People with autoimmune disease such as lupus and rheumatoid arthritis (RA) are more likely to get dangerous blood clots during hospital stays. In fact, one 2014 Arthritis Research & Therapy meta-analysis of 25 studies found that people with inflammatory rheumatic diseases were three times more likely to experience venous thromboembolisms (VTEs, or blood clots in the veins) than the general population.
Lupus patients are four times more likely than people without an autoimmune disease to develop blood clots when hospitalized. And RA patients are one-and-a-half times more likely to develop blood clots during a hospital stay. According to a 2011 study from researchers in the United Kingdom, anyone with an immune-related disorder faces some sort of increased risk.