Managing antipsychotic-induced acute and tardive dystonia

Reversible Dysphagia Associated With Risperidone Presenting With a Choking Episode

Dysphagia has been associated with antipsychotic drug use. This case report describes the management of dysphagia in a psychiatric patient who presented to the emergency department from a psychiatric facility after choking on a hot dog. The patient was on risperidone 4 mg, initiated a month prior to treat acute psychosis. Foreign body removal from the distal trachea was performed by bronchoscopy, followed by a swallow evaluation by the speech and swallow team. The patient exhibited severe oropharyngeal dysphagia, leading to aspiration pneumonia and subsequent enteral feeding through a nasojejunal tube. Changes in medication from risperidone to aripiprazole, along with a short course of benztropine and dietary modifications, were implemented, with gradual improvement in swallowing function observed during the hospital stay. The patient's complex medical and psychiatric history contributed to a prolonged hospital stay.

Movement disorders of the mouth: a review of the common phenomenologies

Movement disorders of the mouth encompass a spectrum of hyperactive movements involving the muscles of the orofacial complex. They are rare conditions and are described in the literature primarily in case reports originating from neurologists, psychiatrists, and the dental community. The focus of this review is to provide a phenomenological description of different oral motor disorders including oromandibular dystonia, orofacial dyskinesia and orolingual tremor, and to offer management strategies for optimal treatment based on the current literature. A literature search of full text studies using PubMed/Medline and Cochrane library combined with a manual search of the reference lists was conducted until June 2021. Results from this search included meta-analyses, systematic reviews, reviews, clinical studies, case series, and case reports published by neurologists, psychiatrists, dentists and oral and maxillofacial surgeons. Data garnered from these sources were used to provide an overview of most commonly encountered movement disorders of the mouth, aiding physicians in recognizing these rare conditions and in initiating appropriate therapy.

Phenothiazine antipsychotics exhibit dual properties in pseudo-allergic reactions: Activating MRGPRX2 and inhibiting the H1 receptor

Phenothiazines are a class of antipsychotics that share the same tricyclic structure and are widely used in clinical settings. Adverse reactions from these drugs, however, have been regularly reported, with allergic skin reactions noted in some cases. Nevertheless, the mechanisms underlying anaphylaxis by these drugs have not been described. In the present study, we found that phenothiazine antipsychotics increased calcium mobilization and activated mast cells to release β-hexosaminidase, histamine, and tumor necrosis factor-α via Mas-related G-protein-coupled receptor member X2 (MRGPRX2) in vitro. In addition, they induced histamine release in serum via Mrgprb2 in C57BL/6 mice without Evans blue extravasation or paw swell. Further experiments indicated these drugs had good interaction with the histamine H₁ receptor (H1R) and show an anti-calcium mobilization effect on H₁R-HEK293 cells, which confirmed a potential antagonist effect of these drugs on the H₁R. The molecular docking and activity experiments indicated that the N-methyl substitution on the side chain of these drugs played a significant role in activating MRGPRX2, while the phenothiazine tricyclic ring was associated with the inhibiting effect on the H₁R. Therefore, due to their dual properties of increasing histamine levels without obvious allergic symptoms, clinicians should be highly vigilant for damage from histamine accumulation and long-term inflammatory reactions during the clinical use of phenothiazine antipsychotics.

Medicinal-Induced Behavior Disorders

Commonly used medications can have neuropsychiatric and behavioral effects that may be idiosyncratic or metabolic in nature, or a function of interactions with other drugs, toxicity, or withdrawal. This article explores an approach to the patient with central nervous system toxicity, depending on presentation of sedation versus agitation and accompanying physical signs and symptoms. The effects of antihypertensives, opioids, antibiotics, antiepileptic agents, steroids, Parkinson's disease medications, antipsychotics, medications for human immunodeficiency virus infection, cancer chemotherapeutics, and immunotherapies are discussed. A look at the prevalence of adverse reactions to medications and the errors underlying such occurrences is included.

Acute Dystonic Reaction and the Neuroleptic Malignant Syndrome

Up to 90% of patients on chronic antipsychotic therapy will experience adverse neurologic side effects, with many of these effects attributable to the dopamine-blocking properties of these drugs. Even the newer, “atypical” antipsychotics are increasingly associated with neurologic complications. In the acute care setting, these medications have broad application beyond the management of psychiatric illness. Given the extent of their use, clinicians should be familiar with the spectrum of neurological syndromes that can develop. Some are common, such as akathisia, acute dystonic reaction, tardive dyskinesia, and drug-induced parkinsonism. Others, such as the life-threatening neuroleptic malignant syndrome, are rare yet must be recognized early to affect survival and improve outcome. This discussion highlights 2 idiosyncratic syndromes, acute dystonic reaction and neuroleptic malignant syndrome. The differential diagnosis for both syndromes and their management is discussed.

Second-generation antipsychotics and extrapyramidal adverse effects

Antipsychotic-induced extrapyramidal adverse effects are well recognized in the context of first-generation antipsychotic drugs. However, the introduction of second-generation antipsychotics, with atypical mechanism of action, especially lower dopamine receptors affinity, was met with great expectations among clinicians regarding their potentially lower propensity to cause extrapyramidal syndrome. This review gives a brief summary of the recent literature relevant to second-generation antipsychotics and extrapyramidal syndrome. Numerous studies have examined the incidence and severity of extrapyramidal syndrome with first- and second-generation antipsychotics. The majority of these studies clearly indicate that extrapyramidal syndrome does occur with second-generation agents, though in lower rates in comparison with first generation. Risk factors are the choice of a particular second-generation agent (with clozapine carrying the lowest risk and risperidone the highest), high doses, history of previous extrapyramidal symptoms, and comorbidity. Also, in comparative studies, the choice of a first-generation comparator significantly influences the results. Extrapyramidal syndrome remains clinically important even in the era of second-generation antipsychotics. The incidence and severity of extrapyramidal syndrome differ amongst these antipsychotics, but the fact is that these drugs have not lived up to the expectation regarding their tolerability.

Glucose hypermetabolism in the thalamus of patients with drug-induced blepharospasm

We examined the difference in cerebral function alterations between drug-induced blepharospasm patients and essential blepharospasm (EB) patients by using positron emission tomography with (18)F-fluorodeoxyglucose. Cerebral glucose metabolism was examined in 21 patients with drug-induced blepharospasm (5 men and 16 women; mean age, 53.1 [range, 29-78] years), 21 essential EB patients (5 men and 16 women; mean age, 53.0 [range, 33-72] years) and 24 healthy subjects (6 men and 18 women; mean age, 57.9 [range, 22-78] years) with long-term history of benzodiazepines use (drug healthy subjects). Drug-induced blepharospasm patients developed symptoms while taking benzodiazepines or thienodiazepines. Sixty-three normal volunteers (15 men and 48 women; mean age, 53.6 [range, 20-70] years) were examined as controls. Differences between the patient groups and control group were examined by statistical parametric mapping. Additionally, we defined regions of interests on both sides of the thalamus, caudate nucleus, anterior putamen, posterior putamen and primary somatosensory area. The differences between groups were tested using two-sample t-tests with Bonferroni correction for multiple comparisons. Cerebral glucose hypermetabolism on both side of the thalamus was detected in drug-induced blepharospasm, EB patients and drug healthy subjects by statistical parametric mapping. In the analysis of regions of interest, glucose metabolism in both sides of the thalamus in the drug-induced blepharospasm group was significantly lower than that in the EB group. Moreover, we observed glucose hypermetabolism in the anterior and posterior putamen bilaterally in EB group but not in drug-induced blepharospasm group and drug healthy subjects. Long-term regimens of benzodiazepines or thienodiazepines may cause down-regulation of benzodiazepine receptors in the brain. We suggest that the functional brain alteration in drug-induced blepharospasm patients is similar to that in EB patients, and that alteration of the GABAergic system might be related to the pathology of both blepharospasm types.

Drug-Induced Movement Disorders in Older Adults: An Overview for Clinical Practitioners

OBJECTIVE

To provide an overview of some of the most common drug-induced movement disorders (DIMD) seen in the elderly by the primary care clinician. The epidemiology, clinical presentation, differential diagnosis, treatment, risk factors, and preventive measures are presented for each DIMD.

DATA SOURCES

Medical literature and research article search utilizing PubMed (National Library of Medicine), Psych INFO (American Psychological Association), CINAHL Database (CINAHL Information Systems), the Library of Congress Catalogue, and the Internet.

STUDY SELECTION

Reviews and articles from 1954 to 2005 concerning various movement disorders associated with medication in older adults. DATA EXTRACTIONS: Data on movement disorders associated with medications ranging from possible or controversial to well-established.

DATA SYNTHESIS

With the aging of populations in the United States and other countries, the use of medications with potential risk of precipitating movement disorders is increasing. The majority of these iatrogenic problems will be first seen in the geriatric patient in various clinical settings, typically in a primary care setting. To a large extent they will be observed in patients with mild cognitive impairment or dementia having impaired recall and reduced capacity to participate in the diagnostic interview. The challenge to clinicians is complicated by the sizable number of medications that may be involved.

Practical guidelines for the use of new generation antipsychotic drugs (except clozapine) in adult individuals with intellectual disabilities

New generation antipsychotic (NGA) drugs introduced to the US market after clozapine (aripiprazole, olanzapine, paliperidone, quetiapine, risperidone, and ziprasidone) are frequently used in individuals with intellectual disabilities (ID). However, there is very limited research to fully establish evidence-based or personalized medicine approaches for their use in this population. These guidelines take a pragmatic approach to establishing frameworks for their use by utilizing the prescribing information and reviewing the available literature on other relevant neuropsychiatric disorders. In the absence of expert consensus guidance and well-controlled comparison trials, we present a set of guidelines to inform initiation, dosing and monitoring of use in adults. Further, in these guidelines we provide practical information on drug-drug interactions and adverse drug reactions, and a brief review of discontinuation syndromes, potential for abuse, use during pregnancy and cost considerations. We also provide drug utilization review forms for each NGA to facilitate implementation of these guidelines, these guidelines provide a practical and necessary resource for practitioners treating psychiatric disorders and challenging behaviors in adult individuals with ID.

Orofacial movement disorders

This article reviews three poorly recognized yet relatively common presentations of hyperactive orofacial movement disorders: oromandibular dystonia, orofacial dyskinesia, and drug-induced extrapyramidal syndrome reactions. Orofacial movement disorders are often misdiagnosed as temporomandibular disorders, hence understanding these conditions is pertinent for the practitioner treating orofacial pain. Aspects of epidemiology, etiology, pathophysiology, clinical presentation, and diagnosis are discussed along with treatment considerations for these orofacial movement disorders.

Methamphetamine psychosis in which tardive dystonia was successfully treated with clonazepam

Reported herein is a case of methamphetamine psychosis in which tardive dystonia was treated successfully with clonazepam. The patient was a 69-year-old man who had taken methamphetamine habitually for approximately 40 years. Auditory hallucinations had developed 25 years previously, for which haloperidol had been prescribed. Tardive dystonia had developed in December 2005. Haloperidol was withdrawn and risperidone or olanzapine alone had been administered, but neither had improved the dystonic posture. However, when clonazepam was added, a gradual improvement in the dystonic posture became evident. Tardive dystonia is currently treated on a trial-and-error basis. Accumulation of further cases similar to the present one is very important for establishing an effective treatment.

Four oral motor disorders: bruxism, dystonia, dyskinesia and drug-induced dystonic extrapyramidal reactions

This article reviews four of the involuntary hyperkinetic motor disorders that affect the orofacial region: bruxism, orofacial dystonia, oromandibular dyskinesia, and medication-induced extrapyramidal syndrome-dystonic reactions. It discusses and contrasts the clinical features and management strategies for spontaneous, primary, and drug-induced motor disorders in the orofacial region. The article provides a list of medications that have been reported to cause drug-related extrapyramidal motor activity, and discusses briefly the genetic and traumatic events that are associated with spontaneous dystonia. Finally, it presents an approach for management of the orofacial motor disorders. The contraindications, side effects, and usual approach for medications and injections are covered. An overview of the indications, contraindications, and complications of using botulinum toxin as a therapeutic modality is discussed briefly.

Side effects of atypical antipsychotics: extrapyramidal symptoms and the metabolic syndrome

In this article we examine the two major classes of side effects with atypical antipsychotics: extrapyramidal symptoms (EPS) and the metabolic syndrome (the triad of diabetes, dyslipidemia, and hypertension, with associated obesity). We conclude that atypical antipsychotics continue to have notable risks of EPS, particularly akathisia, and that these agents also appear to increase the risk of the metabolic syndrome, though this effect seems most marked with clozapine and olanzapine. Novel conclusions based on this review are as follows: we provide a classification scheme based on low versus high D2 binding affinity (which is, to our knowledge, a new means of classifying atypical antipsychotics); we emphasize that the akathisia risk is likely equal among agents and that tardive dyskinesia is an early, and not late, risk in treatment (a common misconception); we make the methodological point that in randomized clinical trials, there is a high risk of false-negatives regarding side effects; we raise the issue of confounding bias in epidemiological studies of metabolic syndrome; and we stress the need to compare side effects in the same studies and not different studies. Future prospective observational cohort studies must target side effects and be designed to collect and analyze data on confounding factors.

Reducing the dose of antipsychotic agents ameliorates visual hypersensitivity attack: an ideal treatment option in terms of the adverse effect

There are sporadic reports of antipsychotic-induced visual hypersensitivity attack (VHA). VHA is characterized by hypersensitivity of perception mainly in the visual modality and sometimes accompanied by an oculogyric crisis. However, some researchers regard VHA as a schizophrenia symptom. To determine whether VHA is an adverse effect of antipsychotic agents, we examined the effect of dose reduction on VHA. This was an open-label 36-week study. We randomized 34 patients with VHA to a reduced-dose group and a fixed-dose group. Primary outcome measures were the frequency and duration of VHA, assessed with patients' self-reports, and the Clinical Global Impressions (CGI). Assessment also included the Drug-induced Extrapyramidal Symptoms Scale for extrapyramidal symptoms, the Positive and Negative Syndrome Scale (PANSS) for schizophrenia, and the CGI for other diagnoses. Data were collected from August 2000 to April 2005 at 4 psychiatric hospitals in Tokyo.VHA diminished in 16 patients (94.1%) in the reduced-dose group in the CGI score, the frequency (number of episodes per week), and the duration of the episodes (from 4.06 to 1.77, P < 0.001; from 2.59 to 0.82, P = 0.001; and from 1.92 to 0.66 hours, P = 0.007, respectively), but there were no changes in the fixed-dose group. There were no changes in the underlying illness as measured by the PANSS in both groups. Reducing the dose of antipsychotic agents ameliorates VHA and represents the ideal treatment option for patients with VHA.

High vulnerability to acute dystonic reactions: a case of antipsychotic exposure and uncontrolled seizure activity

Antipsychotic-induced extrapyramidal side effects have a negative impact on treatment for mental illness. Acute dystonic reactions are uncomfortable and frightening to the patient, and often lead to early discontinuation of drug therapy and worsened long-term outcome. The lower propensity of the atypical antipsychotic agents to cause extrapyramidal symptoms (EPS) has been associated with multiple benefits, including improved adherence. The authors describe a 57-year-old male patient who was in the treatment refractory unit. This patient exhibited extreme sensitivity to antipsychotic agents, experiencing acute dystonic reactions with quetiapine and olanzapine, in addition to older typical antipsychotic agents. The patient has not experienced acute EPS since therapy with aripiprazole was initiated. Further complicating this patient's course is his unusual sensitivity to experiencing dystonic reactions. We have observed acute dystonias in the absence of antipsychotic treatment and in the context of seizure activity (or paroxysmal dyskinetic activity). The true etiology of the latter dystonic activity has not been completely determined due to the patient's unwillingness to cooperate with invasive testing. None of the gene variations tested (CYP2D6 phenotype, two dopamine D2 receptor variants and one D3 receptor variant) appeared to explain the patient's vulnerability to acute dystonic reactions.

Tetrabenazine Treatment in Movement Disorders

Tetrabenazine (TBZ) is a catecholamine depletor used for the treatment of a variety of movement disorders. The purpose of this study was to assess the efficacy of TBZ in a retrospective chart review in 3 tertiary care movement disorders centers over long-term treatment. Of 150 patients to whom TBZ was prescribed, 118 were followed up and assessed using the Clinical Global Impression of Change (CGIC), (-3 to +3), a composite grade from a patient and caregiver scale over variable periods. The patients had a variety of hyperkinetic movement disorders including dystonia (generalized and focal: axial, Meige syndrome, torticollis, blepharospasm, bruxism), Huntington disease (HD) or other choreas, tardive dyskinesia (TD) or akathisia, and Tourette syndrome. Mean patient age was 48.8 +/- 18.7 years; 48 were men (40.7%) with a mean disease duration of 93 months. The mean follow-up time was 22 months and the mean TBZ dose was 76.2 +/- 22.5 mg/d (median 75 mg, range 25-175 mg/d). The mean CGIC score was +1 (mild improvement). The group of patients who scored +3 on the CGIC (very good improvement) represented 18.6% (n = 22) of all patients. They had HD or other types of chorea 7.6% (n = 9), facial dystonia/dyskinesia (n = 7, 5.9%), 1 with TD, 2 with trunk dystonia, 2 with Tourette syndrome, and 1 with tardive akathisia. This group had the longest treatment duration and received a mean TBZ dose of 70.5 mg/d (median 75 mg/d) for a mean of 25.4 +/- 21.3 months. The report concludes that TBZ is a moderately effective treatment of a large variety of hyperkinetic movement disorders, with excellent effects in a subgroup with chorea and facial dystonia/dyskinesias.

Efficacy of pharmacological treatment of dystonia: evidence-based review including meta-analysis of the effect of botulinum toxin and other cure options

The treatment of both generalized and focal dystonia is symptomatic. There is no evidence-based information about the efficacy of the different methods of the pharmacological therapeutic options currently being applied in dystonia. The specific questions addressed by this study were which treatments for dystonia have proven efficacy and which of them have unproven results. Following evidence-based principles, a literature review based on MEDLINE and the Cochrane Library, augmented by manual search of the most important journals was performed to identify the relevant publications issued between 1973 and 2003. All articles appearing in the professional English literature, including case reports, were considered. In the presence of comparable studies the meta-analysis was performed to obtain pooled information and make a reasonable inference. Based on this review, we conclude: (i) botulinum toxin has obvious benefit (level A, class I-II evidence) for the treatment of cervical dystonia and blepharospasm; (ii) trihexyphenidyl in high dosages is effective for the treatment of segmental and generalized dystonia in young patients (level A, class I-II evidence); (iii) all other methods of pharmacological intervention for generalized or focal dystonia, including botulinum toxin injections, have not been confirmed as being effective according to accepted evidence-based criteria (level U, class IV studies).

Mouvements anormaux d’origine médicamenteuse : les syndromes tardifs

Persistent drug-induced movement disorders (tardive syndromes) remain an important clinical problem and consist of a variety of involuntary movements appearing in a patient exposed to a dopamine-blocking agent. The current state of knowledge on this topic is summarised in this article. Clinical aspects (tardive dyskinesia, tardive dystonia and other forms), prevalence, risk factors, prevention and management are discussed.

Recurrent episodes of perceptual alteration in patients treated with antipsychotic agents

Antipsychotics have been sporadically reported to induce the brief recurrent episodes characterized by hypersensitivity of the visual perception, which is known as paroxysmal perceptual alteration (PPA) mainly in Japan. PPA is characterized by hypersensitivity of perception mainly in visual modalities, which could occur in patients treated with antipsychotics. PPA is occasionally known to be accompanied by an oculogyric crisis (OGC). In this study, we examine the prevalence and the characteristics of patients with PPA. Three hundred thirty-eight patients who were treated with antipsychotics and diagnosed with schizophrenia, mood disorders, or neurotic disorders (International Classification of Disease, or ICD-10) were interviewed. We compared the characteristics between subjects with and without PPA. The mean overall prevalence of PPA was 3.25%, which was higher among patients treated with high-potency antipsychotics (3.91%) than in subjects treated with mid-potency or low-potency drugs (1.16%). PPA occurred simultaneously with OGC at the rate of 36.4%. We also found much similarity between PPA and OGC in terms of phenomenology. We suggest that PPA could manifest itself as an undesirable effect of antipsychotics, especially those of high potency. PPA and OGC may a share common underlying mechanism.

Antipsychotic drug-induced movement disorders

Very early in the process of diagnosing abnormal involuntary movement (AIM) disorders, one can be rewarded by keeping a high index of suspicion for possible drug-induced causes, not only through a complete list of current medications, but also identification of the drugs the patient used to take and other possible offending medications that might be available from family members and other sources. Among drug-induced movement disorders, antipsychotic drugs and other dopamine receptor blocking agents occupy a central place. Their various acute and tardive motor complications provide the template of this short review. Movement disorders caused by antidepressants, lithium, antiemetics, antiparkinsonian agents, anticonvulsants, calcium channel blockers, sympathomimetics and others are only briefly covered in table form.

Dyskinesia: L-dopa-induced and tardive dyskinesia

Neuroleptic induced tardive dyskinesia and L-dopa-induced dyskinesia are the two most common types of drug-induced abnormal involuntary movements. These two drug-induced dyskinesias are clearly different with respect to the offending drugs and the underlying disease, but they both share a number of intriguing similarities in terms of clinical phenomenology, epidemiology, risk factors, pathophysiological mechanisms and therapeutic responses. In both instances, it is believed that some dysregulation occurring at the level of the striatal dopaminergic receptors, and related non-dopaminergic neurotransmitters systems are playing a crucial role in the development and persistence of the mechanisms causing dyskinesia. These long-lasting functional changes, known as the "priming" phenomenon, are responsible for an impaired balance within the relays of the cortico-subcortical motor loops that release an inadequate output from the basal ganglia leading to an abnormal motor behavior. From a therapeutic perspective, there are also many similarities in the strategies proposed to manage these two dyskinesias. In both cases, unprimed patients not previously exposed to the offending drugs, are offered alternative medications to reduce, at least partly, the risk of occurrence of future dyskinesia: "atypical" neuroleptics in the place of "typical" neuroleptics, and dopamine agonists in the place of L-dopa. In both cases, once dyskinesias are present, in already "primed" patients, both types of dyskinesia appear to be poorly and only partly reversible. Based on limited clinical evidence, it is a common proposal to switch the dyskinetic subject from "typical" to "atypical" neuroleptics for tardive dyskinesia, or to switch from (or more pragmatically to substitute as much as possible) L-dopa to a dopamine agonist for L-dopa-induced dyskinesia. In both cases, efficacious symptomatic antidyskinetic interventions, to reduce the severity of a ready present dyskinesia, are rare. There are some uncontrolled data suggesting that dopamine depleting agents, like tetrabenazine, are possibly useful for tardive dyskinesia; however, there is more clinical evidence to support the efficacy of amantadine and functional surgery in parkinsonian patients with L-dopa-induced dyskinesia.

Antipsychotic-Induced movement disorders in the elderly: epidemiology and treatment recommendations

We reviewed the epidemiological aspects of antipsychotic-induced movement disorders as they pertain to older patients. The incidence and prevalence of drug-induced parkinsonism and tardive dyskinesia (TD) are significantly greater in the older patient than in the younger patient whereas akathisia seems to occur evenly across the age spectrum and dystonia is uncommon among older patients. The literature on risk factors associated with treatment-emergent movement disorders is highly variable. Treatment practices vary across the age range and the interaction between age and antipsychotic dosage confounds our understanding of the relative importance of treatment-related risk factors. However, there is general agreement that pre-existing extrapyramidal signs (EPS) increase the vulnerability of the patient to developing significant drug-induced movement disorders. Elderly patients with dementia are at greater risk than patients without dementia for persistent drug-induced EPS. Management of drug-induced movement disorders in the older patient requires careful consideration of the contraindications imposed by such agents as anticholinergics and beta-blockers. At present, well-controlled double-blind studies of second-generation antipsychotics such as clozapine, risperidone. olanzapine or quetiapine for reducing the risk of treatment-emergent movement disorders in the elderly have not been published. However, open-label studies of atypical antipsychotics demonstrate a markedly lower incidence of both EPS and TD compared with conventional antipsychotic treatment in the elderly. There is emerging literature in support of atypical antipsychotics for the treatment of existing drug-induced movement disorders. More controversial is the use of adjunctive antioxidants in newly treated patients who are vulnerable to drug-induced movement disorders. While the evidence is mixed in support of antioxidants for the treatment of TD, the possibility remains that prophylactic use of antioxidants may help reduce the incidence of TD. The development of a drug-induced movement disorder often reduces the quality of life in an elderly patient. Effective pharmacological management requires cooperation from the patient and family, which can be fostered early in the patient's care through proper informed consent. The risks and benefits of antipsychotic treatment in the elderly patient need to be communicated to the patient and family. At the present time, there is no consistently effective treatment for patients with TD once it develops. Therefore, attention should focus on its prevention and close monitoring.