Table 2.
Mean differences in concentrations of biomarkers of systemic injury and inflammation per 25% increase in the air pollutant concentrations measured over 48 hours among female cooks in rural Nicaragua, 2008.†
| Pollutant | N | Difference | 95% CI |
|---|---|---|---|
| CRP | |||
| Indoor PM2.5 | 48 | 7.4% | 0.7, 14.5 |
| Indoor CO | 51 | 4.8% | −0.5, 10.4 |
| Personal CO | 50 | 7.9% | 1.8, 14.3 |
| SAA | |||
| Indoor PM2.5 | 48 | 6.9% | −3.9, 18.9 |
| Indoor CO | 51 | 3.0% | −5.0, 11.6 |
| Personal CO | 50 | 1.9% | −7.1, 11.7 |
| sICAM | |||
| Indoor PM2.5 | 48 | 2.0% | −1.3, 5.4 |
| Indoor CO | 51 | 1.0% | −1.6, 3.6 |
| Personal CO | 50 | 2.4% | −0.5, 5.4 |
| sVCAM‡ | |||
| Indoor PM2.5 | 48 | 1.6 ng/ml | −1.1, 4.3 |
| Indoor CO | 51 | 1.8 ng/ml | −0.2, 3.8 |
| Personal CO | 50 | 2.7 ng/ml | 0.5, 5.1 |
| IL-1β | |||
| Indoor PM2.5 | 48 | 0.5% | −4.4, 5.7 |
| Indoor CO | 51 | 0.8% | −2.9, 4.8 |
| Personal CO | 50 | −1.6% | −5.6, 2.5 |
| IL-6 | |||
| Indoor PM2.5 | 48 | −6.7% | −41.8, 49.7 |
| Indoor CO | 51 | −10.5% | −37.2, 27.4 |
| Personal CO | 50 | 8.2% | −28.9, 64.6 |
| IL-8 | |||
| Indoor PM2.5 | 48 | −2.1% | −9.9, 6.4 |
| Indoor CO | 51 | −4.2% | −10.1, 2.0 |
| Personal CO | 50 | −3.1% | −9.6, 4.0 |
| TNF-α | |||
| Indoor PM2.5 | 48 | −6.5% | −15.1, 3.1 |
| Indoor CO | 51 | −4.0% | −11.0, 3.4 |
| Personal CO | 50 | −0.5% | −8.9, 8.7 |
All models were adjusted for age, body mass index, and education. Sample sizes less than 54 are due to missing pollutant or covariate data. With the exception of sVCAM, beta coefficients were entered into the formula ((1.25^β)-1) and multiplied by 100; therefore, we can interpret the estimate as a percent difference in inflammatory marker for each 25% increase in pollutant.
Values presented for sVCAM represent the mean change in units of ng/ml for each 1-unit increase in the natural-logarithmic transformed pollution variable.
Abbreviations: CI: confidence interval; CO: Carbon monoxide; CRP: C-reactive protein; IL-1β: interleukin 1-beta; IL-6: interleukin 6; IL-8; interleukin 8; PM2.5: Particulate matter with diameter <2.5 micrometers; SAA: serum amyloid A; sICAM: soluble intercellular adhesion molecule; sVCAM: soluble vascular cell adhesion molecule; TNF-α: tumor necrosis factor-alpha.