Table 2.
Associations of the obstructive apnea–hypopnea index with subclinical interstitial lung disease on computed tomography in the Multi-Ethnic Study of Atherosclerosis
| Mean Percent HAA Increment Compared with oAHI < 5 Events/h (95% CI) |
Odds Ratio for ILA Compared with oAHI < 5 Events/h (95% CI) |
|||||||
|---|---|---|---|---|---|---|---|---|
| <5 Events/h | 5–15 Events/h | >15 Events/h | P Trend | <5 Events/h | 5–15 Events/h | >15 Events/h | P Trend | |
| Precision adjusted | 0 (Ref) | 1.4 (–1.2 to 3.9) | 7.2 (4.5 to 10) | <0.001 | 1 (Ref) | 1.32 (0.87 to 2.00) | 1.64 (1.36 to 1.98) | <0.001 |
| Adjusted | 0 | 0.2 (–0.2 to 2.7) | 4.0 (1.4 to 6.8) | 0.001 | 1 | 0.96 (0.62 to 1.51) | 1.35 (1.13 to 1.61) | <0.001 |
| Adjusted with BMI interaction terms | ||||||||
| <25 kg/m2 | 0 | 4.7 (0.1 to 9.5) | 6.1 (0.5 to 12.0) | 0.03 | 1 | 2.06 (1.16 to 3.6) | 2.31 (1.30 to 4.12) | 0.005 |
| 25–30 kg/m2 | 0 | −1.9 (–5.6 to 2.0) | 0.8 (–3.2 to 5.1) | 0.48 | 0.71 (0.35 to 1.43) | 0.51 (0.23 to 1.12) | 0.10 | |
| >30 kg/m2 | 0 | −3.1 (–7.5 to 1.5) | 2.7 (–1.6 to 7.3) | 0.03 | 0.77 (0.29 to 2.07) | 1.82 (1.13 to 2.93) | <0.001 | |
| Adjusted with smoking interaction term | ||||||||
| Never-smokers | 0 | 3.5 (–0.01 to 7.4) | 9.6 (5.6 to 13.6) | <0.001 | 1 | 0.73 (0.32 to 1.64) | 1.38 (0.84 to 2.28) | 0.01 |
| Ever-smokers | 0 | 0.3 (–3.0 to 3.8) | 5.2 (1.6 to 8.9) | 0.002 | 1 | 1.33 (0.75 to 2.35) | 1.50 (0.99 to 2.27) | 0.050 |
Definition of abbreviations: BMI = body mass index; CI = confidence interval; HAA = high-attenuation area; ILA = interstitial lung abnormality; oAHI = obstructive apnea–hypopnea index; Ref = reference category.
The precision-adjusted HAA model includes milliampere (mA) dose, imaged lung volume, and study site for HAA. Note that mA dose is BMI-based, and that this model adjusts for BMI greater than 30 and for BMI less than 20. The precision-adjusted ILA model includes only cluster-robust variance estimation to account for study site. The adjusted HAA model includes adjustment for age, sex, race, educational attainment, height, smoking status, cigarette pack-years, glomerular filtration rate, study site, percent emphysema, milliampere radiation dose, and total volume of imaged lung. The adjusted ILA model includes adjustment for age, sex, race, smoking status, cigarette pack-years, and cluster-robust variance estimation for study site.
For the HAA model: P = 0.08 for the interaction between oAHI and BMI, and P = 0.23 for the interaction between oAHI and smoking. For the ILA model, P = 0.04 for the interaction between nadir oAHI and BMI, and P = 0.46 for the interaction between oAHI and smoking.