Methylphenidate: established and expanding roles in symptom management

Effect of methylphenidate on oculomotor function in individuals with multiple sclerosis: a pilot randomized placebo-controlled trial

Introduction

Individuals with multiple sclerosis (MS) frequently experience visual and oculomotor symptoms that may impact and confound neuropsychological assessments of information processing speed (IPS). In this study, we examined the effect of the psychostimulant methylphenidate on oculomotor function and the association between change in oculomotor speed and change in information processing speed.

Methods

We used a repeated measures crossover design in which a sample of 11 participants with MS were randomly assigned to one of two treatment arms: one that received methylphenidate for 4 weeks and another that received a placebo for 4 weeks. After a 7-day washout period, the treatments were crossed over. The King Devick test, the Symbol Digit Modalities Test, and the Paced Auditory Serial Addition Test were administered at baseline and after each of the two study arms.

Results

We found a significant improvement in oculomotor speed in the methylphenidate condition as compared to placebo. This improvement was significantly correlated with improvement on a visuomotor assessment of IPS (Symbol Digit Modalities Test), but no such association was found for an auditory-verbal assessment of IPS (Paced Auditory Serial Addition Test).

Discussion

These findings suggest that individuals with MS experience improved oculomotor speed while taking methylphenidate, which may, in turn, improve performance on assessments of IPS with visuomotor demands.

Possible Delay in Symptomatology of a Methadone Overdose in a Patient Ingesting an Energy Drink and Dextroamphetamine/Amphetamine

Introduction: Methadone is a mu-opioid agonist with a delayed time to peak concentration that requires an extended period of monitoring following an overdose. Available data suggests that the combination of psychostimulants with methadone may augment antinociception and tolerance to opioids. Case Report: A 26-year-old male (83.9 kg) presented to the ED approximately 1 hour after unintentionally ingesting 200-250 mg of liquid methadone and an energy drink, along with 20 mg of dextroamphetamine/amphetamine prior to the event. Vital signs were: blood pressure (BP), 143/91 mmHg; heart rate (HR), 74; respirations (RR), 16; oxygen saturation 95% on room air. His urine drug screen was positive for amphetamines and methadone. Patient was monitored for 4 hours with no change in status and was discharged home. Approximately 26 hours later patient was found cyanotic and apneic. Patient was given 2 mg of naloxone and awoke with normal mental status. On presentation the patient's vital signs were: BP, 114/70 mmHg; HR, 114; RR 16; oxygen saturation 94% on 3 liters nasal cannula. During his ED stay, he required 2 doses of naloxone secondary to oxygen desaturation and was admitted to the hospital. His repeat urine drug screen was positive for amphetamines and methadone. The patient was discharged the following day. Discussion: This case illustrates an unintentional methadone overdose combined with the intentional ingestion of an energy drink and dextroamphetamine/amphetamine that possibly masked the toxicity for over 24 hrs. Monitoring parameters for methadone overdoses may need re-evaluation in the setting of the co-ingestion of a stimulant.

Use of Opioids for Adults With Pain From Cancer or Cancer Treatment: ASCO Guideline

PURPOSE

To provide guidance on the use of opioids to manage pain from cancer or cancer treatment in adults.

METHODS

A systematic review of the literature identified systematic reviews and randomized controlled trials of the efficacy and safety of opioid analgesics in people with cancer, approaches to opioid initiation and titration, and the prevention and management of opioid adverse events. PubMed and the Cochrane Library were searched from January 1, 2010, to February 17, 2022. American Society of Clinical Oncology convened an Expert Panel to review the evidence and formulate recommendations.

RESULTS

The evidence base consisted of 31 systematic reviews and 16 randomized controlled trials. Opioids have primarily been evaluated in patients with moderate-to-severe cancer pain, and they effectively reduce pain in this population, with well-characterized adverse effects. Evidence was limited for several of the questions of interest, and the Expert Panel relied on consensus for these recommendations or noted that no recommendation could be made at this time.

RECOMMENDATIONS

Opioids should be offered to patients with moderate-to-severe pain related to cancer or active cancer treatment unless contraindicated. Opioids should be initiated PRN (as needed) at the lowest possible dose to achieve acceptable analgesia and patient goals, with early assessment and frequent titration. For patients with a substance use disorder, clinicians should collaborate with a palliative care, pain, and/or substance use disorder specialist to determine the optimal approach to pain management. Opioid adverse effects should be monitored, and strategies are provided for prevention and management.Additional information is available at www.asco.org/supportive-care-guidelines.

[Increasing methylphenidate abuse: Tracking and profiles during 13-years]

BACKGROUND

Methylphenidate is indicated for attention deficit hyperactivity disorder (ADHD). Several studies have evaluated its abuse in specific populations (students, drug users) and few in the general population. This work describes the extent of its abuse in a region of more than 5 million inhabitants.

METHOD

Based on regional health insurance data from 2005 to 2017, the clustering method identifies different methylphenidate use profiles according to several characteristics (number of different prescribers and pharmacies, number of dispensations, number of defined daily dose dispensed). The groups characterised by high values of these variables will be qualified as "deviant".

RESULTS

In 13 years, the number of patients with at least one dispensation in the first quarter has been multiplied by 5.8 times. The proportion of adults has increased (20% in 2017) and their number has been multiplied by 10. Five groups are identified, three of them are characterised by "deviant" behaviour. Group 5 (n=11, 0.04%) has higher values than 4 (n=112, 0.4%) and 3 (n=407, 1.6%). These patients are older and more frequently use benzodiazepines and opiate substitution drugs. Groups 1 (n=13,132, 51%) and 2 (n=11,941, 46.7%) are more likely to be taken up by young subjects. The number of subjects with "deviant" behaviour increased until 2011 and after a decrease, the highest number of subjects concerned has been observed since 2015.

CONCLUSION

In view of the increase of subjects with "deviant" behaviour, it is necessary to make the medical community and patients aware on the risk of abuse of methylphenidate. The recent extension of the indication for ADHD in adults and the broadening of the conditions of prescription require increased vigilance.

Exacerbation of cancer pain after administering immune checkpoint inhibitor in a patient taking opioids: A case report

WHAT IS KNOWN AND OBJECTIVE

Clinical cases of attenuation of opioid analgesic effect by administration of immune checkpoint inhibitors has not been reported. We present a case of head and neck cancer under pain management with opioids, in which cancer pain was exacerbated after administration of nivolumab.

CASE SUMMARY

A male patient with head and neck cancer was hospitalized for the second-line treatment of nivolumab. He had complained of head and neck pain after admission, but the pain was especially worse after nivolumab administration. The dose of opioids was eventually increased by approximately 320% (morphine equivalent dose) compared to before administering nivolumab.

WHAT IS NEW AND CONCLUSION

When administering immune checkpoint inhibitors such as nivolumab in clinical practice, the possibility of attenuation of opioid analgesic effect should be considered.

Assessment of Stimulant Use and Cardiovascular Event Risks Among Older Adults

IMPORTANCE

Use of stimulants continues to increase among older adults for a variety of indications. An association between stimulant use and increased risk of cardiovascular (CV) events has been established among children and young adults, but few studies have explored the risk of CV events among older patients, a group with increased baseline risk.

OBJECTIVE

To evaluate the association between stimulant use and risk of CV events among older adults.

DESIGN, SETTING, AND PARTICIPANTS

This propensity score-matched cohort study, with 4 nonusers per 1 user, was conducted from July 1, 2017, to June 27, 2019, using data from population-based health care databases from Ontario, Canada, from January 1, 2002, to December 31, 2016. Included individuals were outpatients aged 66 years or older.

EXPOSURES

Initiation of a prescription stimulant.

MAIN OUTCOMES AND MEASURES

The primary outcome was a CV event, defined as a composite of emergency department visit or hospitalization for myocardial infarction, stroke or transient ischemic attack (TIA), or ventricular arrhythmia. Risk of CV event was assessed at 30 days, 180 days, and 365 days after initiation of stimulants from Cox proportional hazard models. A secondary analysis assessed each component of the primary outcome separately.

RESULTS

Among 6457 older adults who initiated a prescription stimulant (ie, the exposed group) and 24 853 older adults who did not initiate such treatment (ie, the unexposed group), the distribution of baseline patient characteristics was well balanced after matching (sex: 3173 [49.1%] men vs 12 112 [48.7%] men; standardized difference, 0.01; median [IQR] age: 74 [69-80] years vs 74 [69-80] years; standardized difference, 0.01). Within this cohort, there were 932 CV events during the 365-day follow-up (5.11 events per 100 person-years among individuals who initiated stimulants). In the primary analysis, stimulant initiation was associated with increased risk of CV events at 30 days (hazard ratio [HR], 1.4; 95% CI, 1.1-1.8) but not at 180 days (HR, 1.2; 95% CI, 0.9-1.6) or 365 days (HR, 1.0; 95% CI, 0.6 to 1.8). In the secondary analysis, stimulant initiation was associated with increased risk of ventricular arrhythmias (HR, 3.0; 95% CI, 1.1-8.7) and stroke or TIA (HR, 1.6; 95% CI, 1.1-2.1) at 30 days.

CONCLUSIONS AND RELEVANCE

This cohort study found that stimulant use was associated with an early increase in CV events among older adults with no association for long-term use.

Methylphenidate for Mild Cognitive Impairment: An Exploratory 3-Day, Randomized, Double-Blind, Placebo-Controlled Trial

Background: To evaluate the efficacy, safety and tolerability of methylphenidate (MPH) for cognitive function in older patients with mild cognitive impairment (MCI).

Methods: Male and female subjects aged 65 years and older with a clinical diagnosis MCI were included in an exploratory randomized, double-blind, placebo-controlled trial. Eligible subjects were assigned to either treatment with immediate-release MPH or placebo. The active compound was administered in an increasing-dose stepwise fashion, namely 10 mg MPH on day 1, 20 mg on day 2, and 30 mg on day 3. Subjects remained under observation for 4 h following drug administration and were monitored for changes in blood pressure and for adverse events. Cognitive outcome measures included the Montreal Cognitive Assessment (MoCA) and the Neurotrax Mindstreams computerized cognitive assessment battery.

Results: Of 17 subjects enrolled, 15 subjects completed the study, 7 in the active MPH group and 8 in the placebo group. The average age of the participants was 76.1 ± 6.6 years and 10 (66.7%) were men. Following the final dose a significant benefit on memory (predominantly non-verbal memory) was found in the MPH group. While 12 adverse events were reported, they were all rated as mild to moderate.

Conclusions: Our finding of modest beneficial effects of MPH on memory tests in older subjects with MCI in this exploratory study is of interest and should be investigated in further studies.

Methylphenidate for attention problems in epilepsy patients: Safety and efficacy

Children with attention deficit hyperactivity disorder (ADHD) have an increased risk of seizures, and children with epilepsy have an increased prevalence of ADHD. Adults with epilepsy often have varying degrees of attentional dysfunction due to multiple factors, including anti-seizure medications, frequent seizures, interictal discharges, underlying lesions, and psychiatric comorbidities. Currently, there are no approved medications for the treatment of epilepsy-related attentional dysfunction. Methylphenidate (MPH) is a stimulant, FDA-approved for the treatment of ADHD, and often used for ADHD in the setting of pediatric epilepsy. Large database and registry studies indicate safety of MPH in children with ADHD and epilepsy, with no significant effect on seizure frequency. Small single-dose and open-label studies suggest efficacy of MPH in adults with epilepsy-related attention deficits. Methylphenidate represents a possible treatment for attentional dysfunction due to epilepsy, but large, randomized, placebo-controlled, double-blinded studies are needed.

A pilot protocol to assess the feasibility of a virtual multiple crossover, randomized controlled trial design using methylphenidate in mild cognitive impairment

BACKGROUND

The conventional clinical trial design in Alzheimer's disease (AD) and AD-related disorders (ADRDs) is the parallel-group randomized controlled trial. However, in heterogeneous disorders like AD/ADRDs, this design requires large sample sizes to detect meaningful effects in an "average" patient. They are very costly and, despite many attempts, have not yielded new treatments for many years. An alternative, the multi-crossover, randomized control trial (MCRCT) is a design in which each patient serves as their own control across successive, randomized blocks of active treatment and placebo. This design overcomes many limitations of parallel-group trials, yielding an unbiased assessment of treatment effect at the individual level ("N-of-1") regardless of unique patient characteristics. The goal of the present study is to pilot a MCRCT of a potential symptomatic treatment, methylphenidate, for mild-stage AD/ADRDs, testing feasibility and compliance of participants in this design and efficacy of the drug using both standard and novel outcome measures suited for this design.

METHODS

Ten participants with mild cognitive impairment or mild-stage dementia due to AD/ADRDs will undergo a 4-week lead-in period followed by three, month-long treatment blocks (2 weeks of treatment with methylphenidate, 2 weeks placebo in random order). This trial will be conducted entirely virtually with an optional in-person screening visit. The primary outcome of interest is feasibility as measured by compliance and retention, with secondary and exploratory outcomes including cognition as measured by neuropsychological assessment at the end of each treatment period and daily brain games played throughout the study, actigraphy, and neuropsychiatric and functional assessments.

DISCUSSION

This pilot study will gauge the feasibility of conducting a virtual MCRCT for symptomatic treatment in early AD/ADRD. It will also compare home-based daily brain games with standard neuropsychological measures within a clinical trial for AD/ADRD. Particular attention will be paid to compliance, tolerability of drug and participation, learning effects, trends and stability of daily measures across blocks, medication carryover effects, and correlations between standard and brief daily assessments. These data will provide guidance for more efficient trial design and the use of potentially more robust, ecological outcome measures in AD/ADRD research.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT03811847 . Registered on 21 January 2019.

Differential Contribution of HIV-1 Subtypes B and C to Neurological Disorders: Mechanisms and Possible Treatments

With the introduction of combinatory antiretroviral therapy, patients infected with human immunodeficiency virus type 1 (HIV-1) can live much longer than before. However, the identification of HIV-associated neurocognitive disorder (HAND), especially HIV-associated dementia in 15-20% of patients infected with HIV-1, indicates additional complexity. These disorders turn out to be subtype dependent. Recently, many studies are ongoing trying to understand how the virus induces neuronal injury which could lead to neurological dysfunction. Most of these studies are focusing on the HIV-1 release of proteins such as Tat. However, the exact role of these proteins and their involvement in neuronal degeneration remains unidentified; this is especially true since viral proteins from different HIV-1 subtypes differ in their ability to cause neuronal damage. This review describes the role of different HIV-1 subtypes, identifies probable pathways involved in neuronal damage, the contribution of different HIV-1 subtypes to the progression of HAND, and potential treatments for HAND.

Current Agents in Development for Treating Behavioral and Psychological Symptoms Associated with Dementia

Behavioral and psychological symptoms associated with dementia are highly prevalent and are associated with an increased risk of institutionalization and mortality. Current pharmacological treatments for these symptoms include cholinesterase inhibitors, antipsychotics, and selective serotonin reuptake inhibitors. When used for treating behavioral and psychological symptoms associated with dementia, they are associated with limited efficacy and/or serious adverse events. As such, there has been extensive research into novel agents with varying mechanisms of action targeting behavioral and psychological symptoms associated with dementia. In this article, we present the results of a comprehensive literature search and review that evaluates current agents that have completed or are currently in clinical trials for treating behavioral and psychological symptoms associated with dementia as a primary outcome. We highlight novel agents from miscellaneous drug classes, such as dextromethorphan/quinidine, bupropion/dextromethorphan, lumateperone, deudextromethorphan/quinidine, methylphenidate and scyllo-inositol, and drugs from various therapeutic classes (including atypical antipsychotics, selective serotonin reuptake inhibitors, and cannabinoids) that have demonstrated promising results and were generally well tolerated. Future research with large appropriately powered studies using validated outcome measures for behavioral and psychological symptoms associated with dementia should be conducted to further establish the clinical utility of these agents.

Patterns and profiles of methylphenidate use both in children and adults

AIM

The aim of the present study was to characterize patterns of use of methylphenidate (MPH), a prescription stimulant medication recommended in the treatment of attention deficit hyperactivity disorder (ADHD) and of narcolepsy, in France, both in children and adults, over a 3-year period.

METHODS

Using the French General Health Insurance database, limited to two areas covering approximately 4 million individuals, we made up a cohort of incident MPH users between July 2010 and June 2013. Splitting them into distinct age groups (18-24, 25-49 and ≥50 years of age for adults and <6, 6-11 and 12-17 years of age for children), we established the characteristics of these populations at MPH initiation and during follow-up according to the duration of treatment, quantities dispensed and coprescription with central nervous system (CNS) drugs.

RESULTS

We included a cohort of 3534 incident users, involving 30 238 dispensings of MPH, leading to an annual rate of 29 incident users per 100 000 in 2013. Children (66% of new users) were characterized by long-term use of MPH with few comedications. The group of 25-49-year-old patients were dispensed MPH more frequently than other groups, had the highest mean dose and were more often coprescribed other CNS drugs. The ≥50 year-old group was more often coprescribed antidepressants and antiparkinsonian drugs.

CONCLUSIONS

Our pharmacoepidemiological study involving incident MPH users with a large number of characteristics showed different patterns of MPH use among children and adults. The results from the 25-49-year-old group suggested that MPH might be being used for medical conditions other than ADHD or narcolepsy in adults, and that it might be subject to misuse and/or abuse.

A research study review of effectiveness of treatments for psychiatric conditions common to end-stage cancer patients: needs assessment for future research and an impassioned plea

BACKGROUND

Rates of psychiatric conditions common to end-stage cancer patients (delirium, depression, anxiety disorders) remain unchanged. However, patient numbers have increased as the population has aged; indeed, cancer is a chief cause of mortality and morbidity in older populations. Effectiveness of psychiatric interventions and research to evaluate, inform, and improve interventions is critical to these patients' care. This article's intent is to report results from a recent review study on the effectiveness of interventions for psychiatric conditions common to end-stage cancer patients; the review study assessed the state of research regarding treatment effectiveness. Unlike previous review studies, this one included non-traditional/alternative therapies and spirituality interventions that have undergone scientific inquiry.

METHODS

A five-phase systematic strategy and a theoretic grounded iterative methodology were used to identify studies for inclusion and to craft an integrated, synthesized, comprehensive, and reasonably current end-product.

RESULTS

Psychiatric medication therapies undoubtedly are the most powerful treatments. Among them, the most effective (i.e., "best practices benchmarks") are: (1) for delirium, typical antipsychotics-though there is no difference between typical vs. atypical and other antipsychotics, except for different side-effect profiles, (2) for depression, if patient life expectancy is ≥4-6 weeks, then a selective serotonin reuptake inhibitor (SSRI), and if < 3 weeks, then psychostimulants or ketamine, and these generally are useful anytime in the cancer disease course, and (3) for anxiety disorders, bio-diazepams (BDZs) are most used and most effective. A universal consensus suggests that psychosocial (i.e., talk) therapy and spirituality interventions fortify the therapeutic alliance and psychiatric medication protocols. However, trial studies have had mixed results regarding effectiveness in reducing psychiatric symptoms, even for touted psychotherapies.

CONCLUSIONS

This study's findings prompted a testable linear conceptual model of co-factors and their importance for providing effective psychiatric care for end-stage cancer patients. The complicated and tricky part is negotiating patients' diagnoses while articulating internal intricacies within and between each of the model's co-factors. There is a relative absence of scientifically derived information and need for more large-scale, diverse scientific inquiry. Thus, this article is an impassioned plea for accelerated study and better care for end-stage cancer patients' psychiatric conditions.

Use of attention-deficit/hyperactivity disorder medication among older adults in Denmark

AIMS

Knowledge on the use of attention-deficit/hyperactivity disorder (ADHD) medication among older adults is limited. We hypothesized that ADHD medication is used off-label in adults aged ≥50 years as part of palliative care in e.g. cancer patients. The aim of this study was to describe the use of ADHD medication among adults aged ≥50 years in Denmark.

METHODS

Using the Danish health registries, we identified new users ≥50 years of ADHD medication during 2000-2012. We estimated the annual incidence of ADHD medication use and ADHD diagnoses. We described new users of ADHD medication according to co-medication, comorbidities and assessed the 1-year cumulative mortality rate. A posthoc analysis allowed us to include new users until 2015.

RESULTS

We identified 6690 new users of ADHD medication from 2000 to 2012. From 2000 to 2015 we observed an increase in the incidence of ADHD medication use from 12.5 to 30.3 per 100 000 person-years. However, the incidence rate decreased from 2010 to 2015. Throughout the study period, the incidence rate of ADHD diagnoses was low (overall prevalence among new users ≤2%). Opioids were the most frequent comedication used (used by 54%), while cancer was the most frequent diagnosis preceding treatment (prevalence of 52%). The 1-year cumulative mortality was 50%, primarily driven by patients with a preceding cancer diagnosis.

CONCLUSION

There was an increase in the incidence of ADHD medication use in adults aged ≥50 years from 2000-2010 and a decreasing incidence from 2010-2015. Our results suggest that ADHD medication is used off-label in older adults as part of palliative care.

Successful treatment of refractory cancer pain with morphine and ropivacaine: A case report

RATIONALE

Pain is one of the most common and distressing symptoms experienced by cancer patients. Cancer pain is a complex phenomenon with physical, psychological, social, and cognitive domains. Although opioids remain a cornerstone of cancer pain management, they are not effective in all patients. This case highlights the successful treatment of an opioid-refractory severe cancer pain crisis with ropivacaine infusion and subsequent rapid tapering of opioid dose.

PATIENT CONCERNS

This report illustrates the use of ropivacaine for cancer pain. A 62-year-old man with metastatic lung cancer was admitted to the hospital with uncontrolled chest-back and abdominal pain.

DIAGNOSES

The patient was diagnosed as refractory cancer pain.

INTERVENTIONS

Successful treatment with morphine and ropivacaine was performed to obtain longer opioid refractory severe cancer pain.

OUTCOMES

At 1, 3, and 6 months postoperative review, 70-75% relief of pain was achieved with overall activity was improved. The analgesic effect was stable during the 6-month follow-up period. No complications were reported during the follow-up period.

LESSONS

Our report demonstrates that ropivacaine is successful treatment for cancer pain in this case. It will supply us a novel navigation in cancer pain treatments. Meanwhile, this finding still needs additional study for confirmation.

Single Institute Experience With Methylphenidate and American Ginseng in Cancer-Related Fatigue

BACKGROUND

Single therapy with methylphenidate or American ginseng contributes to the reduction in cancer-related fatigue (CRF) with different pharmacologic mechanisms and is relatively safe. However, the safety and efficacy of treating CRF with methylphenidate and AG combination therapy is unknown.

AIM

The primary objective was to assess the clinical safety and the change in fatigue with numerical rating scale (NRS) on the Edmonton Symptom Assessment Scale (ESAS) after intervention with methylphenidate and AG combination therapy.

METHODS

We reviewed the electronic medical records of 857 patients seen in our Palliative Medicine outpatient clinic between February 1, 2015, and December 31, 2015. Fatigue was assessed by NRS on ESAS. Toxicity was reviewed on clinician's documents.

RESULTS

We identified 28 patients who were prescribed a combination of methylphenidate (10-40 mg/d) and AG (2000 mg/d). Ten patients did not comply with the combination therapy. Three patients had stage 2 adverse effects. Fifteen patients completed prescribed combination therapy per instructions. The mean time interval between pre- and postintervention follow-up was 30.5 days (standard deviation [SD]: 7.78). There was a significant reduction in the fatigue score (mean score 6.93-4.13) from the pre- to postscore records (mean: -2.8; SD: 1.61; P < .0002* [*refers to statistically significant]). Sixty percent of patients reported significant reduction in fatigue (cutoff value: ≥3; reduction in fatigue score from baseline: 80% ≥2, 60% ≥3, and 46.7% ≥4).

CONCLUSION

In our retrospective medical record review, the combination treatment of methylphenidate and AG had no discernible associated toxicities and showed potential clinical benefit in CRF.

Neurobehavioral Manifestations of Human Immunodeficiency Virus/AIDS: Diagnosis and Treatment

Behavioral disorders are common in persons infected with human immunodeficiency virus (HIV). The differential includes preexisting psychiatric diseases, substance abuse, direct effects of HIV infection, opportunistic infection, and the adverse effects of medical therapies. Many patients have more than one contributing or comorbid problem to explain these behavioral changes. The differential should always include consideration of psychosocial, genetic, and medical causes of disease. Treatment strategies must take into account the coadministration of antiretroviral therapy and the specific neurologic problems common in patients infected with HIV.

Suppression of Locomotor Activity in Female C57Bl/6J Mice Treated with Interleukin-1β: Investigating a Method for the Study of Fatigue in Laboratory Animals

Fatigue is a disabling symptom in patients with multiple sclerosis and Parkinson’s Disease, and is also common in patients with traumatic brain injury, cancer, and inflammatory disorders. Little is known about the neurobiology of fatigue, in part due to the lack of an approach to induce fatigue in laboratory animals. Fatigue is a common response to systemic challenge by pathogens, a response in part mediated through action of the pro-inflammatory cytokine interleukin-1 beta (IL-1β). We investigated the behavioral responses of mice to IL-1β. Female C57Bl/6J mice of 3 ages were administered IL-1β at various doses i.p. Interleukin-1β reduced locomotor activity, and sensitivity increased with age. Further experiments were conducted with middle-aged females. Centrally administered IL-1β dose-dependently reduced locomotor activity. Using doses of IL-1β that caused suppression of locomotor activity, we measured minimal signs of sickness, such as hyperthermia, pain or anhedonia (as measured with abdominal temperature probes, pre-treatment with the analgesic buprenorphine and through sucrose preference, respectively), all of which are responses commonly reported with higher doses. We found that middle-aged orexin^-/- mice showed equivalent effects of IL-1β on locomotor activity as seen in wild-type controls, suggesting that orexins are not necessary for IL-1β -induced reductions in wheel-running. Given that the availability and success of therapeutic treatments for fatigue is currently limited, we examined the effectiveness of two potential clinical treatments, modafinil and methylphenidate. We found that these treatments were variably successful in restoring locomotor activity after IL-1β administration. This provides one step toward development of a satisfactory animal model of the multidimensional experience of fatigue, a model that could allow us to determine possible pathways through which inflammation induces fatigue, and could lead to novel treatments for reversal of fatigue.

The dopamine imbalance hypothesis of fatigue in multiple sclerosis and other neurological disorders

Fatigue is one of the most pervasive symptoms of multiple sclerosis (MS), and has engendered hundreds of investigations on the topic. While there is a growing literature using various methods to study fatigue, a unified theory of fatigue in MS is yet to emerge. In the current review, we synthesize findings from neuroimaging, pharmacological, neuropsychological, and immunological studies of fatigue in MS, which point to a specific hypothesis of fatigue in MS: the dopamine imbalance hypothesis. The communication between the striatum and prefrontal cortex is reliant on dopamine, a modulatory neurotransmitter. Neuroimaging findings suggest that fatigue results from the disruption of communication between these regions. Supporting the dopamine imbalance hypothesis, structural and functional neuroimaging studies show abnormalities in the frontal and striatal regions that are heavily innervated by dopamine neurons. Further, dopaminergic psychostimulant medication has been shown to alleviate fatigue in individuals with traumatic brain injury, chronic fatigue syndrome, and in cancer patients, also indicating that dopamine might play an important role in fatigue perception. This paper reviews the structural and functional neuroimaging evidence as well as pharmacological studies that suggest that dopamine plays a critical role in the phenomenon of fatigue. We conclude with how specific aspects of the dopamine imbalance hypothesis can be tested in future research.

Psychopharmacology in cancer

Depression, anxiety, delirium, and other psychiatric symptoms are highly prevalent in the cancer setting, and pharmacological intervention is an important component in the overall psychosocial care of the patient. Psychopharmacology is also used as a primary or adjuvant treatment for the management of cancer-related symptoms stemming from the disease itself and/or its treatment, including sleep disturbance, loss of appetite, neuropathic pain, nausea, fatigue, and hot flashes. Psychiatrists, oncologists, and palliative care physicians working as members of a multidisciplinary team have the opportunity to target multiple symptoms that negatively affect a patient's quality of life with the strategic use of psychotropic medications when deemed appropriate. This article aims to review the indications for use of antidepressants, psychostimulants, anxiolytics, antipsychotics, and mood stabilizers in oncology. An updated review of the relevant literature is discussed and referenced in each section.

Anti-hypotensive treatment and endothelin blockade synergistically antagonize exercise fatigue in rats under simulated high altitude

Rapid ascent to high altitude causes illness and fatigue, and there is a demand for effective acute treatments to alleviate such effects. We hypothesized that increased oxygen delivery to the tissue using a combination of a hypertensive agent and an endothelin receptor A antagonist drugs would limit exercise-induced fatigue at simulated high altitude. Our data showed that the combination of 0.1 mg/kg ambrisentan with either 20 mg/kg ephedrine or 10 mg/kg methylphenidate significantly improved exercise duration in rats at simulated altitude of 4,267 m, whereas the individual compounds did not. In normoxic, anesthetized rats, ephedrine alone and in combination with ambrisentan increased heart rate, peripheral blood flow, carotid and pulmonary arterial pressures, breathing rate, and vastus lateralis muscle oxygenation, but under inspired hypoxia, only the combination treatment significantly enhanced muscle oxygenation. Our results suggest that sympathomimetic agents combined with endothelin-A receptor blockers offset altitude-induced fatigue in rats by synergistically increasing the delivery rate of oxygen to hypoxic muscle by concomitantly augmenting perfusion pressure and improving capillary conductance in the skeletal muscle. Our findings might therefore serve as a basis to develop an effective treatment to prevent high-altitude illness and fatigue in humans.

An evaluation of the pharmacokinetics of methylphenidate for the treatment of attention-deficit/ hyperactivity disorder

INTRODUCTION

Methylphenidate (MPH) plays a principal role in the multimodal treatment of attention-deficit/hyperactivity disorder (ADHD). Controlled studies have demonstrated an effective reduction in the core symptoms of the disorder following MPH therapy, although long-term studies also demonstrate that the therapeutic benefits dissipate in the absence of combined psychosocial interventions.

AREAS COVERED

This review article focuses on the pharmacological characteristics of MPH, examining its effects on brain metabolism and the neurotransmitter system. Neuropsychological and clinical effects of different immediate and extended release MPH formulations are discussed to aid clinicians in choosing the appropriate formulation. The drug's addictive potency and abuse potential is also discussed. Data came from a literature search of relevant studies performed using the PubMed database up to June 2013.

EXPERT OPINION

MPH is effective in the treatment of the core symptoms of ADHD. Considerable clinical expertise is required to identify an individually well-adapted dosage which will produce the optimal clinical effects with potential side effects minimized. Due to low adherence to medication, especially in adolescents, motivation to treatment and attentive clinical monitoring is mandatory, as is the consideration of risks of abuse or the presence of a comorbid addictive disorder.

The need for a multidisciplinary approach to pain management in advanced cancer: A clinical case

Advanced cancer patients are often affected by multiple complex symptoms brought about by persistent nociceptive stimuli and intense psychosocial distress. One such complex symptom, cancer pain, has continued to pose a challenge in medical management even though the concept of total pain was described several years ago by Cicely Saunders. Oftentimes, the application of a multidisciplinary approach is delayed after numerous opioid dose escalations and invasive procedures have been performed. The case presented here highlights the importance of timely multidisciplinary intervention and the use of an acute palliative care unit, which resulted in adequate pain control after multiple medical and invasive procedures that caused toxicities.

Attention-deficit/hyperactivity disorder in older adults: prevalence and possible connections to mild cognitive impairment

Attentional deficits are frequently seen in isolation as the presenting sign and symptom of neurodegenerative disease, manifest as mild cognitive impairment (MCI). Persistent ADHD in the geriatric population could well be misconstrued as MCI, leading to the incorrect assumption that such persons are succumbing to a neurodegenerative disease process. Alternatively, the molecular, neuroanatomic, or neurochemical abnormalities seen in ADHD may contribute to the development of de novo late life neurodegenerative disease. The present review examines the issue of causality vs confound regarding the association of ADHD with MCI, suggesting that both are tenable hypotheses.

[Androgen deprivation therapy in prostate cancer. Indication and systemic consequences]

Androgen deprivation therapy (ADT) is effective in prolonging the progression free survival of patients with symptomatic/metastatic prostate cancer (PC). The reduction of clinical symptoms of tumour disease and the reduction of tumour growth and metastatic dissemination is accompanied by systemic consequences of testosterone deficiency. These are hot flushes, fatigue due to reduction of muscular strength and muscle mass as well as anaemia. Moreover, patients develop cognitive impairment und depressive mood. Weight gain with insulin resistance, disturbances of lipid metabolism and gynecomastia are other effects of androgen deficiency. A decrease in bone mineral density may lead to an increased susceptibility to bone fractures. There are several options to reduce these side effects of ADT, e.g. physical activity, dietary supplementation, tailored pharmacological therapy and psychotherapy. The knowledge of these adjuvant treatment options, despite their palliative character, is relevant to optimize the quality of life of these patients.