The use of methylphenidate for cognitive decline associated with HIV disease

Effect of armodafinil on cognition in patients with HIV/AIDS and fatigue

Fatigue and cognitive impairment are common in HIV+ adults and may occur independently or be causally linked. This study examined whether alleviation of fatigue with armodafinil in a placebo-controlled double-blind 4-week trial had an effect on cognitive function among those with and without mild neuropsychological impairment at baseline. Sixty-one patients completed a standard battery of neuropsychological tests at study entry and Week 4: A total of 33 were randomized to armodafinil and 28 to placebo. While there was a significant effect of active medication on fatigue, cognitive performance measured by a global change score did not differ between treatment groups, or in those on active treatment with or without mild neuropsychological impairment.

Therapeutics in Huntington's Disease

OPINION STATEMENT: There is no specific treatment for Huntington's disease (HD). Its many symptoms of motor, psychiatric, and cognitive deterioration are managed with symptomatic relief, rehabilitation, and support. The only drug approved by the US Food and Drug Administration (FDA) for the treatment of HD is an antichoreic agent, tetrabenazine, but this drug is used sparingly because of uneasiness regarding its propensity to cause depression and suicidality in this population, which is already at risk for these complications. Neuroleptics are still first-line treatments for chorea accompanied by comorbid depression and/or behavioral or psychotic symptoms, as is often the case. Psychiatric features, which have a significant impact on a patient's professional and personal life, often become the major focus of management. In addition to neuroleptics, commonly used medications include antidepressants, mood stabilizers, anxiolytics, and psychostimulants. In contrast, few treatment options are available for cognitive impairment in HD; this remains an important and largely unmet therapeutic need. HD patients typically lack insight into their disease manifestations, failing to recognize their need for treatment, and possibly even arguing against it. Multipurpose medications are employed advantageously to simplify the medication regimen, so as to facilitate compliance and not overwhelm the patient. For example, haloperidol can be prescribed for a patient with chorea, agitation, and anorexia, rather than targeting each symptom with a different drug. This approach also limits the potential for adverse effects, which can be difficult to distinguish from the features of the disease itself. With HD's complexity, it is best managed with a multidisciplinary approach that includes a movement disorders specialist, a genetic counselor, a mental health professional, a physical therapist, and a social worker for support and coordination of services. As the disease progresses, there may be need for other specialists, such as a speech and occupational therapist, a nutritionist for weight loss, and ultimately, a palliative care specialist.

Modafinil effects on cognitive function in HIV+ patients treated for fatigue: a placebo controlled study

Both mild cognitive impairment and fatigue are common among people with HIV/AIDS. This study examined the efficacy of modafinil for HIV+ patients who sought treatment for fatigue in a placebo-controlled double-blind 4-week trial. A battery of standard neuropsychological tests was administered at study entry and Week 4, and change in performance was compared for 59 patients receiving modafinil versus 44 patients receiving placebo. A significant effect on fatigue was observed. In addition, cognitive performance, as measured by a global change score, improved more in the modafinil than in the placebo group although the effect was not specific to any cognitive domain.

Chemotherapy and Cognition: Effects, Potential Mechanisms, and Management

The development of novel chemotherapeutic agents and advances in treatment technique have improved survival for patients diagnosed with some forms of cancer, but treatments are not always site specific and may place normal tissues at risk. The central nervous system (CNS) is susceptible to treatment effects and complaints of memory loss and generalized cognitive decline are common among cancer patients. Despite the frequency of subjective patient complaints, studies evaluating the cognitive abilities of patients have inconsistently reported chemotherapy-related declines. On careful review of the literature, discrepant findings across studies (some documenting chemotherapy-related cognitive declines and others failing to detect such changes) may be attributed to differences in methodology. Most studies have been retrospective in design, omit pretreatment assessment of function, use small or heterogeneous samples, use inappropriate measures to assess cognition, and fail to incorporate control subjects. Though rare to date, prospective, randomized, longitudinal studies that incorporate pretreatment comprehensive neuropsychological assessment are necessary to define the severity and pattern of treatment-related change. Building on a foundation of solid science, future studies may identify subgroups of patients susceptible to significant chemotherapy-related cognitive decline. Once these groups are identified and the mechanisms underlying the decline are elucidated, attention may be turned to the development of treatments that may optimize cognitive function and improve patient quality of life.

Human immunodeficiency virus and depression in primary care: a clinical review

BACKGROUND

Human immunodeficiency virus (HIV)-infected individuals are at increased risk of developing depression. Depressive syndromes in these patients pose a challenge both diagnostically and therapeutically. These syndromes reflect both the presence of preexisting mood disorders and the development of depressive syndromes subsequent to HIV infection.

DATA SOURCES

A search of the literature to 2005 was performed using the PubMed and Ovid search engines. English- and Portuguese-language articles were identified using the following keywords: HIV or AIDS and depression, mental illness, suicide, fatigue, psychiatry, and drug interactions. Additional references were identified through bibliography reviews of relevant articles.

DATA SYNTHESIS

The clinical presentation and differential diagnosis of depressive symptoms in HIV illness and the role of HIV in the development of these conditions are reviewed. Management issues including suicide assessment and treatment options are then discussed, and potentially important pharmacokinetic interactions are reviewed.

CONCLUSIONS

Individuals with HIV show higher rates of depression. This phenomenon may be due to a preexisting psychiatric disorder or to the HIV infection. Untreated depression symptoms may lead to non-compliance with drug regimens or increased high-risk behaviors. Given the adverse sequelae of untreated depressions in HIV illness, identification and management of depression are integral components of comprehensive HIV care.

Molecular basis for interactions of HIV and drugs of abuse

In certain populations around the world, the HIV pandemic is being driven by drug-abusing populations. Mounting evidence suggests that these patient populations have accelerated and more severe neurocognitive dysfunction compared with non-drug-abusing HIV-infected populations. Because most drugs of abuse are central nervous system stimulants, it stands to reason that these drugs may synergize with neurotoxic substances released during the course of HIV infection. Clinical and laboratory evidence suggests that the dopaminergic systems are most vulnerable to such combined neurotoxicity. Identifying common mechanisms of neuronal injury is critical to developing therapeutic strategies for drug-abusing HIV-infected populations. This article reviews 1) the current evidence for neurodegeneration in the setting of combined HIV infection and use of methamphetamine, cocaine, heroin or alcohol; 2) the proposed underlying mechanisms involved in this combined neurotoxicity; and 3) future directions for research. This article also suggests therapeutic approaches based on our current understanding of the neuropathogenesis of dementia due to HIV infection and drugs of abuse.

Strategies for managing cancer-related fatigue syndrome: a rehabilitation approach

Although technologic advances and insights into the mechanisms of cancer and cancer treatments have resulted in hope of increased survival and even cure in many cancer populations, parallel efforts to promote quality of life through a commitment to rehabilitation and aggressive palliation have lagged. Recent studies have demonstrated fatigue to be the most distressing phenomenon experienced by cancer patients. This article examines fatigue from a rehabilitation perspective. Application of innovations in therapeutic exercise training, diet therapy, sleep therapy, cognitive therapy, and pharmacologic therapy and their attendant rationales are discussed. From clinical as well as research perspectives of palliation and rehabilitation, the manifestations of fatigue are better appreciated if fatigue is conceptualized as a syndrome, namely, cancer-related fatigue syndrome (CRFS). Experience of CRFS by cancer patients, regardless of their diagnosis, stage of disease, treatment regimen, or age, influences all aspects of quality of life and aggravates the experience of other distressing symptoms such as pain, nausea, and dyspnea. Understanding the underlying mechanisms for energy loss and gain, as well as the relationship between the right amount and type of activity and sleep, can lead toward more effective and innovative rehabilitation programs. Development of research based clinical interventions in these areas holds promise for significant improvement in functioning and quality of life for cancer survivors and may constitute valuable rehabilitative techniques that can be adjunctive to standard therapies.

Immediate neurocognitive effects of methylphenidate on learning-impaired survivors of childhood cancer

PURPOSE

To test if methylphenidate (MPH) has an objective beneficial effect on immediate performance on tests of neurocognitive functions among learning-impaired survivors of childhood acute lymphoblastic leukemia (ALL) and malignant brain tumors (BT).

PATIENTS AND METHODS

From July 1, 1997 through December 31, 1998, 104 long-term survivors of childhood ALL or a malignant BT completed neurocognitive screening for learning impairments and concurrent problems with sustained attention. Eligibility criteria for the MPH trial included an estimated intelligence quotient greater than 50, academic achievement in the 16(th) percentile or lower for age in reading, math, or spelling, and an ability to sustain attention on a computerized version of the Conners' Continuous Performance Test (CPT) in the 16(th) percentile or lower for age and sex. Of the 104, 32 (BT, n = 25; ALL, n = 7) were eligible on the basis of these a priori criteria for a randomized, double-blinded, placebo-controlled trial of MPH. The patients ingested a placebo (lactose) or MPH (0.6 mg/kg; 20 mg maximum) and repeated selected portions of the screening battery 90 minutes later.

RESULTS

Compared to the 17 patients randomized to the placebo group, the 15 patients randomized to the MPH group had a significantly greater improvement on the CPT for sustained attention (errors of omission, P =.015) and overall index (P =.008) but not for errors of commission (indicative of impulsiveness) nor reaction times. A trend for greater improvement in the MPH group on a measure of verbal memory failed to reach statistical significance. No trend was observed for MPH effectiveness in improving learning of a word association task. No significant side effects from MPH were observed.

CONCLUSION

MPH resulted in a statistically significant improvement on measures of attention abilities that cannot be explained by placebo or practice effects.

Estrogen protects against the synergistic toxicity by HIV proteins, methamphetamine and cocaine

BACKGROUND

Human immunodeficiency virus (HIV) infection continues to increase at alarming rates in drug abusers, especially in women. Drugs of abuse can cause long-lasting damage to the brain and HIV infection frequently leads to a dementing illness. To determine how these drugs interact with HIV to cause CNS damage, we used an in vitro human neuronal culture characterized for the presence of dopaminergic receptors, transporters and estrogen receptors. We determined the combined effects of dopaminergic drugs, methamphetamine, or cocaine with neurotoxic HIV proteins, gp120 and Tat.

RESULTS

Acute exposure to these substances resulted in synergistic neurotoxic responses as measured by changes in mitochondrial membrane potential and neuronal cell death. Neurotoxicity occurred in a sub-population of neurons. Importantly, the presence of 17beta-estradiol prevented these synergistic neurotoxicities and the neuroprotective effects were partly mediated by estrogen receptors.

CONCLUSION

Our observations suggest that methamphetamine and cocaine may affect the course of HIV dementia, and additionally suggest that estrogens modify the HIV-drug interactions.

Methylphenidate: its pharmacology and uses

Methylphenidate is a commonly used medication in the United States. This central nervous system stimulant has a mechanism of action distinct from that of amphetamine. The Food and Drug Administration has approved methylphenidate for the treatment of attention-deficit/hyperactivity disorder and narcolepsy. Treatment with methylphenidate has been advocated in patients with traumatic brain injury and stroke, cancer patients, and those with human immunodeficiency virus infection. Placebo-controlled trials have documented its efficacy as an adjunctive agent in the treatment of depression and pain. This article reviews the current understanding of the mechanism of action and efficacy of methylphenidate in various clinical conditions.

Pharmacotherapy of HIV dementia

OBJECTIVE

To review the clinical presentation and management of cognitive impairment associated with central nervous system HIV type 1 (HIV-1) infection.

DATA SOURCES

A MEDLINE search pertaining to HIV-related dementia (HIV-D) and pharmacologic management was performed. Additional literature was obtained from reference lists of the identified articles.

STUDY SELECTION AND DATA EXTRACTION

All clinical trials and case reports evaluating pharmacologic efficacy in terms of clinical response, cerebrospinal fluid (CSF) changes, and neuropathology were considered for inclusion. Selection was not restricted by study design because most information consists of open uncontrolled trials and case reports.

DATA SYNTHESIS

HIV-D is characterized by a triad of disturbances in cognition, motor performance, and behavior in adults. Children present with developmental delay, cognitive impairment, poor brain growth, and other neurologic symptoms. The exact pathophysiologic mechanisms of HIV-D are not known. Numerous pharmacologic agents (e.g., nucleoside reverse transcriptase inhibitors, pentoxifylline, nitroglycerin, memantine, nimodipine, peptide T) are under investigation for management of HIV-D. Zidovudine is the most thoroughly investigated medication, with patients developing HIV-D less frequently and showing improvement on neuropsychological, CSF, and neuropathologic evaluations. Sustained response to zidovudine lasts 6 months to 1 year and optimal response is achieved at higher, but less tolerated, dosages. HIV-D patients frequently have comorbid psychiatric disorders requiring psychopharmacologic agents and are sensitive to the adverse effects of these medications.

CONCLUSIONS

HIV-D is a devastating complication of HIV-1 infection. Zidovudine is the therapy of choice for prevention and management of cognitive impairment in symptomatic HIV-infected patients and patients with AIDS. Recommendations for other medications cannot be made secondary to lack of data. The management of HIV-D may include multiple agents as more data become available regarding combination therapy. Well-designed controlled trials are needed to evaluate the efficacy of established treatments and investigational medications in the management of HIV-D.

Use of stimulants in the medically ill

This article discusses the use of psychostimulants, such as dextroamphetamine, methylphenidate, and pemoline, in a variety of illnesses, including depression in the medically ill, cancer, HIV, and AIDS. The chemistry and pharmacology, side effects, drug interactions, dosing, and abuse potential also are reviewed.