Some welfare entitlement applications are based on something called functionality (this is what you can and can’t do on a day to day basis). The World Health Organisation (WHO) functional class system was created to define the severity of an individual’s symptoms and how they impact on day-to-day activities, so understanding these definitions may be helpful when thinking about completing your disability benefits applications.
“Patients with Pulmonary Hypertension but without any resulting limitation of physical activity. Ordinary physical activity does not cause; breathlessness, fatigue (tiredness), or activities that can cause chest pain, dizziness or even black outs.”
So, this would describe you if you do not suffer from the above symptoms when doing ‘ordinary physical activity’ – such as climbing a flight of stairs, doing the dishes, bathing and cooking (not going for a run or going to the gym).
“Patients with Pulmonary Hypertension resulting in slight limitation of physical activity. They are comfortable at rest. Ordinary physical activity causes undue breathlessness, fatigue (tiredness), or activities that can cause chest pain, dizziness or even black outs.”
This would be one of the classes that the majority of patients with PH would fall into. This would describe you if when ‘at rest’ (sitting, laying down or standing still) you have no symptoms of breathlessness etc., however when carrying out ‘ordinary physical activity’ (for example climbing a flight of stairs, shopping, or making the bed) you do suffer from any of the above symptoms.
“Patients with Pulmonary Hypertension resulting in marked limitation of physical activity. They are comfortable at rest. Less than ordinary activity causes undue breathlessness, fatigue (tiredness), or activities that can cause chest pain, dizziness or even black outs.”
This, like class 2, is the other class that the majority of patients with PH would fall into. This would describe you if when ‘at rest’ (sitting, laying down or standing still) you have no symptoms of breathlessness and so on, but can have difficulty doing general day-today activities such as household chores. You may have to take breaks while carrying out daily living activities (climbing a flight of stairs, walking to the shops and so on)
“Patients with pulmonary hypertension with inability to carry out any physical activity without symptoms. These patients manifest signs of right heart failure, breathlessness and /or fatigue, which may even be present at rest. Discomfort is increased by any physical activity.”
This is the most severe class of PH. It describes how the patient may suffer from symptoms even at rest (for example when sitting down) and will suffer from severe symptoms whilst doing any activity, no matter what it is.
The information on this page was reviewed and updated in September 2023
