Proportion of study participants with vitamin B12 deficiency before and after RYGB surgery
| Before surgery | 6 months | 12 months | 24 months | 36 months | Δ6 month | Δ12 month | Δ24 month | Δ36 month | Definition of deficiency | |||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Year | Author | No | Per cent | No | Per cent | No | Per cent | No | Per cent | No | Per cent | (Per cent) | (Per cent) | (Per cent ) | (Per cent ) | |
| 2006 | Madan AK | 3/59 | 5.0 | 0/56 | 0* | 0/36 | 0* | – | – | – | – | −5.0 | −5.0 | – | – | NR |
| 2009 | Toh SY | 1/88 | 1.0 | – | – | 6/56 | 11.0 | – | – | – | – | – | 10.0 | – | – | <196 pg/mL |
| 2012 | Blume CA | 5/170 | 2.9 | 6/170 | 3.5 | 6/170 | 3.5 | 9/170 | 5.3 | 12/170 | 7.1 | 0.6 | 0.6 | 2.4 | 4.2 | <211 pg/mL |
| 2013 | Moizé V | 5/294 | 1.8 | 9/294 | 2.9 | 18/294 | 6.2 | 14/259 | 5.5 | 12/203 | 5.8 | 1.1 | 4.4 | 3.7 | 4.0 | <250 pg/mL |
| 2014 | Ledoux S | 7/144 | 5.0 | – | – | 23/144 | 16.0 | – | – | 13/115 | 11.0 | – | 11.0 | – | 6.0 | <190 pg/mL |
| Summary estimate (95% CI) | 2.3 (1.1 to 3.6) | 1.9 (0 to 4.4)† | 6.5 (1.8 to 11.1) | 5.4 (3.3 to 7.6) | 7.2 (4.6 to 9.7) | −0.3 (−3.3 to 2.7) | 3.6 (−1.2 to 8.4) | 3.2 (0.7 to 5.8) | 4.4 (1.8 to 7.0) | |||||||
| I2 | 22.9 | 85.8 | 92.8 | 0.0 | 17.1 | 48.8 | 77.7 | 0.0 | 0.0 | |||||||
*Data were included in the analysis with a continuity correction factor of 0.01.
†The lower limits of 95% CI were truncated as zero due to negative values.
NR, not reported; RYGB, Roux-en-Y gastric bypass.