Multivariable logistic regression for restrictive spirometry pattern (vs normal spirometry) in 100 patients with sickle cell anaemia aged 6–18 years from the DR Congo
| Predictor | Restrictive spirometry pattern* | ||
| OR | 95% CI | P value | |
| Female sex | 3.8 | 1.2 to 11.6 | 0.02 |
| Annual increase of age, years | 1.3 | 1.1 to 1.5 | 0.005 |
| Frequent pain crises† | 0.4 | 0.1 to 1.4 | 0.16 |
| zBMI <−2 | 5.4 | 1.6 to 17.6 | 0.006 |
ZBMI and zHeight values based on WHO growth charts.7
Spirometry z-scores based on Global Lung Function Initiative 2012 equations for African Americans.8
*Restrictive pattern=FVC <LLN and FEV1/FVC ≥LLN; only covariates with p value <0.20 were included in the final model.
†At least three episodes in the last 12 months. Pain crisis defined as bone pain in the chest, extremities or other areas that required at least 24 hours of analgesic therapy.
zBMI, z-score body mass index; zHeight, z-score height.