Anxiety-Induced Tremors in a 13½-Year-Old Female With Idiopathic Parkinson’s Disease

SIR: Cases of idiopathic juvenile Parkinson’s disease are rarely reported in pediatric literature. Cases of the disease starting before the age of 40 are reported at a rate of either 0 - 0.8 or 4.7 per 100,000, depending on which studies are used.¹

Parkinson’s disease (PD) is a sporadic neurodegenerative disorder, with characteristic motor defects caused by a deficiency of dopaminergic neurons in the brain’s nigrostriatal pathway.² Currently, it is uncertain whether the presence of Lewy bodies, uncovered in dopaminergic neurons of postmortem cerebral tissue, is a cause or a result of the disease. Recent studies on the Parkin gene suggest that the disease may stem from a rare autosomal-recessive juvenile form in certain familial deoxyribonucleic acid (DNA) structures. Regardless of the origin, the condition involves a loss of dopamine input to the neostriatum, causing a rigidity of muscles and bradykinesia (slowed movement).³ As a result, dopaminergic compounds have been used to treat symptoms in both adult and juvenile cases, with varied success.

As with any neurological disease, particularly those that affect younger patients, there are a host of psychological effects, which may include depression and anxiety, along with a sense of hopelessness that may accompany symptoms of autonomic activity. Of the symptoms described, those that involve a manifestation similar to symptoms of the disease can be confusing and inhibiting, both to the patient and to the patient’s family. Symptoms that overlap in conditions of anxiety and neurological illness have been addressed in the literature,^4,5,6 as they present a particular challenge to the patient and treatment provider.

There are specific techniques that have been used to aid patients in differentiating between symptoms of their illness and autonomic activity produced by anxiety. Such techniques include cognitive mediational strategies, relaxation training, and pharmacotherapy.⁴

Cognitive-behavioral techniques combined with pharmacotherapy has become the treatment of choice for anxiety disorders,⁷ particularly those involving physical and neurological illnesses.^7,8 The difficulty with particular disorders such as PD is that the symptoms of anxiety overlap the symptoms of PD that occur with either preexisting or poststatus conditions.

The following case example of idiopathic juvenile PD highlights the described dilemma. Subsequent to her initial diagnosis and treatment with anti-Parkinson’s compounds, the patient developed anxiety-induced tremors, in both social and school situations, that failed to improve with anti- Parkinson’s compounds alone. The treating neurologist initially attempted a trial of a low dose benzodiazepine (Clonazepam, 0.5 mg, 1 tab., 6 hrs. p.r.n.) as well as a selective serotonin reuptake inhibitor (SSRI) (Sertraline, 50 mg, 1 tab. q. a.m.). However, even at low doses these compounds, combined with the anti-Parkinson agents, caused drowsiness. Consequently, the neurologist referred the patient for cognitive-behavioral treatment in order to help alleviate the anxiety-induced tremors. Cognitive-behavioral techniques combined with pharmacotherapy (anti-Parkinson compounds) were employed to address both the patient’s anxiety and the tremors that were due to the PD.

Case Report

A 13½-year-old, Caucasian female was referred for treatment by her pediatric neurologist because of what was suspected to be anxiety-induced tremors overlapping the tremors caused by PD. She was seen by a pediatrician after her parents noticed that her right hand was trembling persistently. Along with the tremor, she developed right-hand stiffness with gradual onset. She reported marked cramping of her hand. There were no symptoms present involving the left side of her body. There also existed cogwheel-type rigidity affecting her right arm with bradykinesia. Additionally, dopa-responsive dystonia, as well as exposure to toxins, such as neuroleptic medications, were ruled out. The patient’s parents thought that her symptoms were due to stress and contacted her pediatrician, who referred her to a pediatric neurologist. A complete neurological examination was conducted along with a computerized axial tomography (CAT) scan, magnetic resonance imaging (MRI), position emission tomography (PET) scan, blood profiling, and a spinal tap. The PET scan revealed bilateral asymmetric redirections in striatal [18F]-6-fluoro-L-Dopa (FDOPA) uptake consistent with idiopathic PD. The condition of essential tremors was ruled out and further testing ruled out conditions including myasthenia, Lyme’s disease, Wilson’s disease, and others. The patient’s symptoms progressed over a 3-4 month period to include upper body weakness, rigidity, masked face, low tone speech, and brady kenesia. At time of her initial diagnosis of PD, her height was documented at 4′2″ with a weight of 79 lbs.

There was no reported history of Parkinson disease in the patient’s family-of-origin, although her paternal grandmother is full-blooded Japanese, and the literature suggests a familial occurrence of PD in approximately 40% to 50% of Japanese juvenile PD cases.^1,2

The patient’s parents reported that she was born 4 months premature. She had febril seizures from 14 months to 5 years of age, which were treated with phenobarbital. As a result, the seizures abated. Phenobarbital was eventually discontinued with no reoccurrences.

At the time of the initial psychiatric consultation, She was taking Mirapex, .125 mg, 1 tab, q.d., ( a dopamine agonist), which had some initial effect in reducing her Parkinson’s symptoms. She had become anxious, not only about her condition, but also because her symptoms were increasingly evident to her peers, especially to her classmates. She reported that her classmates stared at her, which made her feel like a “freak.” In addition, she was slow to complete her assignments and was falling behind in her academics. Perhaps, what was most distressing was that she was an avid writer, known in her class for interesting stories, but because her coordination had decreased, she was unable to hold a pen steadily enough to write. Consequently, her anxiety escalated even more. Her neurologist attempted a trial of low dose benzodiazepine and an SSRI, but the sedative effects of both made her too drowsy and the compounds were discontinued.

Upon the initial clinical interview, the patient was administered the Anxiety Disorders Interview Schedule-IV (ADIS-IV)¹¹ and the Beck Depression and Anxiety Inventories.^12,13 She was diagnosed with anxiety disorder due to idiopathic PD along with a mild depression.

She was also administered the Beck Anxiety, Depression, and Hopelessness inventories¹⁴ throughout the course of treatment and during follow-up in order to monitor her progress. Treatment for the patient involved teaching a course of progressive muscle relaxation (PMR) and breathing techniques in order to reduce her anxiety. She also learned methods of cognitive mediation for negative thoughts that tended to escalate her anxiety, such as “I am a freak,” or “I’ll never get better,” or “I am going to live like an old person all of my life.” She was instructed to practice the various exercises twice daily and to do them anytime she began to experience anxiety or autonomic activity. Her greatest challenge seemed to be dealing with thoughts that her anxiety symptoms were actually symptoms due to the PD. Therefore, a mantra was collaboratively developed for her: “The medication is working on my Parkinson’s - these symptoms are due to anxiety. I just need to calm down and relax myself and reduce my anxiety.” She would repeat these sentences to herself and then continue to focus on controlling her breathing and tensing and relaxing the muscle groups in her body. Additional emphasis was also placed on helping she attempt to differentiate between tremors due to her anxiety and those attributable to the PD. She was told to use the PMR to mediate the symptoms of her anxiety and to accept that fact that any residual motor tremor or stiffness may be due to the PD. She eventually came to realize that the majority of her tremor was anxiety related since that Maripex was effective in reducing her PD tremors. Treatment occurred over the course of three months with a six-month follow-up period.

In addition to cognitive-behavior therapy and the use of anti-Parkinsonian compounds, a sundry of other interventions were used to reinforce the patient’s treatment. The therapist met with the patient’s immediate family in order to guide them in supporting her emotionally. They were encouraged to be patient with her and to remind her to utilize her coping skills.

She was referred for speech therapy to address her mild to moderate dysarthia, which was characterized by weak volume and limited oral opening during speech. She struggled with an oral phase dysphagia induced by the PD that included mask-like facial features, rigidity, and rapid rate of speech.

She also attended physical therapy two to three times per week at a hand center for conservation and preservation of hand motion. She participated in a low-impact program to increase her gross motor strength and the hand strength of both arms.

The patient's BAI, BDI-II, and BHS scores demonstrated a significant reduction during the course of the 10-week treatment phase and maintained stability during the 6-month follow-up period.

Comment

This is a rather distressing, but instructive case of a young woman, who developed overlapping symptoms of anxiety tremor and PD, a neurological illness rare for her age group. Emotional reactions, displaying a variety of anxiety symptoms or depression, would certainly be expected in such cases.

An interesting aspect of this case is the fact that nonpharmacological techniques were used in lieu of anxiolytic compounds due to their untoward effects. This decision was made because the sedative effects of the benzodiazepine and SSRI’s potentiated the existing central nervous system (CNS) effects of the anti-Parkinson’s medication. The patient responded well to PMR and to cognitive coping skills, such as thought restructuring. A 6-month follow-up showed little to no anxiety symptoms and her Parkinson’s symptoms were controlled nicely with the dopamine agonist.

Obviously, there are always caveats in interpreting the data obtained from a single, non-placebo-controlled case. For one, regression to the mean may be a partial explanation for why symptoms of anxiety may have abated after the introduction of cognitive behavioral therapy (CBT) techniques. Thus, the generalizability of the intervention would have to be considered somewhat tenuous unless the case were to be repeated using more subjects and an adequate control, which, given the rarity of the situation, was not feasible. It should be noted too that these results may more likely be repeated with a population of older adults, although in cases of geriatric patients, other confounding variables, such as an additional medication regime for other ailments, may have to be taken into account.

Anxiety presents a challenge in cases of neurological illness, particularly when symptoms interact and mimic each other. One way of disentangling symptomatology is using PMR and cognitive restructuring techniques, such as those described above, in order to aid in abating the symptoms of anxiety.^4,5 The advantage of this approach is that it provides the patient with coping mechanisms and avoids the untoward side effects or negative synergistic effects that can accompany other compounds when used in treatment.

ACKNOWLEDGMENTS

The author thanks Lawrence Levitt, M.D. for providing helpful comments and Eric Frey for assistance with the literature review.