Levels of testosterone that are low in men may predict a future development of rheumatoid arthritis.
The finding was published in the journal Annals of the Rheumatic Diseases and was based on research from the Swedish Malmo Preventive Medicine Program (MPMP), which started in 1974 and followed over 33,000 people born between 1921 and 1949.
Sex hormones have an influence in the development of rheumatoid arthritis. Historically, men and women who suffer from this health condition are liable to have low levels of testosterone in their blood. However, it is not confirmed that this is a contributory factor or a result of the disease.
As part of the MPMP, participants underwent several tests: they took surveys on lifestyle and health factors and had blood taken after an overnight fast.
The researchers pinpointed all subjects who were later diagnosed with rheumatoid arthritis up to December 2004 by reviewing national and regional databases.
The collected blood samples were available for 104 men who were later diagnosed with rheumatoid arthritis, and for 174 men of the same age who did not later have rheumatoid arthritis .
The time that passed, on average, between giving the blood sample and a diagnosis of rheumatoid arthritis, was about 13 years – however, it ranged from one to 28 years.
Rheumatoid factor is an antibody that predicts disease severity and is used as a tool to distinguish a level of the condition.
The factor status was seen at diagnosis for 83 of the men – close to three out of four (73%) of those participants tested positive for it; the remaining men tested negative.
The authors accounted for body mass index and smoking – both factors that can impact rheumatoid arthritis risk – and found that men with lower levels of testosterone in the blood were more inclined to develop the disease.
This was statistically significant for those who had tested negative for rheumatoid factor when they were diagnosed.
Additionally, these men had high levels of follicle stimulating hormone – a chemical that influences sexual maturity and reproduction – before their rheumatoid arthritis diagnosis. The authors believe this is an after effect of decreased testosterone production.
The outcomes encouraged the researchers to suggest that hormonal alterations come just before the onset of rheumatoid arthritis and directly impact disease severity.
These findings support previous studies which prove that testosterone may hinder the immune system. Rheumatoid arthritis is also more likely to go into remission at a starting stage in men, the authors conclude.
Other lifestyle factors have been found to increase rheumatoid arthritis risk, including:
A recent study, also published in the journal Annals of the Rheumatic Diseases, suggested that regular sun exposure can reduce the risk of rheumatoid arthritis in women.
Written by Kelly Fitzgerald