Total Plasma Protein in Very Preterm Babies: Prognostic Value and Comparison with Illness Severity Scores

Abstract

ObjectiveWe aimed to investigate the predictive value for severe adverse outcome of plasma protein measurements on day one of life in very preterm infants and to compare total plasma protein levels with the validated illness severity scores CRIB, CRIB-II, SNAP-II and SNAPPE-II, regarding their predictive ability for severe adverse outcome.MethodsWe analyzed a cohort of infants born at 24–31 weeks gestation, admitted to the tertiary intensive care unit of a university hospital over 10.5 years. The outcome measure was “severe adverse outcome” defined as death before discharge or severe neurological injury on cranial ultrasound. The adjusted odd ratio (aOR) and 95% confidence interval (95% CI) of severe adverse outcome for hypoproteinemia (total plasma protein level <40 g/L) was calculated by univariate and multivariate analyses. Calibration (Hosmer-Lemeshow goodness-of-fit) was performed and the predictive ability for severe adverse outcome was assessed for total plasma protein and compared with CRIB, CRIB-II, SNAP-II and SNAPPE-II, by calculating receiver operating characteristic (ROC) curves and their associated area under the curve (AUC).Results761 infants were studied: 14.4% died and 4.1% survived with severe cerebral ultrasound findings. The aOR of severe adverse outcome for hypoproteinemia was 6.1 (95% CI 3.8–9.9). The rank order for variables, as assessed by AUCs and 95% CIs, in predicting outcome was: total plasma protein [0.849 (0.821–0.873)], SNAPPE-II [0.822 (0.792–0.848)], CRIB [0.821 (0.792–0.848)], SNAP-II [0.810 (0.780–0.837)] and CRIB-II [0.803 (0.772–0.830)]. Total plasma protein predicted severe adverse outcome significantly better than CRIB-II and SNAP-II (both p<0.05). Calibration for total plasma protein was very good.ConclusionsEarly hypoproteinemia has prognostic value for severe adverse outcome in very preterm, sick infants. Total plasma protein has a predictive performance comparable with CRIB and SNAPPE-II and greater than other validated severity scores.

Low Plasma Protein Levels at Birth Are Associated with Poor Cardiovascular Adaptation and Serious Adverse Outcome in Infants with Gestational Age <32 Weeks: The ProHémie Study

“…In summary, this study endorses the results of previous studies on the prognostic value of total plasma protein levels in very preterm infants [4,5], and confirms the research hypothesis that plasma protein levels are associated with cardiovascular function during transition. In this cohort, hypoproteinemia was significantly associated with hypotension during the first day of life and with lower SVR, even after the adjustment for gestational age.…”

“…In the present cohort study, we could confirm our previous retrospective findings [4,5] that early hypoproteinemia is strongly associated with severe adverse outcome, defined as death or survival with severe neurological injury on cranial ultrasound in very preterm infants.…”

“…In 2 previous reports [4,5,] we demonstrated that early hypoproteinemia (total plasma protein levels <40 g/L on the first day of life) is a strong independent factor in predicting severe adverse outcome (death or survival with major neurological abnormalities) in infants born at 24-31 weeks of gestation.…”

“…Protein concentration was determined using the COBAS® 6000 automatic analyzer (Roche, Germany) and hypoproteinemia was defined as a total protein level <40 g/L on the blood sample at 12 h of life [4,5,9]. …”

“…The outcome measure was severe adverse outcome, defined as death or severe (grade 3 or 4) intraventricular hemorrhage according to the Papile grading system or cystic periventricular leukomalacia occurring before infants' discharge from hospital [4,5]. Cranial ultrasounds were routinely performed during the infant hospital stay according to the following protocol: days 1, 3, 7, 10, 15 and then at least every 2 weeks or more often as clinically indicated, until discharge.…”