People vaccinated against hepatitis B triple their risk of developing multiple sclerosis over the following three years, a study in the current issue of the journal Neurology says (Neurology 2004;63:838-42).

Researchers led by Dr Miguel Hernán of Harvard School of Public Health analysed the United Kingdom's general practice research database, which follows a representative sample of over three million British patients.

They found 163 cases of multiple sclerosis that had first been diagnosed in the period 1993-2001 and which met the study's criteria on record keeping. Also analysed were 1604 matched controls who did not have multiple sclerosis.

The report's key finding …