Characteristics of obese patients admitted in a department of pneumology with acute hypercapnic respiratory failure (AHRF): an observational study in a north African population

Abstract

<b>Background:</b> Obesity hypoventilation syndrome (OHS) still remains an under-recognized and underappreciated cause of AHRF, which can result in misdiagnosis with delayed or inappropriate treatment. <b>Objectives:</b> to study the clinical pattern, the non-invasive ventilatory support, and the short- and long-term outcomes of patients with OHS admitted in ward with AHRF. <b>Methods:</b> Retrospective cohort study including all adults with OHS aged ≥ 18-year-old, admitted in a 90-bed-ward, for AHRF. <b>Results:</b> 44 patients were included and (34.1%) were diagnosed with malignant OHS. Coexisting OSAHS was found in 81,8%. The mean admission BMI was 41.1±6.8 Kg/m2. Patients with malignant OHS had a significantly higher rate of heart failure (p&lt;0.001), CRI (p=0.04), and dyslipidemia (p=0.04). 77.3 % were misdiagnosed as asthma exacerbation (n=4, 4.9.1%), and/or heart failure (n=29, 65.9%). BIPAP was very highly effective to treat AHRF, with only 2.27% of patients failing the modality. Median overall duration of ventilation was 9 hours per day, and was significantly longer in patients with malignant OHS (p=0.01). The probability of survival was 90% at 12 months, while the probability of readmission for a new episode of AHRF was 56% at 6 months. No factor was independently associated with a higher risk for readmission. <b>Conclusion:</b> OHS is a life-threatening event which can be successfully and safely treated with BIPAP, with a low long-term mortality even in patients with malignant OHS.