Tingling, tingling, itching…that’s what people with Restless Leg Syndrome (RLS) feel. They are forced to move in order to relieve their legs. RLS affects the quality of life and sleep of those affected. Indeed, these symptoms occur mainly in the evening or at night, de facto, they strongly impact the quality of sleep and the mental health of patients. A team from Montpellier has quantified depressive disorders and the frequency of suicidal thoughts in people suffering from RLS and measured how appropriate treatment improves both sensorimotor symptoms and the mental health of patients.
Restless Leg Syndrome: What is it?
Restless Leg Syndrome (SJSR) is translated by very unpleasant sensations in the legs requiring them to be moved regularly to relieve them. It usually begins in adulthood and mainly affects women. It is estimated that 2 to 3% of the population would be affected chronically and 6 to 7% occasionally. Symptoms occur mostly in the extremities of the legs and sometimes in the arms (in 20% of cases). Patients experience tingling, tingling, burning, itching and even a feeling of “electric shock”. These sensations induce an urgent and irresistible urge to move the limbs involved.
The underlying mechanisms are still poorly understood, but two elements seem to come into play: an iron deficiency and/or a lack of dopamine, a neurotransmitter involved in motor functions, the reward circuit and other associated cognitive functions. These elements can be triggers in the event of a genetic predisposition, the onset of a disease or the taking of certain medications.
Since the symptoms of RLS occur mainly at rest in the evening or at night, they are a major cause of sleeping troubles with frequent awakenings, insomnia and inability to fall back to sleep. The consequences can be very serious, especially on the mental health of patients.
Restless Leg Syndrome Deteriorates Patients’ Mental Health
Previous studies suggest that people with RLS have a greater risk of presenting with depressive disorders or to have suicidal thoughtsespecially those who suffer from insomnia. A study, conducted by researchers from Montpellier in collaboration with the National Narcolepsy Hypersomnia Reference Center, quantified the frequency of these depressive symptoms and whether the treatment of RLS made it possible to resolve these complaints.
To carry out this work, the authors included 549 patients with untreated RLS and 549 other people, serving as a control group, without syndrome and matched in age, sex and level of education. The two groups first carried out standardized evaluations including a questionnaire measuring the existence of depressive disorders or suicidal thoughts, an evaluation of the quality of their sleep and another questionnaire evaluating the presence of impulsivity disorders. The questionnaires were completed by a consultation with a neuropsychologist, in order to validate them.
The results of the study show that:
- 79% of those affected by RLS also suffered from insomnia compared to 8.3% in the control group;
- The frequency of depressive disorders is nearly 10 times greater in people with RLS compared to the control group;
- The frequency of suicidal thoughts is 3 times higher in people with RLS;
- In the group suffering from RLS, the study establishes that the risk of suicide is associated with the presence of a depressive disorder, an impulsivity disorder and the severity of the syndrome.
The patients followed a personalized treatment of their RLS for 1 year. The reassessment of depressive and sleep disorders after one year of treatment shows a marked improvement in these symptoms but no effect on the frequency of suicidal thoughts.
Factors favoring depressive disorders in case of restless legs syndrome
This study also made it possible to identify factors favoring the risk of suicide in people with RLS. The womenthe youththose suffering frominsomnia and those with a tendency toimpulsiveness, lack of perseverance or premeditation of their actions are the most vulnerable. These behaviors highlighted are linked to the action of dopamine, a neurotransmitter involved in the mechanisms responsible for RLS.
The results of this work highlight the importance of detecting depressive symptoms in routine clinical practice and monitor their evolution after treatment for RLS.
Alexia F., Doctor in Neurosciences
Sources
– The mental burden of restless leg syndrome. inserm.fr. Accessed February 18, 2022.
– Restless legs syndrome: definition and causes. ameli.fr. Accessed February 18, 2022.