Contributing factors to the plasma albumin level at diagnosis of hematological malignancy

Many factors contribute to the plasma albumin (PA) level. We aimed to quantify different factors’ relative contribution to the PA level when diagnosing hematological malignancy (HM). The study was a population-based registry study including patients with HM in a Danish region. We applied multivariate linear regression analyses with C-reactive protein (CRP), WHO performance score (WHO-PS), age, sex, comorbidity, and HM type as exposures and the PA level on the day of the HM diagnosis (DX) as the outcome. The relative contribution of each exposure was determined as a percentage of the models’ coefficient of determination (R²). In total, 2528 patients with HM had PA measured on DX. In the model comprising all exposures, CRP contributed with 65.8% to the R² of 0.389 whereas 3 variables (CRP, WHO-PS, HM type) together contributed with 96.1%. When CRP was excluded from the model, R² declined to 0.215 and the WHO-PS contributed with 96%. Other models, including separate analyses for each HM type, corroborated these results, except in myeloma patients where WHO-PS contributed with 61.1% to the R² of 0.234. The inflammation biomarker CRP was the main predictor of the PA level on DX. The WHO-PS also contributed to the PA level on DX whereas the remaining factors (HM type, age, sex, and comorbidity) were of much less importance.