Cristina Simonet Hernández (Alaró, 1987) graduated in medicine from the Autonomous University of Barcelona. He chose the General Hospital of Segovia, with frequent incursions into hospitals in Madrid, for his residency in the specialty of Neurology. He also trained at the Hospital Clínic de Barcelona for two years to deepen his knowledge of Parkinson’s disease and collaborated with the actor Michael J. Fox’s foundation, dedicated to the study of this degenerative pathology.
The subspecialty stage in movement disorders took her to Queen Mary University of London, where she met Dr. Alastair Noyce, supervisor of her doctoral thesis, which she will read in September. The journal JAMA Neurology has published an article of which she is the first author on certain symptoms which make it possible to predict up to ten years in advance that certain people will develop Parkinson’s disease.
The article is part of your doctoral thesis, what are the first indicators and how did you develop the research?
We take electronically recorded medical records from the East London area. We studied years in advance the one million people without Parkinson’s and the 1,000 who had developed the disease. We analyzed which previous pathologies were more frequent in patients who became ill compared to those who did not.
And the previously detected symptoms are related to epilepsy and hearing loss…
We studied other symptoms related to Parkinson’s disease that were already known such as tremors, balance disorders, constipation, depression… what surprised us was to detect a higher prevalence epilepsy and hearing loss in people who would develop Parkinson’s disease in the future compared to the disease-free group. Epilepsy should be taken with caution because as the drug was not registered we could not exclude that the symptoms of Parkinson’s disease were due to a side effect of anti-epileptic drugs. As for hearing loss, some studies suggest that it could be an early symptom of cognitive deterioration. The population of East London is an impoverished society with a high prevalence of pathologies such as diabetes or cardiovascular problems which could promote the development of dementia, which could explain a higher prevalence of hearing loss in this population. In both cases, it is necessary to go deeper in order to reach definitive conclusions.
More generally, what is your thesis about?
We know that Parkinson’s disease is diagnosed on the basis of motor symptoms: rigidity, tremors and slowness of movement. If a person has at least two of these symptoms, they can be detected. The idea is to know what the first motor symptoms are in order to reach an early diagnosis. For example, handwriting is known to vary widely before diagnosis. There may also be a lack of facial expression, which many family members describe as “having a straight face”. He can only arm one of the limbs when marching. These are very subtle changes, which patients do not report, but if we know about them, we have a lot of evidence of a possible beginning of the disease… In fact, images from years ago of personalities patients who have suffered from Parkinson’s disease have been studied. In the case of an English footballer named Ray Kennedy, one of my thesis mentors, Professor Andrew Lees, observed that in videos from when he was still playing, twelve years before the diagnosis, already saw that he wasn’t cocking his arm or dragging a foot anymore. My thesis studies all these subtleties before they are accentuated in order to obtain an early diagnosis.
We suffer from neurodegenerative diseases such as Alzheimer’s or Parkinson’s because we age. Can we take precautions to avoid them?
Unfortunately, it is not yet in our hands to avoid both pathologies. What we do know is that the incidence of Parkinson’s disease is increasing exponentially above what would be expected due to the aging population. There is an “additional quota” whose causes we do not know. Before preventing the disease, one must be able to diagnose it early, if successful, there are promising drugs that can act as retardants. What happens is that all of the clinical trials have been done with already diagnosed patients. It is known that once developed, more than half of the neurons are dead, so it is too late at the time of diagnosis for a drug to be effective. The challenge is to diagnose it very early in order to act in time.
How is the death of so many neurons detected?
Pathological anatomy studies have been performed, but a correlation with brain dopamine levels has also been established through functional neuroimaging studies.
160,000 cases are known in Spain, seven million worldwide, and they are growing above the aging of the population. Does ethnic origin or social status influence the development of the disease?
Studies so far have focused on white people of a certain social status. Ours was deployed in a setting of high ethnic diversity and low social status and we found no difference in the development of Parkinson’s disease. On the other hand, in studies on dementia, we have seen that the social factor could have an influence.
Do levels of training and education influence dementia?
Yes, an educational factor and we have also seen that vascular pathologies, such as hypertension or diabetes, could intervene.
Parkinson’s disease is associated with tremors as the most visible symptom, what other consequences does this have?
It affects several organs. In addition to movement, memory, the digestive tract, the sense of smell, our sleep habits… the spectrum is very broad. Some of these symptoms also affect the general population. My thesis focuses on the study of the first symptoms that affect the motor apparatus.
If detected early, can the development of Parkinson’s disease be prevented?
First we need to know the risk factors. Right off the bat, the problem is that there is no diagnostic test. A heart attack or cancer have a very reliable diagnostic test. With Parkinson’s disease, it relies on the clinical eye of the physician which is subject to a margin of error. Offering an early diagnosis to a person without being certain that they will develop it is difficult, which is why our research is dedicated to the development of prediction algorithms based on risk factors and the first symptoms.
Can it be delayed with a certain lifestyle?
Some studies suggest so. For example, with exercise and the Mediterranean diet. Research shows that exercise, in addition to being a cardiovascular protector, is beneficial for brain health. Diabetes, eating saturated fats, sugar… are risk factors. At the same time, hypertension can cause neurodegenerative diseases.
A former high political post in health and a doctor claims that diseases were once cured and now they are only palliated to prolong life.
Indeed. Once you have the diagnosis during the consultation, you start the symptomatic treatment, then we recommend a healthy lifestyle based on a Mediterranean diet and aerobic exercises. It has been seen that tai chi or tango can improve prognosis by improving the coordination circuits affected in Parkinson’s disease.
Where is the research going?
Let’s make an early diagnosis. Patients with very early symptoms are the ideal population to conduct clinical trials with drugs that are not yet on the market, but are waiting to be tested to show that they slow the disease. It’s the future.
I read another of your studies in which you warn against a reaction of hypersexuality.
It was a case that we had in the hospital in Segovia. This is a patient with Parkinson’s disease who, shortly after starting treatment with Rasagiline, developed hypersexuality which resolved shortly after stopping the drug. Impulse control disorders, such as hypersexuality and pathological gambling, are known as a side effect of the drugs we give to treat the disease that alter dopamine-driven reward circuits.
Searching in Spain is almost impossible?
Yes, it is very sad. I spent two years doing research at the Hospital Clínic de Barcelona and my salary was that of a laboratory technician. I had to do general medicine shifts in the emergency room to improve my income. The quality of research is very good in Spain, but there are no resources.
Why did you choose neurology?
My grandfather was diagnosed with cerebral meningioma while I was studying medicine. I was able to closely follow his neurological process, it touched me and aroused my interest in this specialty. On the other hand, I believe that the mind and the brain are an enigma.
What’s the most surprising thing about the brain?
I would say its adaptability. For example, if you have a stroke, after a few years lost functions can be relearned through the creation of new connections.
Work is already underway with stem cells in the recovery of tissues affected, for example, by a heart attack. Do you also work in this area with the brain?
Several studies have been conducted on the implantation of pluripotent stem cells in the affected part of the brain of Parkinsonian patients. They were intended to be able to create dopamine and thus slow down the disease process. The results are encouraging, but there is still a long way to go.
Parkinson’s, Alzheimer’s, stroke, dementia… are new brain-related diseases expected?
The field of neurology is growing exponentially. By knowing more, we expect that new pathologies will be discovered and that we will change the name of diseases that we already know. For example, we believed that epilepsy was a form of hysteria, that it was a psychiatric pathology, until the electroencephalogram arrived and we realized that we had made a mistake and that it was due to a neurological disorder. Now there are functional disorders in which people somatize, for example paralysis, and have not suffered a stroke, but are convinced that they have this problem. Today it is considered a functional pathology, not organic, but perhaps in the future, with new technologies, it will be discovered that the substrate is different.
Poetry has placed emotions in the heart. I guess a neurologist transfers them to the brain.
Or that the heart and the brain are connected.
Is the return in your plans?
I would like. We studied in public education and there is a debt to the country in which you were educated. In England, studying for a degree costs ten times more.