Zimbabwe Tuberculosis Diagnoses Shifted to Older Ages Over 25 Years

The average age at which people in Zimbabwe were diagnosed with tuberculosis increased substantially between 2000 and 2024, according to a pooled analysis of 12 studies involving 15,925 patients.

Researchers from Bristol Medical School, working through The Health Research Unit in Zimbabwe, examined how the age profile of tuberculosis diagnoses changed over a 25-year period. The analysis was published in The Lancet Regional Health—Africa.

In 2000, the average age at diagnosis was 33.9 years for males and 28.9 years for females. By 2024, those figures had risen to 41.3 years for males and 40.4 years for females. The increase was therefore larger among females, whose average age at diagnosis rose by 11.5 years, compared with a 7.4-year increase among males.

Tuberculosis has historically been regarded as a disease affecting younger people. The researchers said the findings indicate that people diagnosed with tuberculosis in Zimbabwe are now older on average, as life expectancy increases and older adults more commonly live with conditions such as diabetes and heart disease that can increase tuberculosis risk.

Age can also affect how tuberculosis presents and is managed. According to the researchers, older adults may experience different symptoms and more treatment side effects. Treatment may also need to be managed alongside age-associated conditions, including diabetes and kidney disease, as well as frailty and sarcopenia—the loss of muscle strength and mass.

Professor Celia Gregson, co-director of The Health Research Unit in Zimbabwe, said the changing age pattern makes tuberculosis management more complex and argued that local and global diagnosis and treatment strategies should account for the needs of older adults.

The findings do not establish that aging itself caused the shift in diagnosis age. They describe a trend identified by modeling data pooled from the 12 underlying studies. The researchers said similar analyses should be conducted in other African countries where tuberculosis remains common to determine whether the same pattern is present elsewhere.

They also called for more detailed age reporting in annual tuberculosis data collected by the World Health Organization, saying this would make changes in the age at diagnosis easier to monitor. The researchers further indicated that treatment guidelines may need updating to address age-related factors in tuberculosis care.