Autoimmune conditions and primary central nervous system lymphoma risk among older adults.

Primary central nervous system lymphoma (PCNSL) risk is highly increased in immunosuppressed individuals, such as those with human immunodeficiency virus infection and solid organ transplant recipients, but rates are increasing among immunocompetent older adults (age ≥65 years). We utilized data from a large, nationally-representative cohort of older adults in the United States and found that PCNSL is significantly associated with systemic lupus erythematosus, polyarteritis nodusa, autoimmune hepatitis, myasthenia gravis and uveitis. Immunosuppressive drugs given to treat these conditions may increase PCNSL risk, but these associations cannot explain the observed temporal increase in PCNSL rates, given the low prevalence of these conditions.