Introduction

Medically unexplained symptoms, also described as persistent physical symptoms, are those where no distinct physical cause can be found. These symptoms are varied and can include abdominal pain, body aches, fatigue, and headaches. They are common, with approximately 1 in 4 patients presenting to general practice with symptoms that cannot be explained.¹

These patients will often undergo a wide range of tests across multiple medical specialties to reassure both the patients and the doctors. This process can be frustrating and exhausting for patients, as well as costly to the National Health Service.^2,3

It is therefore important to consider the patient as a whole and consider the biological, psychological and social factors which may contribute to these symptoms. This is referred to as biopsychosocial factors and considers the impact of genetics, stress, relationships and finances on health. 

Approximately one third of patients with 4-5 medically unexplained symptoms have anxiety or depression.⁴ This number rises as the number of medically unexplained symptoms increases. This can lead to a chicken and egg type cycle, where the unexplained symptoms can cause anxiety and low mood, which can further worsen presenting symptoms.⁵ The symptoms are real and are not to be confused with factitious disorders. Factitious disorders are mental health conditions, where people will falsify symptoms or purposefully produce symptoms. 

Due to the variety of causes, medically unexplained symptoms are treated in a variety of ways including self-help, talking therapies and medication. Please continue reading for more information on the symptoms, risk factors and treatment of medically unexplained symptoms.

Symptoms

Symptoms can be varied and can affect many different parts of the body. Common symptoms include:

• Abdominal pain
• Muscle aches
• Fatigue
• Palpitations
• Headaches 

These symptoms can be associated with a large variety of diseases that have a specific physical cause and it is important to rule these out with appropriate examination and tests. For example, fatigue could be due to anaemia, a thyroid problem, or depression. The severity of the symptoms can range from mild to severe, with some impacting everyday life.^2,5

Pain syndromes

Sometimes symptoms can be clustered into syndromes such as irritable bowel syndrome, fibromyalgia, and chronic fatigue syndrome. Syndromes are groups of symptoms that typically occur together, but the exact cause may be unknown. 

For example, irritable bowel syndrome (IBS) is a common condition that affects around 1 in 5 individuals.⁶ IBS is characterised by abdominal pain with constipation or diarrhoea and is thought to be due to multiple causes. Symptoms can be worsened by certain triggers such as stress, spicy or fatty foods, and caffeinated drinks such as coffee.

The diagnosis is made through a diagnosis of exclusion method based on the cluster of symptoms, rather than a specific physical test to prove the diagnosis.⁷ The treatment of IBS focuses on both lifestyle changes and medications. For example, avoiding fatty and spicy foods if they trigger your IBS symptoms and taking laxatives for constipation.

Another example of a poorly explained syndrome is fibromyalgia. Fibromyalgia is a collection of symptoms that includes widespread pain, stiffness, and trouble concentrating. Again, there is no specific test to diagnose fibromyalgia, so instead other tests will be done to rule out other conditions that have similar symptoms. The symptoms and treatment vary from person to person, but a combination of talking therapies and medication is often useful.⁸ 

Risk factors

Certain risk factors have been identified for medically unexplained symptoms, these include:

• Childhood trauma 
• Witnessing parental ill health as a child
• Presence of additional chronic conditions
• Psychological factors^5,9

Those with another physical condition have an increased risk of medically unexplained symptoms. For example, around 1 in 5 of those with non-epileptic seizures also have a diagnosis of epilepsy.⁹ Non-epileptic seizures are seizures that are not caused by abnormal brain activity, and the exact cause may be medically unexplained. 

Psychological factors include catastrophising, rumination, and health anxiety. Catastrophising is immediately thinking about the worst case scenarios, for example: thinking a simple headache must be due to a brain tumour. These traits can lead to individuals focusing more on their symptoms which can make them worse.⁵

Additionally, there may be a trigger to the development of medically unexplained symptoms. Triggers can be physical or psychological and can include infections, stress or a co-existing physical illness.⁵

Diagnosis

A GP will start by asking questions to establish the nature of the symptoms, such as the site, onset, timing, and severity. It is important to understand if there are any triggers to the symptoms and if there is anything that relieves the symptoms.⁵ It may be useful to keep a symptom diary to recognise any patterns in symptom occurrence with certain food or stress - and the GP might recommend that this diary is continued. A GP should also discuss how these symptoms impact your daily life and if they affect your mood.

As with many medical conditions, a physical examination and blood test may be required to look for a diagnosis. For instance, diabetes and thyroid conditions often present with vague symptoms and are commonly missed without blood tests.⁹ It may be necessary for a GP to refer you to secondary care for specialised investigations such as a scan, or a review by a specialised consultant.

Treatment

As the symptoms are multifactorial, it is important to take a broad approach to treatment, focusing on both symptom control and psychological support.

The key treatment areas include:

Self-help

As previously mentioned, it can be useful to keep a symptom diary to try and recognise when the symptoms occur and if there are any triggers. Reflect on your recent social situation and whether there might be any stressors contributing to your symptoms. It can be useful to talk about these stressors to friends, family or professionals. Additionally, keeping physically active and eating a balanced diet can improve symptoms due to their beneficial effect on mood and stress.^1,10

Talking therapies

Depending on the nature of the symptoms, talking therapy may be useful for medically unexplained symptoms. This allows you to discuss triggers of the symptoms and the impact on day-to-day life. A common talking therapy is called Cognitive Behavioural Therapy (CBT), this technique helps you understand, reflect and reframe your mindset on negative thought cycles. This is shown to be effective for medically unexplained symptoms such as pain, fatigue and anxiety, but may not be effective in all cases.^10,11

Medication

Antidepressants can be useful in some cases of medically unexplained symptoms. As well as helping individuals with underlying anxiety and depression, antidepressants may help with chronic pain.¹⁰ As with all medications, antidepressants can have side effects such as nausea, shaking, and headaches, and should be discussed with a doctor before use.

Follow up

Patients with medically unexplained symptoms can often be bounced around from medical specialties only to find there is no physical cause. This can lead to discontinuity of care and patients feeling hopeless. It is therefore important that their GP can be a key figure for continued support throughout. 

Impact 

Many patients with medically unexplained symptoms feel their concerns are not taken seriously and lead to feelings of hopelessness.^3,11 This is especially common in patients from ethnic minorities, where barriers in communication can lead to feeling misunderstood. It can be extremely frustrating not understanding the cause of the symptoms, especially when they are having a large impact on day-to-day life. 

Healthcare professionals can also feel frustrated with medically unexplained symptoms due to feelings of uncertainty and lack of control.^3,11 Furthermore, healthcare professionals report poor understanding of medically unexplained symptoms due to lack of teaching on the topic and negative perceptions in both undergraduate and postgraduate medical education. This results in healthcare professionals requesting more tests to ensure they do not miss anything. These tests may be counterproductive and lead to unnecessary over-treatment.

It is therefore essential that doctors and patients work together to understand the biopsychosocial factors that may be impacting their symptoms. Good communication and follow up can leave patients feeling reassured they are receiving the correct treatment.

Summary 

Medically unexplained symptoms are symptoms where the exact cause is poorly understood but thought to be due to biological, social and psychological factors. Symptoms are common and varied, including abdominal pain, fatigue and heart palpitations. They may be part of a recognised syndrome such as irritable bowel syndrome and fibromyalgia. Symptoms may develop following a trigger, such as an acute illness or life event. A thorough history and examination can help healthcare professionals rule out other medical conditions to guide treatment plans. The majority of people will make good progress with treatment and 50-75% will improve over one year.⁴ Treatment should be patient-centred and commonly includes stress-relieving techniques such as exercise and talking therapy.

Medically unexplained symptoms can be incredibly frustrating for patients and lead to feelings of hopelessness. Patients may feel misunderstood or that no one believes their symptoms. Therefore, increased education on medically unexplained symptoms would be beneficial to reduce stigma and ensure patients feel listened to. Further education for medical professionals will help reduce anxiety and increase patient reassurance.