Stress and rheumatoid arthritis are linked in a vicious cycle: RA causes stress, and stress can worsen RA. Constant pain, fatigue, and poor sleep create a dangerous cycle.
People affected by stress-related problems , such as post-traumatic stress disorder (PTSD) , acute stress reaction, and adjustment disorder, may be at higher risk of rheumatoid arthritis.
PTSD  can be caused by a combination of intense traumatic experiences, it may be physical, sexual, or emotional abuse, domestic violence, war experiences, assault, major accident, life-threatening occurrences, and how your brain reacts to the chemicals and hormones your body releases in reaction to stressful events.
Vitamin D Deficiency
Too little of this vital nutrient can lead to having RA. Increasing vitamin D consumption has been shown to help with rheumatoid arthritis. Vitamin D helps the body absorb calcium, which is essential for building strong bones. Reduced vitamin D intake has been linked to increased susceptibility to the development of RA, and its deficiency is associated with disease activity in patients with RA.
Research has found that vitamin D may play a significant role in joint health and that low levels may increase the risk of RA.