Previous exposure to viruses such as: Epstein-Barr virus (the virus that causes mononucleosis)

Alterations to the immune system (HIV): more cases of HL have been found in HIV-positive patients who take intravenous drugs

Family history: patients with previous family history of HL (first-degree relatives). It is estimated that 4.5% of new diagnoses are attributable to family connections.

The appearance of the disease depends on age, and many cases have been reported in young people (15-30) and then in people over 55. It is more common in men, except in a certain type of lymphoma (nodular sclerosing HL) that is more common in women.