Table 1

Effect of renal function and dose of cyanocobalamin on stroke reduction by B vitamins

TrialDose of   cyanocobalamin (μg)  Serum creatinine   (μmol/L*) B vitamins  ControlStroke
HR   (95% CI)  
P values
VISP† 32 40099.9 (55.7)97.2 (47.7)1.0 (0.8 to 1.3)0.80
VITATOPS‡ 33 50092.4 (40.3)91.4 (34.6)0.92 (0.81 to 1.06)0.25
DIVINe34 1000141.4 (97.2)123.8 (79.6)6.6 (0.8 to 54.4)0.08
SEARCH39 1000NANA  1.02 (0.86 to 1.21)NA
CSPPT35 065.95 (19.0)65.95 (19.0)0.79 (0.68 to 0.93)0.003
CSPPT35 0126.6 (72.7)130.6 (68.6)0.88 (0.33 to 2.36)0.81
eGFR<60§
CSPPT35 064.7 (13.8)64.6 (13.6)0.79 (0.67 to 0.92)0.003
Excluding eGFR<60§
NORVIT36 40091 (27)91 (24)0.83 (0.47 to 1.47)0.52
HOPE37 100088.4 (26.5)88.4 (26.5)0.75 (0.59 to 0.97)0.03
SU.Fol.OM338 2078.0 (70.0-88.0)78.0 (69.0–88.0)0.57 (0.33 to 0.97)0.04
  • Individual data were obtained from both VISP32 and VITATOPS33 trials. Reproduced with permission from Elsevier.12

  • *Data are presented as mean (SD), unless otherwise specified.

  • †Patients with an eGFR of less than 50 mL/min/1.73 m² had a mean eGFR rate (SD) of 38.7 mL/min/1.73 m² (9.2) (control 39.3 mL/min/1.73 m² (8.6); composite outcomes HR (95% CI) 1.01 (0.74 to 1.37; p=0.977)). Patients with an eGFR of 50 mL/min/1.73 m² or more had mean eGFR rate of 89.2 mL/min/1.73 m² (44.6) (control 87.3 (31.1); composite outcomes HR 0.92 (0.77 to 1.11; p=0.382)). Composite outcomes refer to myocardial infarction, stroke or death.

  • ‡Patients with an eGFR of 50 mL/min/1.73 m² or less had a mean eGFR rate (SD) of 38.6 mL/min/1.73 m² (10.0) (control 38.3 (9.5); composite outcomes HR (95% CI) 0.88 (0.59 to 1.32; p=0.54)). Patients with an eGFR of more than 50 mL/min/1.73 m² had a mean eGFR rate of 80.2 (18.1) (control 80.9 (18.3); composite outcomes HR 0.82 (0.68 to 0.98; p=0.03)). Composite outcomes refer to myocardial infarction, stroke or death.

  • §mL/min/1.73 m².

  • CSPPT, China Stroke Primary Prevention Trial; eGFR, estimated glomerular filtration rate (mL/min/1.73 m²); NA, not applicable; VISP, Vitamins Intervention for Stroke Prevention; VITATOPS, VITAmins TO Prevent Stroke.

  • SEARCH: Study of the Effectiveness of Additional Reductions of Cholesterol and Homocysteine