2010 and 2021. The changes that have occurred in such a short period of time should be attributed to increasing rates of chronic disease burden and worsening mental health crises among men.

Richardson said the extent to which men's mortality rates related to COVID-19 and drug overdoses have worsened is likely related to occupation and their ability to access health care. Society's standards and constraints on masculinity can also prevent men from seeking help when they are in pain or need care, she added. "Men are less likely to seek medical attention before their condition becomes more severe, which leads to poorer outcomes." Brandon believes factors such as being homeless or working in construction and agriculture, where men are overwhelmingly the majority, are associated with Related to the increase in COVID-19 infection rates.

Donald Miller, an epidemiologist at Boston University School of Public Health and a co-author of the new study, believes that getting more older men vaccinated may improve the gender gap in life expectancy. But he also mentioned: "The bigger challenge is to control mortality among young men." At present, we need more research to analyze the reasons behind men's risky health behaviors so that we can target behaviors such as drug abuse, violence and suicide. Develop better interventions. Cohen said preventive measures, pastoral care and early detection will help alleviate these problems.

This recent analysis used population death data to support this idea, but these data were not sufficiently disaggregated by sex. At the same time, Richardson believes the study also ignored influences such as geography, race or socioeconomic factors that might reveal large differences between subgroups. Her previous analysis of COVID-19 deaths showed that death rates vary widely across U.S. states. Now, Brandon is awaiting the release of 2022 life expectancy data at the end of this month. He hopes that this additional information will help them better study the demographic factors that may affect gender differences in the future.