Cost-effectiveness of dexamphetamine and methylphenidate for the treatment of childhood attention deficit hyperactivity disorder

Objective: To analyze from a health sector perspective the cost-effectiveness of dexamphetamine (DEX) and methylphenidate (MPH) interventions to treat childhood attention deficit hyperactivity disorder (ADHD), compared to current practice.

Method: Children eligible for the interventions are those aged between 4 and 17 years in 2000, who had ADHD and were seeking care for emotional or behavioural problems, but were not receiving stimulant medication. To determine health benefit, a meta-analysis of randomized controlled trials was performed for DEX and MPH, and the effect sizes were translated into utility values. An assessment on second stage filter criteria ('equity', 'strength of evidence', 'feasibility' and 'acceptability to stakeholders') is also undertaken to incorporate additional factors that impact on resource allocation decisions. Simulation modelling techniques are used to present a 95% uncertainty interval (UI) around the incremental costeffectiveness ratio (ICER), which is calculated in cost (in A$) per DALY averted.

Results: The ICER for DEX is A$4100/DALY saved (95% UI: negative to A$14 000) and for MPH is A$15 000/DALY saved (95% UI: A$9100-22 000). DEX is more costly than MPH for the government, but much less costly for the patient.

Conclusions: MPH and DEX are cost-effective interventions for childhood ADHD. DEX is more cost-effective than MPH, although if MPH were listed at a lower price on the Pharmaceutical Benefits Scheme it would become more cost-effective. Increased uptake of stimulants for ADHD would require policy change. However, the medication of children and wider availability of stimulants may concern parents and the community.

DNA damage in rats after treatment with methylphenidate.

Methylphenidate (MPH) is a widely prescribed psychostimulant for the treatment of attention-deficit hyperactivity disorder (ADHD). Recently, some studies have addressed the genotoxic potential of the MPH, but the results have been contradictory. Hence, the present study aimed to investigate the index of cerebral and peripheral DNA damage in young and adult rats after acute and chronic MPH exposure.

Efficacy and adverse effects of venlafaxine in children and adolescents with ADHD : a systematic review of non-controlled and controlled trials

Attention deficit hyperactivity disorder (ADHD) is a common psychiatric disorder in children and adolescents. Stimulants are commonly prescribed for ADHD management. There is clinical trial evidence that some medications with noradrenergic properties such as atomoxetine are effective. It is of theoretical and practical importance if other agents with noradrenergic properties display a comparable pattern of efficacy.
This paper is a systematic review of the efficacy and safety of venlafaxine for treating children and adolescents with ADHD. MEDLINE, Google scholar, Scopus, and Web of science (ISI) databases were electronically searched in July 2012, updated on November 2012. Time and language of publication were not exclusion criteria. Efficacy outcomes were assessed by a valid and reliable parent- and/or teacher-reported instrument to evaluate clinical symptoms. Adverse effects were also evaluated.

There were three uncontrolled trials and only two double blind controlled clinical trials. Venlafaxine appeared effective for treating ADHD. The rates of some adverse effects of venlafaxine were less than those documented for methylphenidate.

While one of the two small controlled trials did not find difference between venlafaxine ad methylphenidate, the other trial reported lower efficacy for venlafaxine. Headache, insomnia, and nausea were among the most common adverse effects.

This systematic review provides preliminary support that venlafaxine may have short term utility in treating ADHD in children and adolescents. However, before recommending venlafaxine for treatment, more robust and larger clinical trials, in particular providing evidence of its long-term efficacy, safety and tolerability are required.

Substance use to enhance academic performance among Australian university students

Use of substances to enhance academic performance among university students has prompted calls for evidence to inform education and public health policy. Little is known about this form of drug use by university students outside the US. A convenience sample of n= 1729 Australian university students across four universities responded to an exploratory on-line survey. Students were asked about their lifetime use of modafinil, prescription stimulants (e.g. methylphenidate), supplements (e.g. ginkgo biloba), illicit drugs (e.g. speed), relaxants (e.g. valium) and caffeine in relation to enhancing study performance. The results show that Australian students report using substances for study purposes at a higher lifetime rate than observed among US or German students. The main reasons for use were to improve focus and attention, and to stay awake. Use of substances to enhance study outcomes was correlated with faculty of study, attitude and use of other substances. These results point to the need to develop Australian evidence to guide policy or regulatory responses to student use of substances to enhance academic performance. © 2013 Elsevier Ltd.

Stimulants for depression: on the up and up?

The use of traditional psychostimulants (methylphenidate and dexamphetamine) and stimulant-like drugs (modafinil and armodafinil) for the treatment of depression is a growing concern given the lack of research evidence supporting their effectiveness. The current article describes the role of stimulants in treating depression--specifically their risks and benefits and their potential use alongside antidepressants. Clinically, the rapid amelioration of depressive symptoms with traditional psychostimulants is often dramatic but short-lived, and this suggests that they likely operate via different mechanisms to conventional antidepressants. More importantly, there is little evidence from randomised controlled trials supporting their efficacy in treating depression, although modafinil has been shown to be effective in reducing prominent depressive symptoms, such as fatigue. Research is urgently required to clarify psychostimulants' mechanisms of action and to evaluate their long-term benefits and risks in the treatment of major and bipolar depression. Ultimately, specificity of action needs to be determined to inform the sophisticated clinical use of psychostimulants in the management of depression. Until then they should only be prescribed if absolutely necessary, and even then their prescription should be facilitatory and time limited unless it is for investigational purposes.