Causes of long-term breathlessness

Reasons for long-term breathlessness include:

  • obesity or being unfit
  • poorly controlled asthma
  • chronic obstructive pulmonary disease (COPD) – permanent damage to the lungs usually caused by years of smoking
  • anaemia – a low level of oxygen in the blood caused by a lack of red blood cells or haemoglobin (the part of red blood cells that carries oxygen)
  • heart failure – when your heart is having trouble pumping enough blood around your body, usually because the heart muscle has become too weak or stiff to work properly
  • a problem with your heart rate or rhythm, such as atrial fibrillation (an irregular and fast heart rate) or supraventricular tachycardia (regular and fast heart rate)

More unusual causes of long-term breathlessness are:

  • a lung condition where the airways are abnormally widened and you have a persistent phlegmy cough (bronchiectasis
  • a recurrent blockage in a blood vessel in the lung (pulmonary embolism
  • partial collapse of your lung caused by lung cancer
  • a collection of fluid next to the lung (pleural effusion)
  • narrowing of the main heart valve, restricting blood flow to the rest of the body
  • frequent panic attacks, which can cause you to hyperventilate (take rapid or deep breaths)