Table 3.
The significant adjusted associations between long-term exposure windows to temperature with metabolomics (multi-pollutant models) at ENT95% significance level
| Biochemical | Super-Pathway | Sub-Pathway | Beta (SE) for individual metabolites | P-value for individual metabolites | ICA_factor2 Weight | ICA_factor2 Rank |
|---|---|---|---|---|---|---|
| Heptanoate (7:0) | Lipid | Medium Chain Fatty Acid | −0.209 (0.039) | 1.87E-07 | −0.282 | 104 |
| Inosine | Nucleotide | Purine Metabolism, (Hypo)Xanthine/Inosine containing | −0.368 (0.083) | 1.71E-05 | 0.892 | 1 |
| Guanosine | Nucleotide | Purine Metabolism, Guanine containing | −0.348 (0.071) | 2.23E-06 | 0.329 | 78 |
| X - 24,970 | Un-identified | – | 0.34 (0.057) | 1.50E-08 | 0.360 | 63 |
| X - 24,431 | Un-identified | – | 0.215 (0.05) | 2.91E-05 | 0.160 | 190 |
| X - 23,636 | Un-identified | – | 0.161 (0.026) | 5.00E-09 | 0.141 | 214 |
These models were linear mixed-effect regression models (LMEM) with random participant-specific intercepts and simultaneously adjusted for PM2.5, NO2, O3, and temperature (multi-pollutant models) for the same exposure window
Beta (SE) and p-values presented are from individual metabolites analysis
All models were adjusted for age (years), body mass index (kg/m2), cigarette pack-years, alcohol intake (< or ≥ 2 drinks per day), socioeconomic status (income payment and years of education), season (warm/cold), and relative humidity
Significant metabolites at ENT95% significance level only are presented
ICA_factor2 rank represents the rank of the corresponding metabolite contributing to factor 2 from the independent component analysis (ICA). Higher rank (and higher weights) means higher contribution to factor 2 of the ICA. We show alongside the weights and ranks of each metabolite that contributes to factor 2 from the ICA only because it was the only significant factor
Range of facto2- ICA rank is from 1 to 1158 i.e., number of examined metabolites. Range of facto2- ICA weight is from −1 to 1
The metabolites with an X-XXXX format are unknown (to date Metabolon has not been able to name the metabolite) but reproducible (Metabolon is reliably able to characterize this metabolite in multiple samples and studies)
Abbreviations: ENT Effective/independent number of tests, PM2.5 Particulate matter ≤2.5 μm, NO2 Nitrogen dioxide, and O3 Ozone, ICA Independent component analysis, SE Standard error, NS Not significant at the ENT95% level