Prognostic value of the hematocrit in patients with severe COPD receiving long-term oxygen therapy

BACKGROUND: Although traditionally associated with polycythemia, COPD has a systemic inflammatory component that could interfere with erythropoiesis. This study describes the distribution and prognostic value of the hematocrit in patients with severe COPD receiving long-term oxygen therapy (LTOT). METHODS: A total of 2,524 patients with COPD, FEV1/vital capacity (VC) < 70%, FEV1 < 80% of predicted, and Pa(O2) < 7.3 kPa in whom a hematocrit was available at entry was identified between 1980 and 1999 in the French Association Nationale pour le Traitement à Domicile de l'Insuffisance Respiratoire chronic respiratory insufficiency and home-care database (male/female ratio, 5/1; mean +/- SD age, 68 +/- 10 years for men, and 70 +/- 10 years for women). Correlations between hematocrit, demographic data, and pulmonary function data were examined. A multivariate Cox proportional hazard regression was performed to identify prognostic factors. RESULTS: Mean hematocrit was 45.9 +/- 7.0% in men and 43.9 +/- 6.0% in women (< 39% in 12.6% of men, and < 36% in 8.2% of women) according to the World Health Organization definition of anemia. Hematocrit was negatively correlated with age (r = - 0.245) and FEV1/VC (r = - 0.068) and was positively correlated with Pa(CO2) (r = 0.161) and body mass index (r = 0.127). Multivariate analysis found hematocrit to be an independent predictor of survival, hospital admission rate, and cumulative duration of hospitalization. The 3-year survival was 24% (95% confidence interval, 16 to 33%) when the hematocrit was < 35%, and 70% (63 to 76%) when the hematocrit was > or = 55%. CONCLUSIONS: A low hematocrit is not uncommon in LTOT/COPD patients. Hematocrit is negatively associated with mortality and morbidity. Whether the association is causative or not and whether or not corrective measures are warranted remain to be determined.     

A multicentre trial of education strategies at CPAP induction in the treatment of severe sleep apnoea-hypopnoea syndrome

BACKGROUND AND PURPOSE: Compliance with continuous positive airway pressure (CPAP) treatment in obstructive sleep apnoea syndrome (OSAS) may be difficult. Patient education is important but strategies and their outcomes are not clear. PATIENTS AND METHODS: We studied the effects of four education strategies on compliance and quality of life changes with CPAP treatment in seven centres in the French ANTADIR homecare network. Patients received from prescribers either a simple oral explanation (SP) or an oral and written explanation (RP) of CPAP use. In addition, they received from homecare technicians either a single home visit (SH) at CPAP onset or repeated home visits at CPAP onset and at 1 week, 1 month and 3 months after (RH). Compliance and quality of life were evaluated at CPAP onset, and at 3, 6 and 12 months after initiation of treatment. RESULTS: One hundred twelve patients with severe OSAS (mean age 58+/-11 year, apnoea-hypopnoea index 58+/-25/h) were allocated randomly to groups (SP+SH; SP+RH; RP+SH; RP+RH) with no initial differences. Quality of life, evaluated by the generic SF-36 questionnaire, improved in the combined emotional domains. Compliance was over 5h in all four education groups. These effects were sustained over 12 months and were not different between the four groups. We conclude that standard education strategies for CPAP induction in France are sufficient for good compliance and improved quality of life with CPAP. Education with reinforced input should be focussed on identified subgroups prone to problems.     

Evaluation of autoCPAP devices in home treatment of sleep apnea/hypopnea syndrome

BACKGROUND AND PURPOSE: Quality of life (QOL) and sleepiness for patients with sleep apnea/hypopnea syndrome (SAHS) might improve with continuous positive airway pressure devices working in auto-adjust mode (autoCPAP) by allowing pressure modulations following patient needs. Clinical comparisons between devices driven by different algorithms are needed. METHODS: We compared the clinical effectiveness of fixed pressure CPAP and four different autoCPAP devices by assessing compliance and QOL (36-item short-form health survey [SF-36]). SAHS patients were randomly allocated to five groups. Polysomnography (PSG) was performed to titrate the effective pressure in the constant CPAP group and evaluate residual apnea/hypopnea index (AHI) under autoCPAP. Follow-up consisted of clinical visits at three and six months by homecare technicians who assessed compliance, symptom scores and SF-36 scores. A laboratory-based PSG using the same CPAP/autoCPAP device as at home was performed at six months. RESULTS: Eighty-three patients (mean age 56+/-10 yrs) with mean body mass index (BMI) 30.8+/-5.3 kg/m(2) and severe SAHS (mean AHI: 52.3+/-17.8/h) were included. There were no differences in clinical symptoms or QOL scores, and similar clinical and PSG improvements were seen in all groups. CPAP use was >5 h per night, without any significant difference between groups. CONCLUSIONS: AutoCPAP is equally as effective as fixed CPAP for long-term home treatment in severe SAHS patients.