Regular hot baths could alleviate common circulatory disease

A regular soak in a hot bath could help to improve a common painful circulatory disease, with this strategy being studied by researchers at Manchester Metropolitan University, thanks to funding from the British Heart Foundation.

The team behind the project are investigating whether immersion in hot water may relieve the symptoms of peripheral artery disease, which affects one in five people over the age of 60 in the UK to some degree.

Researchers are hosting regular hot tub sessions to test out the heat therapy – submerging people up to their shoulders in 40C water for an average of around 40 minutes.

Peripheral artery disease (PAD) is a condition where the arteries carrying blood from the heart are narrowed by a build-up of fatty material. It usually affects arteries in the legs, causing leg pain when walking even short distances.

Frequent heat therapy – such as a bath or hot tub session – can restore some blood flow to the legs, so could improve people’s pain and help them walk further, transforming their quality of life.

Hot tub therapy

The Manchester study, called HEATPAD (HEAT Therapy for Peripheral Artery Disease), which aims to recruit 70 people and has already begun, asks volunteers to bring their swimming costumes and sit in a hot tub three times a week. They will do this for eight weeks. One of the participants, 75-year-old Ken Heywood, was able to tackle his ‘Everest’ – a steep hill in his local park – after taking part.

He said: “This study really did feel as if it worked for me, to reduce my pain and extend the distance I could walk, and I hope it’s proven to be effective, so heat therapy might be available to more people.”

Amy Harwood, professor in clinical exercise physiology at Manchester Metropolitan University Institute of Sport, leads the project, with co-supervision provided by Dr Tom Cullen from the University of Hull.

Professor Harwood said: “People with PAD are often advised to exercise to increase the blood flow to their legs. But the pain they experience can make walking and exercise less than enjoyable.

“If a hot tub or bath can provide similar benefits to exercise, then that could be much more pleasurable for people. We hope we will find evidence that it can relieve the pain of PAD, and improve people’s quality of life.”

People with PAD who are considering changing their bathing schedule should consult their GP, as being in hot water for long periods can cause blood pressure to drop and lead to dizziness. Many people with PAD also have cardiovascular disease, making this more of a risk.

Researchers will closely monitor the blood pressure of people in the new research project along with feelings of dizziness. However they hope to find a significant increase in people’s mobility as a result of the heat therapy.

Increase independence

Some people with PAD can manage no more than 30 steps (22 metres) before they are in pain, and walk only half the length of a football pitch (59 metres) before they have to stop. Being able to walk further could increase independence and greatly improve their quality of life.

In order to cool down, when you are in a hot bath or hot tub, heat is carried in your blood to the surface of the skin, so it can escape from the body. The blood vessels expand to do this, increasing blood flow. This may relieve the symptoms of PAD, because more oxygen-rich blood reaches the leg muscles.

The team will measure how far people can walk before and after eight weeks of regular bathing, as well as changes in leg and foot pain, and discomfort from pins and needles, cold feet and ulcers caused by a lack of blood flow.

The project volunteers will report if everyday tasks like washing and dressing or doing housework, become easier. They will fill out questionnaires on limitations doing activities like sports and socialising, feelings of anxiety and depression, and PAD-related fears about becoming housebound or losing a limb.

Researchers hope these measures may improve following regular hot tub sessions.

Mr Adam Haque, project co-Supervisor, Vascular Surgeon, Manchester Royal Infirmary, part of MFT, and British Heart Foundation Centre of Research Excellence Fellow at the University of Manchester, said: “Peripheral artery disease remains a major unmet clinical need, and has a huge impact on patients’ quality of life, particularly those who are unable to engage with conventional exercise therapy. This study represents an important step in evaluating novel, patient-friendly approaches that could enhance blood flow, reduce symptoms, and ultimately improve patients’ lives.”

William Carey, a PhD candidate who is running the research project from the Department of Sport and Exercise Sciences, within the Institute of Sport at Manchester Metropolitan University, said: “Hot tubs can be expensive, but baths are easier to use in everyday life.

“If we find that regular 40C baths can alleviate the symptoms of PAD, that would give us another option to offer people. It is important because many people advised to exercise have disabling pain, lack of facilities and low motivation to do physical activity. An alternative is greatly needed.”

The study is recruiting people aged 18 and over, who have PAD and intermittent claudication, and have received treatment within Manchester University NHS Foundation Trust.

Intermittent claudication, the main symptom of PAD, is the medical term for pain in the legs when walking which goes away with rest.

At least 400,000 people in the UK have been diagnosed with PAD.