Lifestyle and excess mortality during the COVID-19 pandemic

Results
During the COVID-19 pandemic more people have died than would be expected based on historical mortality rates. Statistics Netherlands estimates that the total excess mortality in 2020 and 2021 amounts to 30 thousand people. This study focuses on whether excess mortality is higher among people with an unhealthy lifestyle.

Excess mortality is higher among people with unfavorable lifestyle factors. About half of the Dutch population is overweight, but within this group between 70 and 98 percent of excess mortality occurs. The difference is also significant for people with a history of smoking or a combination of these two lifestyle factors, and for people who are lonely. For people who drink excessively, the difference is not statistically significant.

For overweight, whether or not combined with a history of smoking or too little exercise, there is also a difference in excess mortality within breakdowns by population groups based on sex, age, origin, education level and perceived health. Within the group of people with poor perceived health, excess mortality among overweight people appears to be particularly high – possibly because of comorbidities. For other lifestyle factors, the picture is less robust.

COVID-19 appears to be the determining cause of additional excess mortality. During the excess mortality periods, all-cause mortality among overweight people increases compared to those without overweight. However, this effect disappears when mortality due to COVID-19 is excluded. Similar results are found for other lifestyle factors.

Method
These figures are based on a comparison of developments in mortality before and during the COVID-19 pandemic between people who meet a certain lifestyle factor and those who do not. In the period from January 2018 to February 2020, mortality for these groups follows a similar trend. However, in the period from March 2020 to December 2022, mortality increases more for people with unhealthy lifestyles than for people with healthy lifestyles. We interpret this additional increase in mortality as excess mortality.