Are there any links?

Is there more risk of being a parkinsonian when you have bipolar disorder and. Furthermore, conversely, is the risk of being bipolar increased when you are a parkinsonian? Moreover, Is there a link between the two pathologies. Similarly, and if this link exists, is it simply fortuitous or more installed than that? For example, Dominique Drapierprofessor of psychiatry at the University of Rennes 1 (35), set out to answer these questions, studies in support. In addition, When NEUROSCIENCES Psychiatry Neurology (JNPN) 2025he has developed the complex relationships between neuropsychiatric disorders between them ^[1].

Common characteristics

Parkinson’s disease and bipolar disorders (TB) are chronic pathologies that share several common characteristics. For example, anxiety, depression and paradoxical sleep disorders are frequent in Parkinson’s disease ^[2,3,4]. In addition, Contrary to what one might think at first. Consequently, they are not (only) the consequence of there any links? the occurrence of a chronic pathology. Therefore, “It’s more complex than that,” said Professor Dominique Drapier. For example, The proof is that they occur very early in Parkinson’s disease (MP). Furthermore, in the four to five years before the appearance of motor disturbances, and persist in the long term, he stresses. In addition, this depression – constitutive of bipolar disorders – is extremely frequent in Parkinson’s disease ^[5,6]. Nevertheless, About 25% of patients with MP will receive antidepressants and up to 20% could develop severe intensity depression. In addition, suicidal risk is important in these patients. Nevertheless, Among the risk factors to anticipate Parkinsonian patients who are more at risk of developing depression: female sex. However, family history of depressive disorders, the early beginning of neurological disease, duration of evolution, the importance of dysautonomy, motor fluctuations or the presence of certain genetic mutations (LRRK2), lists the speaker.

Identify Parkinsonian there any links? patients at risk

Can we be more precise on the identification of these patients? Is there a particular clinical presentation? “Epidemiological data show that it has more possibly more irritability, pessimism and less guilt. These are elements which can orient towards severe depressions which are relatively rare, ”specifies the Professor Drapier. “But there are still cases of delirious melancholy in Parkinsonian patients with extremely severe episodes. psychotic symptoms, cognitive disorders and a high suicidal risk.”

“There are also two points that are important to consider when working on the depression of the Parkinsonian subject. ” said the speaker. On the one hand. apathy – frequent in depression -, it is also in Parkinsonian subjects, with significant prevalence, up to 40 % of patients. “This is a deficit in motivation in the field of behavior. cognitions and emotions which, unlike depression, is not accompanied by moral suffering, but it is there any links? probably predictor of a greater cognitive decline”.

The other aspect relates to non -motor fluctuations. “If motor fluctuations are well known. non -motor fluctuations – what are called the thymic offs that exist in most patients – are to be taken into account at the time of evaluations,” said the psychiatrist.

As for the question of whether we are more at risk of making a bipolar disorder when one suffers. from a parkinsonian disorder? “The answer is rather yes” for the Rennes psychiatrist.

A study on 100 Parkinsonian patients – included consecutively – shows that only 42 % of them have no mood disorder. a very low proportion, while the rest of the patients have type 1 or type 2 or type 2 or hypomania induced disorders ^[7].

What about the mania?

If Parkinson’s disease makes the bed of depression, the reverse is also true. “There is little there any links? data. cohorts, but it is established that late depressions are associated with a greater risk of developing Parkinsonian disorders ^[8]– Psychiatrists, moreover, know it very well. Mania episodes can also be observed in Parkinsonian patients, with particular characteristics in this context ^[9,10,11]. “These are very often induced forms, which goes completely in the classification of the type 3B. It is true that we are used to seeing many under antidepressants, corticosteroids, etc. They are also frequent under dopaminergic agonists, but also secondary to deep cerebral stimulation, ”describes the Profit Drapier.

And so, when you have a bipolar disorder, are we more at risk of developing a parkinsonian disorder? The answer is also yes.

“In terms of epidemiology. there are risk reports of the association between bipolar disorder and MP which are quite significant on monitoring over several years, outside of consideration relating to treatments ^[12,13]. Even if in bipolar patients there any links? who have developed abnormal movements. many of them have received antipsychotics, which probably worsens the situation. But anyway, the risk of presenting extrapyramidal diseases does not summarize the taking of anti-psychotics ”considers the speaker.

A study that compared 56. 000 bipolar patients against 225,000 non -bipolar has shown a very large number of subjects that have developed a parkinsonian disease in the group of bipolar subjects ^[12].

Do we have an explanation on the physiological level?

The pathophysiological mechanisms explaining the association of Parkinson and TB disease are unknown. The pathophysiology between MP and TB could be explained by the hypothesis of dopaminergic dysregulation. Studies that have also reached the important role in degeneration of serotonin, which would generate apathy, anxiety and depression. “And then there are other tracks that are being researching more that are on other neurotransmitters. If the dopaminergic track seems the most obvious, it there any links? is likely that things are more complex. We cannot exclude the inflammatory track as in all these problems of mood disorder. and also the genetic track ”explains the speaker.

Therapeutic management of patients ^{[14. 15,16,17]}

For depression, we will recall the interest, for the moment, of antidepressants, inhibitors of the reuptake of serotonin, tricyclic – “to be handled with precaution for patients whose risk of bipolar disorder. However, this does not mean that they should not be prescribed, but to monitor, ”specifies the psychiatrist.

Professor Drapier offers an interesting solution which consists in modulating on the dosage of dopaminergic agonists to try to. mediate mood in Parkinsonian patients. “Electroconvulsive therapy (ECT) works completely well, and has the interest of improving not only motor symptoms and psychic symptoms. You have to think about it as soon as the severity of pathology can justify it ”.

Thymo-regulation is more there any links? complicated to use in patients with severe bipolar disorders and a completely classic MP. “The reference treatment is still lithium as always in severe bipolar disorder with the idea of ​​maintaining relatively low. rates of lithiemia so as not to impact motor management”. Other molecules such as anti-psychotics can also have their role.

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