Effects of once-a-week or daily folic acid supplementation on red blood cell folate concentrations in women.

OBJECTIVE: Our aim was to determine if a once-a-week folic acid supplement increases women's red blood cell folate to concentrations (>905 nmol/l) that are associated with a low risk of bearing a child with a neural tube defect. DESIGN: Randomized control trial. SETTING: General community. SUBJECTS: In total, 114 nonpregnant women (18-40 y) volunteers, with red blood cell folate concentrations between 295 and 905 nmol/l at screening. INTERVENTION: Women were randomized to receive a once-a-week 2800 microg folic acid supplement, a daily 400 microg folic acid supplement or a daily placebo for 12 weeks. RESULTS: The mean (95% CI) red blood cell folate concentrations increased during the 12-week intervention from 608 (553-668) to 900 (828-978) in the weekly folic acid group (P<0.05) and from 615 (560-677) to 1053 (957-1158) nmol/l in the daily group (P<0.05) during the trial. At week 12, 49% of women ingesting the weekly folic acid supplement had red blood cell folate concentrations greater than 905 nmol/l compared to 74% of women ingesting the daily supplement. CONCLUSION: A once-a-week 2800 microg folic acid supplement can increase women's red blood cell folate to concentrations associated with a reduced risk of bearing a child with a neural tube defect, but is less effective than a 400 microg daily supplement. Use of a weekly folic acid supplement over at least 12 weeks before conception by women of child-bearing age may prevent neural tube defects. FUNDING: The Otago Medical Research Foundation (Laurenson Award). Healtheries (New Zealand) provided the supplements.

Calcium dobesilate in diabetic retinopathy. A retrospective controlled study.

The effect of calcium dobesilate (Doxium) therapy on the evolution of diabetic retinopathy has been assessed in a retrospective study. 54 patients with diabetic retinopathy received calcium dobesilate (average 650 mg/day) for 6-30 months (average 18 months) and were compared to a correspondingly selected control group. The patients were divided into three subgroups (mild, moderate, and severe diabetic retinopathy). Microaneurysms, blot hemorrhages, striate hemorrhages, and hard exudates were assessed semiquantitatively from panorama fundus photographs, using a scoring system. The effect of calcium dobesilate was statistically significant for cases with moderate background diabetic retinopathy on summing up the scores of the various retinal lesions. There was no favorable effect on diabetic maculopathy or visual acuity. In the proliferative stages of diabetic retinopathy, photocoagulation is offering, in the majority of cases, the only chance to slow down the progression of this disease; however, drug therapy might be beneficial in nonproliferative diabetic retinopathy.