Practical clinical trials in psychopharmacology: a systematic review

Designing clinically useful psychopharmacological trials: challenges and ways forward

The clinical guidelines that underpin the use of drugs for mental disorders are informed by evidence from randomised controlled trials (RCTs). RCTs are performed to obtain marketing authorisation from regulators. The methods used in these RCTs could be appropriate for early phases of drug development because they identify drugs with important harms and drugs that are efficacious for specific health problems and populations. RCTs done before marketing authorisation do not tend to address clinical questions that concern the effectiveness of a drug in heterogeneous and comorbid populations, the optimisation of drug sequencing and discontinuation, or the comparative benefits and harms of different drugs that could be used for the same health problem. This Review proposes an overview of some shortcomings of RCTs, at an individual level and at the whole portfolio level, and identifies some methods in planning, conducting, and carrying out analyses in RCTs that could enhance their ability to support therapeutic decisions. These suggestions include: identifying patient-important questions to be investigated by psychopharmacological RCTs; embedding pragmatic RCTs within clinical practice to improve generalisability to target populations; collecting evidence about drugs in overlooked populations; developing methods to facilitate the recruitment of patients with mental disorders and to reduce the number of patients who drop out, using specific methods; using core outcome sets to standardise the assessment of benefits and harms; and recording systematically serious objective outcomes, such as suicide or hospitalisation, to be evaluated in meta-analyses. This work is a call to address questions relevant to patients using diverse design of RCTs, thus contributing to the development of a patient-centred, evidence-based psychiatry.

Twenty years of progress in paediatric psychopharmacology: accomplishments and unmet needs

The systematic assessment of the efficacy and safety of psychiatric medications in children and adolescents started about 20 years ago. Since then, a considerable number of randomised clinical trials have been conducted, including also a series of publicly funded comparative effectiveness studies to evaluate the therapeutic benefit of medications relative to psychosocial interventions, alone or combined with medications. On the whole, these studies have been informative of the paediatric pharmacokinetics, efficacy and safety of the most commonly used psychotropics. As a consequence, a number of meta-analyses have been conducted that have documented both the benefits and harms of the most common medication groups, such as stimulants, antidepressants and antipsychotics. Evidence-based practice guidelines have been produced, and clinicians can now better estimate the therapeutic value and the risk of treatment, at least at the group mean level. However, most clinical trials have been conducted in research settings, and this limits the generalisability of the results. There is a need for evaluating treatment effects under usual practice conditions, through practical trials. The ongoing debate about the proper role of pharmacotherapy in child mental health can be advanced by comparative effectiveness research to assess the benefit/risk ratio of pharmacotherapy vis-à-vis alternative treatment modalities. In addition, analyses of large population databases can better inform on the impact of early treatment on important distal outcomes, such as interpersonal functioning, social and occupational status, quality of life and risk for disability or mortality. Thus far, paediatric psychopharmacology has been mostly the application to children of medications that were serendipitously discovered and developed for adults. By focusing on the neurobiological mechanisms of child psychopathology, it may be possible to identify more precise pharmacological targets and arrive at a truly developmental psychopharmacology.

Stimulants and Pediatric Cardiovascular Risk

OBJECTIVE

Concerns about serious cardiovascular (CV) events among stimulant-treated youth have led to clinical and policy debates. Accordingly, several population-based empirical studies have assessed the risk of CV events in children and adolescents treated with stimulants. The main objective of this review was to summarize findings and to evaluate the strengths and weaknesses of these population-based studies. In addition, we discuss the CV monitoring and policy implications for a clinically focused audience.

METHODS

A computerized literature search of Medline and PsycINFO was conducted for the calendar years 1990-2015 to identify population-based studies assessing stimulant treatment-emergent CV events in youth. Additional reports, peer-reviewed or gray literature, for example, government reports, were also included.

RESULTS

Nine population-based studies (one case-control and eight retrospective cohort designs) were included in this review. The case-control study compared sudden unexplained death cases to age-matched controls (motor vehicle passenger deaths) with respect to prior stimulant use and found a significant association (odds ratio = 7.4 [95% CI: 1.4-74.9]). By contrast, most retrospective cohort studies assessed the risk of serious CV events (i.e., sudden death, myocardial infarction, and stroke) and did not find an association with current stimulant exposure. The absolute rate for these serious events was low, but other data support risk. For example, cardiac-related emergency department visits showed a 20% increased risk for current stimulant users compared with nonusers in one study, and another study showed a 64% and 90% increased risk for concurrent use of stimulants with antidepressants and antipsychotics, respectively. Similarly, in another study, compared with nonusers, stimulant users had twofold greater odds of CV-related inpatient or outpatient services.

CONCLUSION

In the face of mixed results from population-based safety studies, this review supports the inclusion of baseline and ongoing monitoring of cardiac status to assure a favorable benefit risk profile for stimulant users, particularly in concomitant regimens with antipsychotics and antidepressants.

The Challenge of Reproducibility and Accuracy in Nutrition Research: Resources and Pitfalls

Inconsistent and contradictory results from nutrition studies conducted by different investigators continue to emerge, in part because of the inherent variability of natural products, as well as the unknown and therefore uncontrolled variables in study populations and experimental designs. Given these challenges inherent in nutrition research, it is critical for the progress of the field that researchers strive to minimize variability within studies and enhance comparability between studies by optimizing the characterization, control, and reporting of products, reagents, and model systems used, as well as the rigor and reporting of experimental designs, protocols, and data analysis. Here we describe some recent developments relevant to research on plant-derived products used in nutrition research, highlight some resources for optimizing the characterization and reporting of research using these products, and describe some of the pitfalls that may be avoided by adherence to these recommendations.