Table 3.
Association between age and inflammatory marker levels in ARDS patients (mediation step 3)
| Coefficient [95% CI] | p value | Coefficient [95% CI]* | p value | Adjusted R2 | |
|---|---|---|---|---|---|
| IL-6 | |||||
| Young adults | Reference | NA | Reference | NA | 0.152 |
| Middle-aged adults | − 0.33 [− 0.73, 0.08] | 0.113 | − 0.30 [− 0.69, 0.06] | 0.117 | |
| Elderly | − 0.40 [− 0.81, 0.01] | 0.057 | − 0.33 [− 0.73, 0.06] | 0.100 | |
| IL-8 | |||||
| Young adults | Reference | NA | Reference | NA | 0.247 |
| Middle-aged adults | − 019 [− 0.54, 0.16] | 0.478 | − 0.06 [− 0.37, 0.26] | 0.767 | |
| Elderly | − 0.48 [− 0.84, − 0.12] | 0.019 | − 0.25 [− 0.58, 0.07] | 0.148 | |
| IL-10 | |||||
| Young adults | Reference | NA | Reference | NA | 0.203 |
| Middle-aged adults | − 0.30 [− 0.62, 1.02] | 0.174 | − 0.21 [− 0.51, 0.08] | 0.133 | |
| Elderly | − 0.42 [− 0.75, − 0.09] | 0.032 | − 0.26 [− 0.57, 0.04] | 0.058 | |
| IL-1β | |||||
| Young adults | Reference | NA | Reference | NA | 0.053 |
| Middle-aged adults | − 0.06 [− 0.20, 0.09] | 0.461 | − 0.01 [− 0.16, 0.14] | 0.854 | |
| Elderly | − 0.00 [− 0.15, 0.15] | 0.957 | 0.07 [− 0.09, 0.22] | 0.392 | |
| TNF-α | |||||
| Young adults | Reference | NA | Reference | NA | 0.009 |
| Middle-aged adults | − 0.04 [− 0.17, 0.08] | 0.522 | − 0.02 [− 0.15, 0.11] | 0.671 | |
| Elderly | 0.05 [− 0.08, 0.18] | 0.434 | 0.08 [− 0.06, 0.22] | 0.248 | |
| INF-γ | |||||
| Young adults | Reference | NA | Reference | NA | 0.031 |
| Middle-aged adults | − 0.16 [− 0.45, 0.12] | 0.262 | − 0.11 [− 0.39, 0.18] | 0.524 | |
| Elderly | − 0.35 [− 0.65, − 0.06] | 0.017 | − 0.24 [− 0.55, 0.06] | 0.127 | |
| MMP-8 | |||||
| Young adults | Reference | NA | Reference | NA | 0.044 |
| Middle-aged adults | − 0.23 [− 0.63, 0.18] | 0.271 | − 0.19 [− 0.60, 0.21] | 0.356 | |
| Elderly | − 0.03 [− 0.45, 0.38] | 0.869 | − 0.01 [− 0.40, 0.41] | 0.959 | |
| TIMP-1 | |||||
| Young adults | Reference | NA | Reference | NA | 0.111 |
| Middle-aged adults | − 0.08 [− 0.34, 0.18] | 0.537 | − 0.03 [− 0.29, 0.21] | 0.776 | |
| Elderly | − 0.13 [− 0.40, 0.13] | 0.328 | 0.00 [− 0.26, 0.26] | 0.996 | |
Data is presented as beta-coefficient (β) with a 95% confidence interval [CI]. All biomarkers are log-transformed. *Adjusted for ethnic background, gender, admission type, readmission, direct hit for ARDS, Charlson Comorbidity Index, APACHE-IV score adjusted for age, immunodeficiency, tidal volume per predicted body weight, and positive end-expiratory pressure. A p value < 0.05 was considered as statistically significant. IL interleukin, TNF-α tumor necrosis factor alpha, INF-γ, interferon gamma, MMP-8 matrix metalloproteinase-8, and TIMP-1 metallopeptidase inhibitor-1. Goodness of fit, adjusted R2. NA not applicable