Table 2.
Putative Markers Characterizing the Recurrent Wheezing Group With Respect to the No Wheezing Group, Based on Merging the Results of Multivariate and Univariate Data Analysis
| Data Seta | RetentionTime (min) | Mass to Charge Ratio | Typeb | Area Under the ROC Curve, Median (95% CI) | P c | Putatively Annotated Compound |
|---|---|---|---|---|---|---|
| POS | 0.5317 | 205.1539 | No wheeze > wheeze | 0.76 (.61–.90) | >.01 | 3-hydroxy-N6,N6,N6-trimethyl-L-lysine |
| POS | 0.6604 | 204.0857 | No wheeze > wheeze | 0.69 (.51–.86) | .01 | N2-acetyl-L-aminoadipate |
| POS | 0.5315 | 189.1593 | No wheeze > wheeze | 0.73 (0.57–0.89) | .01 | 7,8-diaminononanoate |
| NEG | 0.7488 | 191.0192 | No wheeze > wheeze | 0.72 (0.56–0.87) | .01 | Isocitrate |
| NEG | 0.7517 | 111.0083 | No wheeze > wheeze | 0.72 (0.56–0.87) | .01 | 3-furoic acid |
| POS | 0.654 | 310.1133 | No wheeze > wheeze | 0.71 (0.55–0.87) | .04 | N-acetylneuraminic acid |
| NEG | 1.04 | 160.061 | No wheeze > wheeze | 0.69 (0.52–0.86) | .02 | L-2-aminoadipic acid |
| POS | 0.758 | 163.0417 | No wheeze > wheeze | 0.76 (0.60–0.92) | .02 | 1,2-dihydroxy-3-keto-5-methylthiopentene |
| NEG | 1.3627 | 103.0397 | No wheeze > wheeze | 0.71 (0.54–0.87) | .02 | (S)-3-hydroxybutyric acid |
| POS | 0.5053 | 128.0695 | No wheeze > wheeze | 0.67 (0.50–0.84) | .02 | D-1-piperidine-2-carboxylic acid |
| POS | 0.7558 | 181.0526 | No wheeze > wheeze | 0.71 (0.54–0.87) | .02 | 5-methylthioribose |
| POS | 0.5872 | 114.0655 | No wheeze > wheeze | 0.70 (0.53–0.86) | .03 | Creatinine |
| POS | 0.5137 | 198.0861 | No wheeze > wheeze | 0.69 (0.51–0.86) | .03 | N-acetyl-L-histidine |
| NEG | 0.7499 | 173.0087 | No wheeze > wheeze | 0.67 (0.50–0.84) | .03 | Aconitic acid |
| NEG | 0.9233 | 129.0189 | No wheeze > wheeze | 0.69 (0.52–0.85) | .04 | Itaconic acid |
| NEG | 0.9225 | 111.0083 | No wheeze > wheeze | 0.69 (0.52–0.85) | .04 | 2-furoic acid |
| NEG | 4.0527 | 137.0602 | No wheeze > wheeze | 0.70 (0.52–0.87) | .04 | 2-(4-hydroxyphenyl)ethanol |
| POS | 1.496 | 146.0804 | No wheeze > wheeze | 0.68 (0.51–0.84) | .04 | N-butyryl glycine |
| NEG | 0.9221 | 191.0192 | No wheeze > wheeze | 0.68 (0.51–0.84) | .05 | Citric acid |
| NEG | 0.6123 | 165.04 | No wheeze > wheeze | 0.71 (0.53–0.88) | .05 | Ribonic acid |
| NEG | 0.9215 | 87.0082 | No wheeze > wheeze | 0.69 (0.52–0.85) | .05 | Pyruvate |
| NEG | 0.9238 | 173.0087 | No wheeze > wheeze | 0.68 (0.51–0.85) | .07 | Dehydroascorbic acid |
| POS | 0.7051 | 204.1226 | No wheeze > wheeze | 0.38 (0.19–0.57) | .08 | Acetylcarnitine |
| NEG | 0.8199 | 145.0137 | Wheeze > no wheeze | 0.75 (0.59–0.90) | .01 | Oxoglutaric acid |
| NEG | 3.1389 | 143.0352 | Wheeze > no wheeze | 0.76 (0.60–0.91) | .01 | (E)-2-methylglutaconic acid |
| POS | 0.5865 | 156.0417 | Wheeze > no wheeze | 0.66 (0.49–0.83) | .01 | N-methylethanolamine phosphate |
| POS | 4.275 | 281.1128 | Wheeze > no wheeze | 0.70 (0.53–0.86) | .02 | L-beta-aspartyl-L-phenylalanine |
| POS | 4.0403 | 246.1696 | Wheeze > no wheeze | 0.65 (0.48–0.82) | .04 | Pivaloylcarnitine |
| POS | 0.8652 | 258.1071 | Wheeze > no wheeze | 0.64 (0.46–0.81) | .04 | 5-methylcytidine |
Abbreviations: CI, confidence interval; ROC, receiver operating characteristic curve.
aVariables were acquired in positive (POS) or negative (NEG) ionization modes.
bVariables with higher levels in the no wheezing group are described as “no wheeze > wheeze,” and variables with higher levels in the recurrent wheezing group are described as “wheeze > no wheeze.”
cBy the t test (variables with a P value of <.05 had a q value of <.15).