- Date posted
- 21w
My Current Challenge:
FND has caused some major problems in my life and has made my OCD flare up horribly. Here's what it is: Disease Overview Functional neurological disorder (FND) is a medical condition in which there is a problem with the functioning of the nervous system and how the brain and body sends and/or receives signals, rather than a structural disease process such as multiple sclerosis or stroke. FND can encompass a wide variety of neurological symptoms, such as limb weakness or seizures. FND is a condition at the interface between the specialties of neurology and psychiatry. Conventional tests such as MRI brain scans and EEGs are usually normal in patients with FND. This had led, historically, to the condition being relatively neglected by both clinicians and researchers. However, it is now established that FND is a common cause of disability and distress, which may overlap with other problems such as chronic pain and fatigue. Encouraging studies support the potential reversibility of FND with specifically tailored treatments. New scientific findings are influencing how patients are diagnosed and treated, which is creating an overall change in attitude towards people with FND. Older ideas that FND is âall psychologicalâ and therefore always associated with stress or past trauma, and that the diagnosis is made only when someone has normal tests, have changed since the mid-2000s. The new understanding, including modern neuroscientific studies, has shown that FND is not a diagnosis of exclusion. It has specific clinical features of its own and is a disorder of the nervous system functioning in which many perspectives are necessary. These vary a lot from person to person. In some people, psychological factors are important; in others, they are not. Signs & Symptoms FND patients can experience a wide range and combination of symptoms that are physical, sensory and/or cognitive. The most common include: Motor dysfunction ⢠Functional limb weakness/paralysis ⢠Functional movement disorders including tremor, spasms (dystonia), jerky movements (myoclonus) and problems walking (gait disorder) ⢠Functional speech symptoms including whispering speech (dysphonia), slurred or stuttering speech Sensory dysfunction ⢠Functional sensory disturbance includes altered sensation; e.g., numbness, tingling or pain in the face, torso or limbs; this often occurs on one side of the body ⢠Functional visual symptoms including loss of vision or double vision Episodes of altered awareness ⢠Functional seizures (also called dissociative or non-epileptic) seizures, blackouts and faints: these symptoms can overlap and can look like epileptic seizures or faints (syncope) Dizziness Functional dizziness is often called persistent perceptual postural dizziness and has its own set of diagnostic criteria Cognitive Symptoms Functional cognitive symptoms include difficulties with memory, concentration or word finding difficulty where there are typical features consistent with an FND diagnosis Symptoms often fluctuate and may vary from day to day or be present all the time. Some patients with FND may experience substantial or even complete remission followed by sudden relapses of symptoms. Other physical and psychological symptoms are commonly experienced by patients with FND although they are not defined as part of the disorder. These include chronic pain, fatigue, sleep problems, bowel and bladder symptoms, anxiety, panic attacks and depression. The exact cause of FND is unknown, although ongoing research is starting to provide suggestions as to how and why it develops. Many different predisposing factors can make patients more susceptible to FND such as having another neurological condition, experiencing chronic pain, fatigue or stress. Childhood abuse, maltreatment or neglect and life stress, particularly around the time of symptom onset, is also more common in people with FND than in the general population. However, many people with FND have none of these risk factors which are also unfortunately common in all, including healthy, populations. As with most complex disorders affecting the brain, itâs likely that genetic factors play a role in the condition, but it is not a problem that someone should expect to pass on genetically. At the time FND begins, studies have shown that there may be triggering factors like a physical injury, infectious illness, vaccination, panic attack or migraine which can give someone the first experience of neurological symptoms. These symptoms normally settle down on their own. However, in FND the symptoms become âstuckâ in a âpatternâ in the nervous system. That âpatternâ is reflected in altered brain functioning. The result is a genuine and disabling problem, which the patient cannot control. The aim of treatment is to âretrain the brainâ, for example by unlearning abnormal and dysfunctional movement patterns that have developed and relearning normal movement. For seizures, the aim is to unlearn the seizure program that has become stuck in the brain, and which activates typically with very little trigger or perhaps just in response to being relaxed. One way of thinking about FND is looking at it as a bit like a âsoftwareâ problem on a computer. The âhardwareâ is not damaged but there is a problem with the âsoftwareâ and so the computer doesnât work properly. A different analogy is a piano that is not broken but is out of tune. Conventional structural MRI brain scans are usually normal in FND unless the person has another neurological condition. Special functional brain scans (fMRI) used in research, which show patterns of brain activity, are starting to provide early evidence for how the brain goes wrong in FND. fMRI scans show changes in patients with FND which look different from healthy patients without these symptoms as well as being different from healthy people pretending to have these symptoms. Functional imaging is still just a research tool and is not developed enough to be used in diagnosing individual cases of FND. Scans support what patients and researchers already know â these are genuine disorders in which there is a change in brain functioning, which is out of the control of the person with FND. Historically, FND has traditionally been viewed as an entirely psychological disorder in which repressed psychological stress or trauma gets converted into a physical symptom. This is where the term conversion disorder comes from. Psychological disorders and stressful life events, both recent and in childhood, are risk factors for developing the condition and can be relevant for some patients, but they rarely provide a full explanation for the cause of the condition and are absent in many patients. Patients do not have to be depressed, anxious or the survivor of adverse childhood experience to develop FND. Modern theories propose that FND has many causes, which vary from patient to patient. One comparison is to think about heart disease. There are lots of causes of heart disease â smoking, genetic factors, diet and even stress-related/psychological factors such as depression. Smoking may be a factor in heart disease in many people, but it is not in everyone. The same analogy can be made for FND. In some, psychological factors such as past trauma or stress at the time of symptom onset in FND are important in understanding how the brain has gone wrong. In others, the presence of a problem like migraine or a physical injury may be the most important thing. Affected populations The exact prevalence of FND is unknown. However, research suggests FND is the second most common reason for a neurological outpatient visit after headache/migraine, accounting for one sixth of diagnoses. This means FND could be as common as multiple sclerosis or Parkinsonâs disease. FND can affect anyone, at any time, although it is uncommon in children under 10. FND is 2-3 times more likely to affect females than males for most symptoms, although when patients present over the age of 50, it occurs equally in both groups. Disorders with Similar Symptoms It is common for FND to co-exist with other illnesses. FND can have similar symptoms to most other types of conditions seen in neurological practice such as multiple sclerosis, stroke and epilepsy. Some patients have another neurological disease diagnosis such as stroke and FND. A neurologist is normally required to assess which symptoms relate to FND and to monitor where required for any new symptoms. Anxiety disorders and depression can sometimes cause physical symptoms which overlap with FND symptoms. For example, panic attacks can present with symptoms such as pins and needles in the fingers or mouth and depression often causes poor concentration or fatigue. Anxiety, panic attacks and depression are common in patients with FND, but many patients do not have such problems. Other psychiatric conditions are more common in people with FND including post-traumatic stress disorder (PTSD), and emotionally unstable personality traits (often related to past trauma). There is also some emerging evidence that obsessive compulsive disorder (OCD) and autistic spectrum disorder (ASD) are more common in FND populations and might predispose individuals to developing FND symptoms. Chronic pain is also common in patients with FND including fibromyalgia, which is also related to disturbed nervous system functioning. Pain disorders are also usually associated with fatigue, sleep disturbance, and poor concentration. Migraine and chronic headaches are also common. Other functional disorders including irritable bowel syndrome or overactive bladder syndrome are more common in patients with FND. There is some newer research suggesting that joint hypermobility spectrum disorder (which includes Ehlers Danlos type 3) may be more common in people with FND as well as other functional disorders. It should be remembered, though, that in these studies around 10-30% of healthy controls also had hypermobility. It is important that new symptoms not automatically be considered related to FND and other causes are considered and investigated as appropriate.