Table 4.
Geometric means and 95% confidence intervals (CIs)a of plasma SAM concentrations (nmol/L) by quartiles of one-carbon metabolism nutrients and metabolitesb
| Quartiles of plasma concentrations | ptrend | ||||
|---|---|---|---|---|---|
| 1 (lowest) | 2 | 3 | 4 (highest) | ||
| Betaine | |||||
| Men | 63.0 (58.8 – 67.6) | 65.9 (61.5 – 70.8) | 67.7 (63.0 – 72.6) | 70.9 (66.2 – 76.0) | 0.02 |
| Women | 56.2 (48.9 – 64.6) | 59.7 (51.7 – 69.0) | 57.5 (50.0 – 66.1) | 61.5 (53.2 – 71.0) | 0.08 |
| All subjects | 60.7 (57.5 – 64.0) | 60.2 (57.2 – 63.5) | 61.6 (58.3 – 65.0) | 65.1 (61.7 – 68.7) | 0.03 |
| Choline | |||||
| Men | 59.5 (55.7 – 63.5) | 63.4 (59.1 – 68.0) | 74.0 (69.4 – 78.9) | 70.7 (66.1 – 75.6) | <0.0001 |
| Women | 55.8 (48.5 – 64.2) | 56.8 (49.3 – 65.4) | 60.1 (52.3 – 69.1) | 61.3 (53.0 – 71.0) | 0.02 |
| All subjects | 57.5 (54.5 – 60.6) | 59.3 (56.4 – 62.4) | 65.8 (62.3 – 69.4) | 65.4 (62.1 – 68.9) | <0.0001 |
| Folate | |||||
| Men | 64.8 (60.5 – 69.5) | 63.8 (59.5 – 68.4) | 67.1 (62.5 – 72.0) | 72.1 (67.1 – 77.4) | 0.02 |
| Women | 56.8 (49.2 – 65.6) | 57.0 (49.5 – 65.7) | 57.7 (49.8 – 66.9) | 59.7 (51.9 – 68.8) | 0.24 |
| All subjects | 60.2 (57.2 – 63.4) | 61.1 (57.8 – 64.5) | 61.8 (58.6 – 65.1) | 64.8 (61.3 – 68.5) | 0.03 |
| Hcy | |||||
| Men | 67.5 (62.8 – 72.4) | 67.9 (63.4 – 72.6) | 65.5 (61.2 – 70.0) | 67.4 (62.7 – 72.5) | 0.87 |
| Women | 57.8 (49.8 – 67.0) | 55.8 (48.3 – 64.5) | 59.3 (51.7 – 67.9) | 57.2 (49.3 – 66.4) | 0.92 |
| All subjects | 62.3 (58.9 – 65.9) | 60.4 (57.3 – 63.7) | 65.0 (61.6 – 68.6) | 56.9 (56.9 – 63.4) | 0.56 |
| Methionine | |||||
| Men | 56.9 (53.4 – 60.6) | 64.1 (60.1 – 68.3) | 71.5 (67.3 – 76.0) | 77.1 (72.3 – 82.2) | <0.0001 |
| Women | 54.6 (48.0 – 62.2) | 57.2 (49.7 – 65.8) | 64.0 (55.7 – 73.5) | 67.0 (58.2 – 77.2) | <0.0001 |
| All subjects | 55.5 (52.9 – 58.2) | 59.0 (56.1 – 62.1) | 65.9 (62.7 – 69.3) | 70.8 (67.3 – 74.6) | <0.0001 |
| SAH | |||||
| Men | 60.7 (56.4 – 65.2) | 63.9 (59.7 – 68.5) | 72.9 (68.1 – 78.1) | 70.3 (65.3 – 75.6) | 0.006 |
| Women | 52.7 (45.9 – 60.5) | 59.1 (51.3 – 67.9) | 61.9 (53.8 – 71.0) | 60.7 (52.6 – 69.9) | 0.005 |
| All subjects | 55.7 (52.8 – 58.7) | 61.3 (58.3 – 64.5) | 65.6 (62.2 – 69.1) | 65.2 (61.7 – 68.8) | <0.0001 |
| Vitamin B6 | |||||
| Men | 67.1 (62.5 – 72.1) | 65.7 (61.3 – 70.3) | 63.5 (59.3 – 68.1) | 71.5 (66.5 – 76.9 | 0.17 |
| Women | 57.3 (49.7 – 66.2) | 55.2 (47.8 – 63.7) | 59.1 (51.4 – 68.0) | 59.6 (51.7 – 68.6) | 0.19 |
| All subjects | 61.8 (58.8 – 65.1) | 59.5 (56.4 – 62.8) | 61.7 (58.4 – 65.1) | 64.9 (61.4 – 68.6) | 0.046 |
| Vitamin B12 | |||||
| Men | 68.3 (63.6 – 73.3) | 64.0 (59.8 – 68.5) | 65.4 (61.0 – 70.0) | 70.3 (65.4 – 75.6) | 0.41 |
| Women | 57.0 (49.2 – 66.0) | 58.2 (50.4 – 67.2) | 57.3 (49.8 – 66.0) | 58.8 (51.1 – 67.7) | 0.56 |
| All subjects | 60.9 (57.7 – 64.2) | 61.0 (57.9 – 64.3) | 62.1 (58.9 – 65.5) | 63.5 (60.1 – 67.1) | 0.19 |
a
Adjusted for age at blood draw, BMI, smoking status, serum creatinine concentrations and gender (for all subjects);
b
One-carbon metabolism metabolites: SAM, S-adenosylmethionine; SAH, S-adenosylhomocysteine; Hcy, total homocysteine.