TABLE 1

Variables that contribute to elevated anxiety in patients with chronic obstructive pulmonary disease

Demographic and physiological
  •  Reduced lung function [4, 8]

  •  Elevated level of dyspnoea [4, 8]

  •  Lower socioeconomic status [5]

  •  Hyperventilation [6]

  •  Female sex [1, 5]

  •  Sleep disturbance and sleep apnoea [6–8]

Behavioural
  •  Lower body mass index [5]

  •  Active smoking [5, 8]

  •  Tobacco addiction [8]

Social
  •  Frustration dependency on caregivers [5, 8]

  •  Reduced exercise tolerance [1, 4, 5]

  •  Anger, loss of interest in social interaction [1, 4, 5]

  •  Social phobia [1, 8]

  •  Fear avoidance [1, 4]

  •  Panic [1, 4, 8]

  •  Stigma [5, 8]

  •  Severe depression [5]