Table 3.
Relationship of amino acid levels with the odds of arsenic-induced skin lesions*
| Amino acids | N | Cases (%) | Crude | Adjusted† | ||
| Or (95% CI) | P value | Or (95% CI) | P value | |||
| Tryptophan | ||||||
| Per IQR | 112 | 56(50) | 0.48 (0.27 to 0.84) | 0.011 | 0.48 (0.27 to 0.86) | 0.013 |
| Quartiles | ||||||
| Q1 | 28 | 20 (71.40) | 1.00 (1.00 to 1.00) | Ref. | 1.00 (1.00 to 1.00) | Ref. |
| Q2 | 28 | 15 (53.60) | 0.50 (0.16 to 1.54) | 0.225 | 0.56 (0.16 to 1.98) | 0.370 |
| Q3 | 28 | 10 (35.70) | 0.12 (0.03 to 0.53) | 0.005 | 0.12 (0.02 to 0.60) | 0.010 |
| Q4 | 28 | 11 (39.30) | 0.19 (0.05 to 0.71) | 0.014 | 0.21 (0.05 to 0.84) | 0.028 |
| P for trend | 0.008 | 0.012 | ||||
| Phenylalanine | ||||||
| Per IQR | 112 | 56(50) | 0.57 (0.36 to 0.91) | 0.019 | 0.56 (0.33 to 0.94) | 0.028 |
| Quartiles | ||||||
| Q1 | 28 | 20 (71.40) | 1.00 (1.00 to 1.00) | Ref. | 1.00 (1.00 to 1.00) | Ref. |
| Q2 | 28 | 19 (67.90) | 0.79 (0.22 to 2.82) | 0.712 | 0.70 (0.18 to 2.76) | 0.609 |
| Q3 | 28 | 8 (28.60) | 0.18 (0.05 to 0.66) | 0.010 | 0.20 (0.05 to 0.77) | 0.019 |
| Q4 | 28 | 9 (32.10) | 0.25 (0.08 to 0.79) | 0.018 | 0.20 (0.05 to 0.75) | 0.017 |
| P for trend | <0.001 | 0.001 | ||||
| Leucine | ||||||
| Per IQR | 112 | 56(50) | 0.45 (0.25 to 0.82) | 0.019 | 0.43 (0.21 to 0.86) | 0.016 |
| Quartiles | ||||||
| Q1 | 28 | 21 (75.00) | 1.00 (1.00 to 1.00) | Ref. | 1.00 (1.00 to 1.00) | Ref. |
| Q2 | 28 | 14 (50.00) | 0.33 (0.11 to 1.03) | 0.057 | 0.31 (0.10 to 1.01) | 0.052 |
| Q3 | 28 | 11 (39.30) | 0.22 (0.07 to 0.68) | 0.009 | 0.22 (0.07 to 0.73) | 0.014 |
| Q4 | 28 | 10 (35.70) | 0.19 (0.06 to 0.59) | 0.004 | 0.19 (0.06 to 0.65) | 0.008 |
| P for trend | 0.003 | 0.007 | ||||
| Phenylalanylphenylalanine | ||||||
| Per IQR | 112 | 56(50) | 0.62 (0.36 to 1.04) | 0.070 | 0.71 (0.41 to 1.24) | 0.227 |
| Quartiles | ||||||
| Q1 | 27 | 21 (77.80) | 1.00 (1.00 to 1.00) | Ref. | 1.00 (1.00 to 1.00) | Ref. |
| Q2 | 29 | 14 (48.30) | 0.16 (0.03 to 0.75) | 0.021 | 0.14 (0.03 to 0.73) | 0.019 |
| Q3 | 28 | 9 (32.10) | 0.08 (0.02 to 0.39) | 0.002 | 0.09 (0.02 to 0.52) | 0.007 |
| Q4 | 28 | 12 (42.90) | 0.12 (0.02 to 0.57) | 0.008 | 0.11 (0.02 to 0.66) | 0.016 |
| P for trend | 0.006 | 0.023 | ||||
*Adjusted for plasma glucose, low-density lipoprotein, triglyceride and urinary dimethyl arsenate.
†Values are ORs (95% CIs) for arsenic-induced skin lesions from conditional logistic regression. Q1: the first quartile; Q2: the second quartile; Q3: the third quartile; Q4: the fourth quartile.