Updated June 2007- According to a study completed in Hong Kong, elderly obese people have a lower risk of contracting tuberculosis in comparison to underweight and average weight elderly people.
The study had 42,116 people from 18 geriatric centers closely monitored for 5 years from 2000. The participants had to be 65 or older, and were put into categories depending on their body mass index (BMI).
People who were underweight were found to be six times more likely to be infected with TB than an overweight person. Average weight participants were three times more likely to contract TB than the obese. The findings illustrate that the heavier a person is, the lower their risk for TB.
Researchers from the study think it is important that more studies be done to find the reason for these findings. Some researchers believe that food availability has had a direct effect on falling TB rates. In the late 18th and early 19th century food was much more available and TB rates started declining.
Whatever the reasoning, these conclusions can be very useful to people in places with scarce resources. BMI could be used as a deciding factor for whether people should be screened or treated for tuberculosis.