Mortality rate refers to the number of deaths within a specific population over a defined period, typically expressed per 1,000 individuals. Determining a single “group” with the highest mortality rate is complex, as “group” can encompass various classifications. These include age, specific causes of death, geographic location, and socioeconomic factors. This article examines how these diverse factors influence which groups experience the highest mortality rates.
Age as the Primary Factor
The oldest age groups consistently exhibit the highest mortality rates. Mortality is low during childhood, following infancy, and gradually increases through adulthood, rising sharply in later life. While infant mortality remains a concern, the volume of deaths among older adults due to natural processes positions them as the group with the highest mortality by age.
Aging contributes to increased mortality risk. Cellular senescence and the accumulation of molecular damage lead to a gradual decline in physical and mental capacities. Organ function deteriorates, making individuals more susceptible to disease and less able to repair bodily damage. This decline increases the risk of developing various diseases, including cancers and cardiovascular conditions, and vulnerability to infections. The mortality rate approximately doubles every six to seven years during adulthood, meaning an 80-year-old is about ten times more likely to die than a 60-year-old.
Leading Causes of Death
Beyond age, specific diseases and conditions influence mortality. Globally, ischemic heart disease is the leading cause of death, accounting for 13% of total deaths in 2021. Other global causes include COVID-19, stroke, various cancers, chronic obstructive pulmonary disease, and lower respiratory infections. These causes contribute to mortality across diverse populations, though their prevalence differs by age or region.
Noncommunicable diseases (NCDs) account for a substantial portion of deaths worldwide. In 2021, seven of the ten leading causes of death globally were NCDs, representing 38% of all deaths. In high-income countries, NCDs drive mortality rates, with ischemic heart disease and stroke consistently among the top causes. Deaths from Alzheimer’s disease and other dementias have also increased in these regions.
Socioeconomic and Demographic Disparities
Socioeconomic status, including income, education, and occupation, influences mortality rates within populations. Individuals with higher socioeconomic standing have improved access to healthcare and resources, correlating with lower mortality rates. Conversely, living in neighborhoods with low socioeconomic status links to a higher risk of premature death.
Disparities in access to quality healthcare, nutritious food, safe living environments, and educational opportunities contribute to elevated mortality rates in disadvantaged groups. These systemic factors increase susceptibility to chronic diseases. Demographic characteristics such as gender also play a role, with males experiencing higher mortality rates than females due to biological, behavioral, and environmental influences.
Global Variations in Mortality
Mortality rates vary considerably across countries and regions. These differences connect to a country’s economic development, healthcare infrastructure, public health initiatives, and access to resources like clean water and sanitation. For instance, an 18-year difference in life expectancy exists between high-income and low-income countries.
In low-income countries, communicable diseases, including infectious diseases and maternal and child health conditions, account for a larger proportion of deaths. In 2021, eight of the ten leading causes of death in low-income countries were communicable diseases. In contrast, non-communicable diseases are the predominant causes of death in high-income countries. While progress has reduced mortality in many low and middle-income nations, inequalities persist between and within regions.