Impact of red blood cells count on the relationship between high density lipoproteins and the prevalence and extent of coronary artery disease: a single centre study [corrected].

We have hypothesized that high red blood cells (RBC) count can potentially play an atheroprotective role in patients with coronary atherosclerosis. We, therefore, have investigated the relationship between high density lipoproteins cholesterol (HDL-C) and RBC levels in patients undergoing coronary angiography. Coronary artery disease (CAD) is a major cause of mortality. Impaired lipid profile represents a major risk factor for atherosclerosis. High density lipoprotein (HDL) is a key factor in atherosclerosis disease development. RBC can mimic HDL's reverse cholesterol transportation with a potential atheroprotective role. Coronary angiography has been evaluated in 3,534 patients. Fasting samples were collected for haematology and lipids levels assessment. Coronary disease was defined for at least 1 vessel stenosis >50 %. Patients were divided according to HDL-C and RBC tertiles. Lower HDL-C was significantly associated to the prevalence of CAD (84.8 vs 78.5 vs 67.3 %, p ≤ 0.001; adjusted OR [95 % CI] = 1.55 [1.3-1.8], p < 0.001) and severe CAD (30 % vs 30 % vs 24.4 %, p = 0.002; adjusted OR [95 % CI] = 1.08 [1.01-1.16], p = 0.02), this relationship was maintained even dividing our population according to RBC tertiles (p < 0.001).In conclusion, HDL-C levels are directly related to RBC count and inversely to the prevalence and extent of coronary disease. Higher RBC levels can reduce the risk of CAD in patients with lower HDL-C levels, suggesting an important atheroprotective role.

Early in-hospital variation of red blood cell distribution width predicts mortality in patients with acute heart failure.

BACKGROUND: Some studies showed that the value of red blood cell distribution width (RDW) at admission may predict clinical outcomes in patients with acutely decompensated heart failure (ADHF). Therefore, this study was planned to investigate whether in-hospital variations of RDW may also predict mortality in this condition. METHODS: The final study population consisted of 588 patients admitted to the local Emergency Department (ED), who were hospitalized for ADHF. The RDW was measured at ED admission and after 48h and 96h of hospital stay. In-hospital variations from admission value, expressed as absolute variation (DeltaRDW) or percent variation (Delta%RDW), were then correlated with 30- and 60-day mortality. RESULTS: Overall, 87 (14.8%) and 118 (20.1%) patients with ADHF died at 30 or 60days of follow-up. Delta%RDW after 96h of hospital stay independently predicted 30-day mortality (odds ratio, 1.12; 95% CI, 1.07-1.18). An increase >1% of Delta%RDW after 96h of hospital stay independently predicted both 30-day (odds ratio, 2.86; 95% CI, 1.67-4.97) and 60-day (odds ratio, 3.06; 95% CI, 1.89-4.96) mortality. A similar trend was observed for DeltaRDW, since an increase after 96h of hospital stay was associated with a nearly 4-fold higher 30-day mortality (odds ratio, 3.65; 95% CI, 2.02-6.15). CONCLUSION: Despite it remains unclear whether RDW is a real risk factor or an epiphenomenon in ADHF, these results suggest that more aggressive management may be advisable in ADHF patients with increasing anisocytosis during the first days of hospitalization.

Red blood cell population dynamics.

Hematology analyzers provide a static snapshot of the circulating population of red blood cells (RBCs). The RBC population is rapidly changing, with more than 2 million RBCs turning over every second in the typical healthy adult. The static snapshot provided by the complete blood count does not capture many of the dynamic aspects of this population, such as the rate of RBC maturation and the rate of RBC turnover. By integrating basic science with hematology analyzer measurements, it is possible to estimate the rates of these dynamic processes, yielding new insights into human physiology, with potential diagnostic application.

Relation between changes in red cell distribution width and clinical outcomes in acute decompensated heart failure.

BACKGROUND: Increased red blood cell distribution (RDW) has been associated with adverse outcomes in patients with heart failure. We studied the association between baseline RDW and changes in RDW during hospital course with clinical outcomes in acute decompensated heart failure (ADHF) patients. METHODS AND RESULTS: We prospectively studied 614 patients with ADHF. Baseline RDW and RDW change during hospital course were determined. The relationship between RDW and clinical outcomes after hospital discharge was tested using Cox regression models, adjusting for clinical characteristics, echocardiographic findings and brain natriuretic peptide levels. During follow up (1 year), 286 patients (46.6%) died and 84 were readmitted for ADHF (13.7%). Median RDW was significantly higher among patients who died compared to patients who survived (15.6% interquartile range [14.5 to 17.1] vs. 14.9% mg/L interquartile range [14.1 to 16.1], P<0.0001). Compared with patients in the 1st RDW quartile, the adjusted hazard ratio [HR] for death or rehospitalization was 1.9 [95% CI 1.3-2.6] in patients in the 4th quartile. Changes in RDW during hospitalization were strongly associated with changes in mortality risk. Compared with patients with persistent normal RDW (<14.5%), the adjusted HR for mortality was 1.9 [95% CI 1.1-3.1] for patients in whom RDW increased above 14.5% during hospital course, similar to patients with persistent elevation of RDW (HR was 1.7, 95% CI 1.2-2.3). CONCLUSION: In patients hospitalized with ADHF, RDW is a strong independent predictor of greater morbidity and mortality. An increase in RDW during hospitalization also portends adverse clinical outcome.

Adjustment of cerebrospinal fluid protein for red blood cells in neonates and young infants.

OBJECTIVE: To determine the relationship between cerebrospinal fluid (CSF) red blood cell (RBC) count and CSF protein in neonates and young infants undergoing lumbar puncture. DESIGN: Cross-sectional study. SETTING: Urban tertiary care children's hospital. PATIENTS: Infants 56 days of age and younger who had a lumbar puncture in the emergency department between January 1, 2005 and July 31, 2009 were eligible for inclusion. Infants with missing laboratory data, exceedingly high CSF red blood cell counts, or conditions known to elevate CSF protein were excluded. MEASUREMENTS: Linear regression was used to determine the association between CSF RBC and CSF protein. RESULTS: Of 1986 infants, 56 days of age or younger, who underwent lumbar puncture in the emergency department during the study period, 1241 (62.5%) met inclusion criteria. The median age was 34 days (interquartile range: 19-46 days); 45% of patients were male. The median CSF RBC count was 40 cells/mm(3) (interquartile range: 2-1080 cells/mm(3)); 11.8% of patients had a CSF RBC >10,000 cells/mm(3). CSF protein increased by 1.9 mg/dL (95% confidence interval: 1.7-2.1 mg/dL) per 1000 CSF RBCs for all included patients. Restricting analysis to patients without pleocytosis yielded comparable results, as did subanalyses by age and delivery type. CONCLUSIONS: We found that CSF protein concentrations increased by approximately 2 mg/dL for every 1000 CSF RBCs. These data may assist clinicians in interpreting CSF protein concentrations in infants 56 days of age and younger in the context of traumatic lumbar punctures.

Hemoglobin concentration variations over time in general medical inpatients.

BACKGROUND: A decrease in hemoglobin concentration [Hb] with no apparent cause is frequently observed in critically ill patients. Scarce information is available about this situation in general ward-admitted patients (GWAP). OBJECTIVES: To describe [Hb] variation with no obvious cause in GWAP, and to estimate the prevalence and predictors of patients with [Hb] decreases > or =1.5 g/dL. DESIGN, SETTING AND PATIENTS: Prospective, observational study in internal medicine GWAP, carried out at two teaching hospitals in Buenos Aires, Argentina. Patients with a history of, or admitted for diseases associated with decreases in [Hb], as well as those with length of stay less than three days, were excluded. MEASUREMENTS: Upon hospitalization, complete personal and clinical data were recorded. Furthermore, Katz index, APACHE II acute physiology score (APS) and Charlson score were calculated. [Hb] and hematocrit (HCT) were also assessed during hospitalization. RESULTS: A total of 338 patients were evaluated, 131 were included. A mean [Hb] decrease of 0.71 g/dL was observed between admission and discharge (P < 0.001; 95% CI, 0.47-0.97). Forty-five percent of the included patients had decreases in [Hb] > or = 1.5 g/dL. This was associated with a higher APS, a higher [Hb] at admission, and a discharge diagnosis of infectious or gastrointestinal disease. No bleeding episodes were observed. CONCLUSIONS: An [Hb] decrease was frequently observed during GWAP hospitalization with no evident blood loss. Even though this decrease has multiple causes, the severity of the acute illness seems to play a major role.