title: Prevalence of different comorbidities in COPD patients by gender and GOLD stage.
abstract: BACKGROUND
  Several comorbidities frequently affect COPD progression. Aim of the study was to assess the prevalence of main comorbidities by gender and disease severity in a cohort of COPD patients referring for the first time to a specialist institution.
  
  
  METHODS
  The study was a non-interventional, cross-sectional investigation carried out via automatic and anonymous selection from the institutional data base over the period 2012-2015. Inclusion criteria were: subjects of both sex aged ≥40 years; diagnosis of COPD according to GOLD guidelines 2014; the availability of a complete clinical record file. Variables collected were: lung function; smoking history; BMI; the Charlson Comorbidity Index (CCI); number and kind of comorbidities for each patient.
  
  
  RESULTS
  At least one comorbidity of clinical relevance was found in 78.6 % of patients, but at least two in 68.8 %, and three or more were found in 47.9 % of subjects. Mean CCI was 3.4 ± 1.6sd. The overall prevalence was 2.6 comorbidities per patient, but 2.5 in males, and 3.0 in females, respectively (p < 0.05). Cardio-vascular disorders were the most frequent, but significantly more frequent in males (44.7 vs 30.7 %, respectively), while the metabolic, the digestive and the osteo-articular disorders were prevailing in females (12.4 vs 9.2; 14.2 vs 4.8, and 6.0 vs 3.8, respectively). In particular, chronic cor pumonale and arrhythmias mainly prevailed in men and congestive heart failure in females, while arterial hypertension resulted equally distributed. As concerning respiratory disorders, pneumonia, pleural effusions and chronic respiratory failure were more frequently found in men, while bronchiectasis and asthma-COPD overlap syndrome (ACOS) in females. Anaemia, gall bladder stones, osteoporosis and spontaneous fractures mostly prevailed in females, while gastric disorders of inflammatory origin and arthrosis were more frequent in males. Cognition disorders, dementia and signs of degenerative brain disorders were more frequently found in men, while depression in females. Finally, lung cancer was at the first place in men, but at the second in females.
  
  
  CONCLUSIONS
  All comorbidities increased their prevalence progressively up to the last stage of COPD severity, except the cardio-vascular and the metabolic ones which dropped in the IV GOLD stage, presumably due to the high mortality rate in this severe COPD stage. The gender-dependency of comorbidities was confirmed in general terms, even if lung cancer proved a dramatic increase almost independently of sex.
authors.affiliation: National Centre for Respiratory Pharmacoeconomics and Pharmacoepidemiology, CESFAR, Verona, Italy ; CEMS, Specialist Medical Centre, Verona, Italy.
authors.forename: R W
authors.initials: RW
authors.lastname: Dal Negro
authors.affiliation: Research & Clinical Governance, Verona, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Bonadiman
authors.affiliation: Research & Clinical Governance, Verona, Italy.
authors.forename: P
authors.initials: P
authors.lastname: Turco
keywords: COPD; Comorbidities; GOLD severity; Gender