[Homocysteine, folate therapy and outcome in hemodialysis: results from a prospective study]

Despite the well-known effectiveness of folate therapy on hyperhomocysteinemia in hemodialysis, its benefits on outcome are still unclear.

Sixty-five patients on thrice-weekly maintenance hemodialysis lasting more than 3 months were followed up for 1 year after stratification by predialysis homocysteine level (tHcy). Parenteral folate (25 mg quarterly) and cobalamine (1 mg quarterly) therapy was started only if the tHcy levels were > 30 uM/L at baseline or at scheduled retests (every 7 months). End points were overall mortality and new ischemic events (affecting heart, brain, or lower extremities).

58.5% of patients received treatment at baseline and achieved a 60% reduction of tHcy. 38.1% progressed to levels of over 30 tHcy at 6 months and were placed on treatment. No other major changes occurred until the end of the study. An excess of both overall mortality (30.8% versus 12.1%; p = 0.075) and vascular morbidity (38.5% versus 12.1%; p = 0.03) occurred in initially untreated patients,those presenting without baseline intermediate to severe hyperhomocysteinemia.

In undertaking hemodialysis, it appears that treating intermediate to severe hyperhomocysteinemia carries better prognosis for outcome than untreated moderate or absent hyperhomocysteinemia. It is uncertain if the benefit of therapy is valid, or if it is confounded by an association between lower tHhy and hidden malnutrition or concomitant diseases.