What causes rheumatoid arthritis?
The cause of rheumatoid arthritis remains unknown, but researchers believe it is triggered by a combination of genetic and environmental factors. There is a strong link between rheumatoid arthritis and the aging process, and rheumatoid arthritis is more common in female and overweight people.
So, instead of causes, we usually talk about risk factors, which make you more likely to have rheumatoid arthritis if you have them but do not constitute a direct trigger of the disease. The most important risk factors include:
- Age: The likelihood of having rheumatoid arthritis increases with age, especially if you have other risk factors on this list.
- Sex: In most cases, rheumatoid arthritis will be more common in women than in men. The prevalence is two or three times higher in females.
- Genetics: There are a group of genes called HLA (human leukocyte antigen) class II genotypes which are involved in the development of rheumatoid arthritis. Patients with these genes usually experience more severe symptoms. However, it is also known that these genes can stay silent, and they are only triggered when combined with environmental elements such as smoking.
- Smoking: This habit triggers and worsens inflammation in rheumatoid arthritis and has been identified as an environmental factor that triggers the disease in susceptible people.
- Not giving birth: Female patients who never gave birth are more likely to experience rheumatoid arthritis later in life. Breastfeeding is considered a protective factor because it reduces the chance of having rheumatoid arthritis.
- Obesity: Like smoking, being obese increases inflammation in the organism because the fatty cell tissue produces inflammatory cytokines. Thus, it is another factor that triggers susceptible people to develop this disease.