Therefore , although the overall effect of metformin on the concentration of serum Hcy was neutral , our results suggested that metformin could increase the concentration of Hcy when exogenous B-group vitamins or folic acid supplementation was not given
The aim of this systematic review is to assess whether metformin could change the concentration of serum homocysteine ( Hcy ) with and without simultaneous supplementation of B-group vitamins or folic acid .
Metformin increases total serum homocysteine levels in non-diabetic male patients with coronary heart disease.
It is known that the metabolism of homocysteine ( Hcy ) depends on the vitamins B6 , B12 and folate , and furthermore that metformin reduces serum vitamin B12 levels . In order to investigate whether metformin treatment affects serum total Hcy ( tHcy ) levels we performed an open , prospect i ve , r and omised study in 60 non-diabetic male patients with cardiovascular disease . After a 4-week run-in period with lovastatin 40 mg day-1 , and diet and lifestyle advice , patients were r and omised into two groups , both continuing the run-in treatment . One group received metformin up to 2000 mg day-1 , whereas the control group got no additional treatment . After 12 and 40 weeks of metformin treatment , tHcy levels increased moderately but significantly by 7.2 % ( p < 0.05 ) and 13.8 % ( p < 0.05 ) in the metformin group relative to the control group , whereas serum vitamin B12 levels decreased by 13.4 % ( p < 0.0005 ) and 17.7 % ( p < 0.0005 ) , respectively . Serum folate levels did not change after 12 weeks , but decreased by 8.0 % after 40 weeks ( p = 0.061 ) relative to the control group . Serum levels of total cysteine and methylmalonic acid ( MMA ) did not change . In conclusion , metformin treatment increased tHcy levels and decreased levels of vitamin B12 and folate . Since MMA levels were unchanged , it remains an open question whether the increase in tHcy levels is secondary to reduced vitamin B12 levels , folate levels or a combination of both
Therefore , although the overall effect of metformin on the concentration of serum Hcy was neutral , our results suggested that metformin could increase the concentration of Hcy when exogenous B-group vitamins or folic acid supplementation was not given
The aim of this systematic review is to assess whether metformin could change the concentration of serum homocysteine ( Hcy ) with and without simultaneous supplementation of B-group vitamins or folic acid .