Raised serum IgG levels in hypertension.

Serum IgG levels were significantly higher in 118 severely hypertensive patients compared with a group of 163 normotensive blood donors, matched for age and sex. Serum IgA and IgM were the same in both groups. Raised levels of serum IgG were found in patients who had never been treated for hypertension, as well as in those who were treated with methyldopa or other hypotensive drugs.It is suggested that the raised levels of serum IgG may be an index of vascular damage induced by hypertension.