The Significance of the Relative Lymphocyte Count as an Independent Predictor of Cardiovascular Disease in Patients with Obstructive Sleep Apnea Syndrome.

OBJECTIVE: The aim of this study was to determine whether or not relative lymphocyte count (RLC) is associated with cardiovascular disease (CVD) in patients with obstructive sleep apnea syndrome (OSAS). SUBJECTS AND METHODS: In this study, 141 patients diagnosed with OSAS using polysomnography were enrolled. Patients were classified according to the severity of OSAS as determined by the apnea-hypopnea index (AHI) and presence of CVD. Lymphocyte count and other hematological parameters at complete blood count were determined and compared between patients with and without CVD. Multivariate regression analysis was used to estimate the associated factors for presence of CVD. RESULTS: Absolute and relative lymphocyte counts were lower in the OSAS patients with CVD compared to those without CVD (mean absolute lymphocyte counts: 2.0 × 103 vs. 2.5 × 103 µl, p = 0.004, and mean RLC: 28.3 vs. 33.9%, p = 0.001, respectively). OSAS patients with CVD (14.2) had higher red cell distribution width values than the patients without CVD (13.4) (p = 0.005). Multivariate analysis identified RLC as an independent predictor of CVD in patients with OSAS (odds ratio = 0.9, 95% CI: 0.85-1.0, p = 0.042). CONCLUSION: RLC was identified as an independent predictor of CVD in patients with OSAS. Since RLC is a widely available diagnostic tool with no additional costs over the routinely performed complete blood count, it can be used for predicting CVD in patients with OSAS.

Red cell distribution width in patients with obstructive sleep apnea syndrome.

BACKGROUND: Red cell distribution width (RDW) has been shown to be associated with adverse outcomes in left-sided heart failure, pulmonary hypertension, and in patients in the ICU. However, the role of RDW is unknown in patients with obstructive sleep apnea syndrome (OSAS), especially in OSAS patients with cardiovascular diseases. METHODS: One hundred thirty-seven patients were investigated by polysomnography (PSG) for OSAS. The patients were classified as a control group or as the OSAS group according to the apnea-hypopnea index (AHI). The RDW, hemoglobin level, and mean corpuscular volume (MCV) were determined. C-reactive protein (CRP) levels were measured. RESULTS: The RDW values were higher in the OSAS group than in the controls [13.6% (12-23%) vs. 12.9% (11.7-14.5%), p=0.003]. The RDW values were higher in patients with cardiovascular diseases [13.7% (11.7-23.2%) vs. 13.2% (12-16.9%), p=0.001]. RDW ≥ 13.6% (odds ratio [OR] =1.5 [95% CI = 1.0-2.0], p = 0.014) was found to be associated with increased risk for cardiovascular disease in patients with OSAS on multivariate analysis. It was also shown that there was a significant correlation between the RDW and the AHI (r=0.272), age (r=0.362), mean SaO(2) (r=0.375), systolic pulmonary artery pressure (r=0.435), and CRP level (r=0.275) in study population. CONCLUSIONS: RDW is a newly recognized and widely available diagnostic tool with no additional cost over the routinely performed hemogram. RDW is independently associated with cardiovascular disease in patients with OSAS in our cross-sectional study.

Diagnostic value of pleural effusion ischaemia-modified albumin in patients with cardiac failure.

BACKGROUND: Ischaemia-modified albumin (IMA) is a relatively new marker of ischaemia. IMA has not been studied previously in pleural effusions due to congestive heart failure (CHF). The aim of our study was to assess the diagnostic value of IMA in the pleural fluid (PF) and serum for the identification of pleural effusion due to CHF. METHODS: The concentrations of pleural fluid and serum IMA were measured in a total of 40 patients: 10 with CHF and 30 with non-cardiac failure (10 with acute pulmonary embolism, 10 with parapneumonic effusion and 10 with malignancy). The area under the curve (AUC) quantified the overall diagnostic accuracy of the tests. RESULTS: The study demonstrated that IMA concentration was higher in both pleural fluid and serum of CHF patients compared with non-cardiac patients. PF and serum IMA demonstrated AUCs of 0.927 (95% CI: 0.844-1.00, P < 0.001), and 0.792 (95% CI: 0.653-0.930, P = 0.006), respectively, for diagnosing effusions due to CHF. The sensitivity and specificity of PF-IMA for CHF at the cut-off concentration of ≥1.0 absorbance units was 90% and 80%, respectively. Its negative predictive value (NPV) was quite high (96%). Positive correlation was found between PF-IMA concentrations and serum-IMA (r = 0.540, P < 0.001). CONCLUSIONS: Measuring IMA concentrations in serum and pleural fluid may be helpful in distinguishing pleural effusion due to a cardiac or non-cardiac aetiology.

Pulmonary atelectasis and survival in advanced non-small cell lung carcinoma.

Atelectasis was reported as a favorable prognostic sign of pulmonary carcinoma; however, the underlying mechanism in those patients is not known. In this study, we aimed to investigate prospectively the potential impact of atelectasis and/or obstructive pneumonitis (AO) on survival and the relation between atelectasis and some laboratory blood parameters. The study was conducted on 87 advanced stage non-small cell lung cancer (NSCLC) patients. Clinical and laboratory parameters of patients at first presentation were recorded, and patients were divided into two groups according to the presence of AO in thorax computed tomography (CT). Survival was calculated using Kaplan-Meier and univariate Cox's regression analyses. Laboratory parameters that might be related with prolonged survival in atelectasis were compared using chi-square, Student's t, and Mann-Whitney U tests. Of the patients, 54% had stage IV disease, and AO was detected in 48.3% of all cases. Overall median survival was 13.2 months for all cases, 10.9 months for patients without AO, and 13.9 months for patients with AO (P=0.067). Survival was significantly longer in stage III patients with AO (14.5 months versus 9.2 months, P=0.032), but not in stage IV patients. Patients with AO in stage III had significantly lower platelet counts (P=0.032) and blood sedimentation rates than did those with no AO (P=0.045). We concluded that atelectasis and/or obstructive pneumonitis was associated with prolonged survival in locally advanced NSCLC. There was also a clear association between atelectasis and/or obstructive pneumonitis and platelets and blood sedimentation rate.