Table 3.
Risk estimates of primary cardiovascular outcome for folic acid intervention versus control in pooled and stratified analysis by pertinent factors
| Stratification Variables | Primary CVD Events/Total Subjects |
RR | 95% CI | P | |
|---|---|---|---|---|---|
| Active | Control | ||||
| Overall (12–18) | 391/2038 | 431/1848 | 0.85 | 0.76, 0.96 | 0.009 |
| Intervention duration | |||||
| ≤24 months (12,15,17,18) | 164/813 | 155/614 | 0.88 | 0.72, 1.06 | 0.17 |
| >24 months (13,14,16) | 227/1225 | 276/1234 | 0.84 | 0.72, 0.98 | 0.02 |
| Hcy lowering | |||||
| ≤20% (14,18) | 86/498 | 69/327 | 0.99 | 0.66, 1.48 | 0.95 |
| >20% (12,13,15–17) | 305/1540 | 362/1521 | 0.83 | 0.73, 0.95 | 0.007 |
| Folic acid fortification | |||||
| yes (16–18) | 291/1701 | 305/1515 | 0.88 | 0.76, 1.02 | 0.10 |
| yes and Hcy lowering >20% (16,17) | 249/1359 | 289/1347 | 0.85 | 0.73, 0.99 | 0.04 |
| no or partly (12–15) | 100/337 | 126/333 | 0.80 | 0.65, 0.99 | 0.04 |
| Treatment regimen | |||||
| folic acid only (12,14,15) | 83/300 | 94/282 | 0.83 | 0.65, 1.06 | 0.14 |
| folic acid and vitamins B6 and B12 (13,16–18) | 308/1738 | 337/1566 | 0.86 | 0.75, 0.99 | 0.03 |
| Daily folic acid dose | |||||
| <5 mg (13,15,17) | 126/457 | 160/467 | 0.82 | 0.68, 0.99 | 0.04 |
| ≥5 mg (12,14,16,18) | 265/1581 | 271/1381 | 0.88 | 0.75, 1.02 | 0.09 |
| Pre-existing conditions | |||||
| ESRD (12,13,15,17,18) | 181/850 | 187/665 | 0.85 | 0.71, 1.01 | 0.06 |
| ESRD/ACKD (14,16) | 210/1188 | 244/1183 | 0.86 | 0.73, 1.01 | 0.07 |