Hypercapnia in Overlap Syndrome: Possible Determinant Factors

Onofrio Resta; Maria Pia Foschino Barbaro; Caterina Brindicci; Maria Cristina Nocerino; Gennaro Caratozzolo; Monica Carbonara

doi:10.1055/s-2002-23151

Sleep Breath 2002; 06(1): 011-018
DOI: 10.1055/s-2002-23151

ORIGINAL ARTICLE

Hypercapnia in Overlap Syndrome: Possible Determinant Factors

Onofrio Resta¹ , Maria Pia Foschino Barbaro² , Caterina Brindicci¹ , Maria Cristina Nocerino¹ , Gennaro Caratozzolo¹ , Monica Carbonara³

¹Centre of Sleep Breathing Disorders, Department of Clinical Methodology and Medical Surgery Technology, University of Bari, Bari, Italy
²Department of Respiratory Disease, University of Foggia, Foggia, Italy
³Public and Internal Medicine Department, University of Bari, Bari, Italy

Abstract

ABSTRACT

We retrospectively evaluated data from 213 consecutive patients; 152 were affected by obstructive sleep apnea (OSA), 29 had OSA associated with chronic obstructive pulmonary disease (COPD), also known as overlap syndrome, and 32 had COPD. Patients with obesity-hypoventilation syndrome were not included. The aims of the study were to evaluate the anthropometric, pulmonary, and polysomnographic characteristics of patients affected by overlap syndrome compared to ``simple'' OSA and to COPD subjects and to analyze the determinants of hypercapnia in overlap syndrome. In the comparison between overlap and OSA patients, the overlap group had a significantly higher PaCO₂ (44.59 vs. 39.22 mm Hg; p < 0.01), in the presence of a similar AHI (40.46 vs. 41.59/h). Comparing overlap to COPD patients, overlap showed a significantly higher PaCO₂ value (44.59 vs. 39.63 mm Hg; p < 0.005) and had significantly less severe obstructive impairment (FEV 162.93 vs. 47.31%; FEV₁/FVC ratio 66.71 vs. 59.25%; p < 0.005). Anthropometric, pulmonary function, and polysomnographic data did not differ between normo- and hypercapnic overlap patients. The best model (stepwise multiple regression analysis) for predicting PaCO₂ in overlap patients showed r2 value 0.65: PaO₂ contributed to 38%, FEV₁ to 15%, and weight to 12%. In conclusion, the occurrence of hypercapnia in overlap patients is only partially explained by the combination of overweight and reduced respiratory function, supporting the hypothesis of a multifactorial genesis.

KEYWORD

COPD - obesity hypoventilation - obstructive sleep apnea - overlap syndrome

Volltext

Referenzen

REFERENCES

1 Weitzenblum E, Chaouat A, Kessler R, Oswald M, Appril A, Krieger J. Daytime hypoventilation in obstructive sleep apnoea syndrome. Sleep Med Rev . 1999; 1 79-93
2 Bradley T D, Rutheford R, Lue F. Role of diffuse airway obstruction in the hypercapnia of obstructive sleep apnoea. Am Rev Respir Dis . 1986; 134 920-924
3 Krieger J, Sforza E, Appril M. Pulmonary hypertension, hypoxemia and hypercapnia in obstructive sleep apnoea syndrome. Chest . 1989; 96 729-737
4 Resta O, Foschino Barbaro P M, Bonfitto P G. Hypercapnia in obstructive sleep apnea syndrome. Netherlands J Med . 2000; 56 215-222
5 Chaouat A, Weitzenblum E, Krieger J, Oswald M, Kessler R. Pulmonary hemodynamics in the obstructive sleep apnoea syndrome: results in 220 consecutive patients. Chest . 1996; 109 380-386
6 Siafakas N M, Vermeire P, Pride N B, for the Task Force. European Respiratory Society (ERS) Consensus Statement, et al. Optimal assessment and management of chronic obstructive pulmonary disease (COPD). Eur Respir J . 1995; 8 1398-1420
7 Chaouat A, Weitzenblum E, Krieger J, Ifoundza T, Oswald M, Kessler R. Association of chronic obstructive pulmonary disease and sleep apnea syndrome. Am J Respir Crit Care Med . 1995; 151 82-86
8 Javahery S, Colangelo G, Lacey W, Gartside P S. Chronic hypercapnia in obstructive sleep apnea-hypopnea syndrome. Sleep . 1994; 17(5) 416-423
9 Leech J A, Onal E, Baer P, Lopata M. Determinants of hypercapnia in occlusive sleep apnoea syndrome. Chest . 1987; 92 807-813
10 Resta O, Foschino Barbaro P M, Bonfitto P. Prevalence and mechanisms of diurnal hypercapnia in a sample of morbidly obese subjects with obstructive sleep apnoea. Respir Med . 2000; 94 240-246
11 Garay S M, Rapoport D, Sorkin B, Epstein H, Feinberg I, Goldring R M. Regulation of ventilation in the obstructive sleep apnoea syndrome. Am Rev Respir Dis . 1981; 124 451-457
12 Berthon-Jones M, Sullivan C E. Time course of change in ventilatory response to CO₂ with long-term CPAP therapy for obstructive sleep apnoea. Am Rev Respir Dis . 1987; 135 144-147
13 Piper A J, Sullivan C E. Effects of short-term NIPPV in the treatment of patients with severe obstructive sleep apnea and hypercapnia. Chest . 1994; 105 434-440
14 Han F, Chen E, Wei H, He Q, Ding D, Strohl K P. Treatment effects on carbon dioxide retention in patients with obstructive sleep apnea-hypopnea syndrome. Chest . 2001; 119 1814-1819