ABSTRACT
Objectives: To investigate the association between oedema in the subcutaneous fat of the lumbar region during routine magnetic resonance imaging (MRI) and patients’ age, gender and body mass index (BMI).
Methods: One hundred and forty-nine consecutive examinations of 95 females and 54 males, 18 years and older, scanned at 1.5T between October 1, 2010, and December 31, 2010, were reviewed. Presence and extent of oedema were determined. Oedema was sized on the anatomical segments. Data were analysed using tests for means, odd’s ratio (OR), Chi-squared test, McNemar’s test, linear and backward stepwise multiple regression and analysis of variance (ANOVA).
Results: Patients with oedema had significantly higher BMI (30.3 kg/m2 vs 24.9 kg/m2, p < 0.001), and were older (49.9 years vs 43.9 years, p = 0.01) than those without oedema. The OR for oedema in obese vs non-obese patients was 8.6. The Chi-squared and McNemar tests were significant, p = 0 and p < 0.001, respectively. Body mass index and age predicted oedema on backward stepwise regression and, on ANOVA, at 23.6% and 4.7%, respectively. Males were marginally less likely to have oedema (p = 0.056) and had marginally less oedema (p = 0.056) than females.
Conclusion: Body mass index and age, but not gender, predict oedema. Body mass index predicts oedema five times as much as age.