Sex differences in survival of oxygen-dependent patients with chronic obstructive pulmonary disease

Maria Christina L Machado, Jerry A. Krishnan, A (Sonia) Buist, Andrew L. Bilderback, Guilherme P. Fazolo, Michelle G. Santarosa, Fernando Queiroga, William M. Vollmer

Research output: Contribution to journalArticle

78 Citations (Scopus)

Abstract

Rationale: Chronic obstructive pulmonary disease (COPD) is a leading cause of death worldwide. The prevalence of COPD is rising among women and is approaching that of men, but it is not known if sex affects survival. Objectives: To measure the survival differences between men and women with oxygen-dependent COPD. Methods: We conducted a 7-yr prospective cohort study of 435 outpatients with COPD (184 women, 251 men) referred for long-term oxygen therapy (LTOT) at two respiratory clinics in Sao Paulo, Brazil. Baseline data were collected on enrollment into oxygen therapy, when patients were clinically stable. Measurements: We examined the effect of sex on survival using Kaplan-Meier survival curves, and then used Cox proportional hazards models to control for potential confounders. Main Results: In unadjusted analyses, we observed a nonsignificant trend toward increased mortality for women (hazard ratio, 1.28; 95% confidence interval, 0.98-1.68; p = 0.07). After accounting for potential confounders (age, pack-years smoked, PaO2, FEV 1, body mass index), females were at a significantly higher risk of death (hazard ratio, 1.54; 95% confidence interval, 1.15-2.07; p = 0.004). Other independent predictors of death were lower PaO2 (p = 0.001) and lower body mass index (p <0.05). Conclusions: Among patients with COPD on LTOT, women were more likely to die than men.

Original languageEnglish (US)
Pages (from-to)524-529
Number of pages6
JournalAmerican Journal of Respiratory and Critical Care Medicine
Volume174
Issue number5
DOIs
StatePublished - Sep 1 2006
Externally publishedYes

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Sex Characteristics
Chronic Obstructive Pulmonary Disease
Oxygen
Survival
Body Mass Index
Confidence Intervals
Kaplan-Meier Estimate
Proportional Hazards Models
Brazil
Cause of Death
Cohort Studies
Outpatients
Therapeutics
Prospective Studies
Mortality

Keywords

  • Chronic obstructive pulmonary disease, hypoxemic
  • Sex differences
  • Survival

ASJC Scopus subject areas

  • Pulmonary and Respiratory Medicine

Cite this

Sex differences in survival of oxygen-dependent patients with chronic obstructive pulmonary disease. / Machado, Maria Christina L; Krishnan, Jerry A.; Buist, A (Sonia); Bilderback, Andrew L.; Fazolo, Guilherme P.; Santarosa, Michelle G.; Queiroga, Fernando; Vollmer, William M.

In: American Journal of Respiratory and Critical Care Medicine, Vol. 174, No. 5, 01.09.2006, p. 524-529.

Research output: Contribution to journalArticle

Machado, Maria Christina L ; Krishnan, Jerry A. ; Buist, A (Sonia) ; Bilderback, Andrew L. ; Fazolo, Guilherme P. ; Santarosa, Michelle G. ; Queiroga, Fernando ; Vollmer, William M. / Sex differences in survival of oxygen-dependent patients with chronic obstructive pulmonary disease. In: American Journal of Respiratory and Critical Care Medicine. 2006 ; Vol. 174, No. 5. pp. 524-529.
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