May 18, 2004 -- Two diseases that frequently strike young, affluent adults may share similar causes. A new study shows that multiple sclerosis (MS) and Hodgkin's lymphoma tend to run in families and provides new evidence to support the notion that the two diseases may have a common origin.
Researchers say the diseases share many characteristics, which have prompted many to suspect that they may have a common environmental or physical cause. For example, both emerge in young adulthood, have been associated with socioeconomic affluence, and tend to cluster within families.
Multiple sclerosis is an autoimmune disorder that affects the nervous system and causes loss of muscle control. Hodgkin's lymphoma is a type of cancer that develops in a type of white blood cell within the lymph nodes and affects the ability of the immune system to provide protection against infection. It causes swelling of the nodes and pain.
Diseases May Share Common Cause
In this study, researchers looked at whether people with multiple sclerosis and their families are at higher risk of Hodgkin's lymphoma and vice versa. Danish researchers looked at population registers to find people with the conditions and their close relatives.
They found nearly 12,000 people with multiple sclerosis and 20,000 of their first-degree relatives (parent, sibling, or child). They also identified more than 4,000 people with young-adult onset Hodgkin's lymphoma and 7,000 of their first-degree relatives.
The study showed that the risk of Hodgkin's lymphoma was nearly twice as high among close relatives of people with multiple sclerosis. Similarly, the risk of MS was more than doubled in relatives of people with Hodgkin's lymphoma.
The results appear in the May 19 issue of the Journal of the National Cancer Institute.
Researchers say the fact that these two diseases are clustered within families is consistent with the belief that the conditions may share similar risk factors and causes.
SOURCE: Hjalgrim, H. Journal of the National Cancer Institute, May 19, 2004; vol 96: pp 780-784.