What Does Elevated LDH Level In Blood Indicate?

Hello. My husband is a Hodgkins lymphoma survivor and an autologous bone marrow transplant recipient who has been in remission 5 years. Went for a regular check up last week and all blood work is stellar but elevated LDH 229, with max being 220. He is also on synthroid and baby aspirin. Is this an indicator something is going on? Please help! Thanks!