PubMed Health⌕ Search

Biomedical subjects

Ian C K Wong

Publications and source records attributed to Ian C K Wong.

17 recordsLinked to original sources
PubMed2026

Psychiatric and neurological predictors of early ADHD medication discontinuation across the lifespan: a multinational study.

BACKGROUND: Early discontinuation of attention-deficit/hyperactivity disorder (ADHD) medication is common and linked to worse outcomes. Identifying clinical predictors could aid personalised treatment yet evidence is inconsistent across ages and countries/regions. OBJECTIVE: Investigate psychiatric and neurological comorbidity as predictors of early ADHD medication discontinuation in new ADHD medication users across age groups, sex and countries/regions. METHODS: Using health records from eight countries/regions, we identified 1 000 411 (44% female) new ADHD medication users (2011-2020). Discontinuation was defined as a ≥180 day gap between dispensations. We examined 23 indicators of psychiatric or neurological comorbidity, severity and psychotropic medication use. Associations were estimated using Cox regression, pooled with random-effects meta-analyses and stratified by age-at-initiation and sex. FINDINGS: Discontinuation rates varied widely (children 19%-61%, adolescents 37%-68%, young adults 52-67%, adults 38%-68%). In pooled analyses, earlier discontinuation in children was predicted by intellectual disability, autism and use of psychotropic medications (HR range 1.32-1.51), while conduct/oppositional defiant disorder (CD/ODD) was protective (HR 0.83, 95% CI 0.73 to 0.94). In adolescents, no indicators remained statistically significant after multiple-testing control. In young adults, CD/ODD (HR 1.42, 95% CI 1.30 to 1.55), and in adults, schizophrenia (HR 1.25, 95% CI 1.09 to 1.44) and tic disorders (HR 1.27, 95% CI 1.11 to 1.46) predicted earlier discontinuation. Statistical heterogeneity was substantial, largely driven by US estimates. In meta-analyses excluding the USA, additional associations emerged. For example, in children, OCD and anxiety disorders predicted earlier discontinuation, while eating disorders and antidepressants/anxiolytics were protective in adults. Associations with schizophrenia, tic disorders and CD/ODD were no longer significant. Country-specific analyses showed similar association patterns, except in the USA, Hong Kong and the UK. Sex differences were limited. CONCLUSIONS: Children with neuropsychiatric comorbidity and related comedication are more likely to discontinue ADHD medication early, whereas few consistent predictors were seen from adolescence onwards. Marked cross-country variation, particularly in the USA, points to system-level influences on treatment patterns. CLINICAL IMPLICATIONS: Improving ADHD medication persistence will require consideration of healthcare context and age-specific strategies, including close monitoring for children with complex neuropsychiatric profiles, and consideration of broader factors in adolescents and adults, where clinical predictors were limited.

Humans↗
PubMed2006

Systematic review of medication errors in pediatric patients.

OBJECTIVE: To systematically locate and review studies that have investigated the incidence of medication errors (MEs) in pediatric inpatients and identify common errors. METHODS: A systematic search of studies related to MEs in children was performed using the following databases: MEDLINE (1951-April 2006), EMBASE (1966-April 2006), Pharm-line (1978-April 2006), International Pharmaceutical Abstracts (1970-April 2006), Cumulative Index to Nursing and Allied Health Literature (1982-April 2006), and British Nursing Index (1994-April 2006). Studies of the incidence and nature of MEs in pediatrics were included. The title, abstract, or full article was reviewed for relevance; any study not related to MEs in children was excluded. RESULTS: Three methods were used to detect MEs in the studies reviewed: spontaneous reporting (n = 10), medication order or chart review (n = 14), or observation (n = 8). There was great variation in the definitions of ME used and the error rates reported. The most common type of ME was dosing error, often involving 10 times the actual dose required. Antibiotics and sedatives were the most common classes of drugs associated with MEs; these are probably among the most common drugs prescribed. CONCLUSIONS: Interpretation of the literature was hindered by variation in definitions employed by different researchers, varying research methods and setting, and a lack of theory-based research. Overall, it would appear that our initial concern about MEs in pediatrics has been validated; however, we do not know the actual size of the problem. Further work to determine the incidence and causes of MEs in pediatrics is urgently needed, as well as evaluation of the best interventions to reduce them.

Child↗
PubMed2006

Interventions of hospital pharmacists in improving drug therapy in children: a systematic literature review.

Medicines' management or pharmaceutical care in paediatric patients is particularly demanding, mainly because the majority of available drugs have been developed for use in adults. As a result, in children, drugs are often unlicensed or used off-label, suitable formulations or appropriate strengths are lacking, and drugs have to be extemporaneously prepared, liquids and injections diluted, and tablets split. These factors increase the likelihood of medication errors and may lead to a reduction in drug effect. Age-specific changes in pharmacokinetics and pharmacodynamics further complicate drug therapy in children. All these challenges provide unique opportunities for pharmacists to improve the quality of care for paediatric patients. We conducted a systematic literature review examining whether the interventions of hospital pharmacists improve drug therapy in children. Several medical and pharmaceutical databases were searched systematically to identify articles investigating hospital pharmacists' interventions that were intended to improve drug therapy in children. Inclusion criteria were English language, primary research papers and studies in which clinical pharmacists contributed directly to patient care. Exclusion criteria were reviews, editorials, questionnaire studies, modelling studies, letters and studies only available in abstract form. This systematic search identified 18 articles documenting the role of a clinical hospital pharmacist in paediatric care. These articles were divided into the following groups based on study type: (i) studies documenting interventions made by pharmacists and their role in inpatients; (ii) articles presenting the outcomes of a satellite pharmacy; and (iii) articles examining pharmacist involvement in paediatric outpatient clinics. No randomised study comparing pharmacist interventions with standard care was found. In conclusion, although it was difficult to compare the various studies identified because of the different settings, design, duration, size, methodology and definition, all these studies highlighted the importance of hospital pharmacists to medicines' management in paediatric patients. On the basis of this review, we can conclude that pharmacist reviewing of medication charts is very important in identifying medication errors; hence, it is likely to be the most effective method of improving drug therapy in children.

Adverse Drug Reaction Reporting Systems↗
PubMed2005

When do children convert from liquid antiretroviral to solid formulations?

BACKGROUND: Liquid formulations are usually regarded as the gold standard in paediatric formulation; but sometimes, liquid formulations have stability and taste problems as well as being inconvenient for travelling. Therefore, for the management of long-term illness, some older children, parents and clinicians would prefer to use solid formulations. However, there is a lack of studies to investigate the age at which children are converted from liquid to solid formulations. OBJECTIVES: (1) To investigate the age range at which children convert from liquid antiretroviral drug formulations to solid formulations, the formulations are abacavir, didanosine, lamivudine, stavudine, and zidovudine. (2) To calculate how long children stay on each of five UK liquid formulations (retention time) and factors affecting the retention times of the above liquid formulations. METHOD: This was a retrospective medical records survey at Great Ormond Street Hospital for Children, London, United Kingdom. Patients' treatment details were entered into SPSS for Windows v. 11.0 and the retention times for the above liquid formulations were calculated i.e., from initiation of the liquid treatment to conversion to solid preparation. The retention times of different preparations were then compared using Cox regression analysis. RESULTS: A total of 92 patients are included in the analysis. The overall average age at conversion was 7.3 years (95% CI 6.3-8.2). Patients on stavudine were more likely to switch to the corresponding solid dose form than the other four medicines (P < 0.001); more than 50% of patients on stavudine switched to solid formulation after nine months of treatment, however, less than 25% of patients on other formulations switched during the same period. CONCLUSION: Children taking antiretroviral liquid preparations change to solid dose forms at approximately seven years of age. However, for stavudine, children are more likely to take the solid form at an earlier age.

Age Factors↗
PubMed2005

The potential of UK clinical databases in enhancing paediatric medication research.

The research potential of many UK clinical databases is not being realized. A recent report published by the Royal College of Paediatrics & Child Health stated that there is a need to build research capacity and support in the area of paediatric pharmacology, with specific emphasis on the use of clinical databases. This article presents the databases available in the UK for medication research and gives some examples of paediatric studies conducted. The databases discussed include the Prescription Pricing Authority database, the General Practice Research Database, IMS Health databases (Medical Data Index, MIDAS Prescribing Insights, Disease-Analyser-Mediplus) and the Yellow Card Scheme. Other databases such as the Medicines Monitoring Unit (MEMO) and the Scottish Primary Care Computer System also have research potential in paediatric pharmacoepidemiology, but their population sizes are relatively small.

Adolescent↗
PubMed2005

Poor formulation information in published pediatric drug trials.

OBJECTIVE: The International Conference on Harmonisation Steering Committee recommends that appropriate formulations be used in pediatric drug trials. However, a lack of formulation research and/or economic constraints means that appropriate formulations are not always used. It is important for investigators who report the results of pediatric drug trials to provide sufficient information on the formulation and method of administration to ensure that the results can be reproduced in other clinical studies (reliability) and, more important, implemented in clinical practice (validity). The objective of this study was to evaluate whether pediatric formulation information was adequately reported in recent published trials of oral medicines that included children who were younger than 12 years. METHODS: Studies that were published between July 2002 and June 2004 in 10 highly cited journals (5 pediatric and 5 general medicine) were hand-searched and data were extracted independently by 2 reviewers according to a protocol. Papers that reported oral medication studies that included children who were younger than 12 years were classified as containing adequate, some, or no information on drug formulation. RESULTS: Of 3992 papers reviewed, 76 fulfilled the inclusion criteria. Only 28 (37%) gave adequate information for the study to be reproduced accurately, and 20 (26%) did not state the formulation used. When the formulation was reported, only 37 (49%) studies used a pediatric formulation (liquid, chewable tablet, granules). No significant differences between pediatric and general medical journals were seen, and no single journal consistently met the criteria for adequate information. CONCLUSION: Highly cited journals seem to permit inadequate formulation information in pediatric drug trials that they publish, impairing their validity and reliability. Authors should provide full formulation information in all pediatric clinical trial reports.

Child↗
PubMed2005

Effects of the Committee on Safety of Medicines advice on antidepressant prescribing to children and adolescents in the UK.

BACKGROUND: Psychotropic medication prescribing for children and adolescents rose significantly between 2000 and 2002, including antidepressant prescribing. In 2003, the Committee on Safety of Medicines (CSM) advised against using venlafaxine or any selective serotonin receptor inhibitor (SSRI), with the exception of fluoxetine, for childhood and adolescent depression. The aim of this study was to compare the prevalence and incidence of children and adolescents who were prescribed antidepressants in UK primary care, before and after the CSM advice on antidepressant prescribing. We also compared paediatric antidepressant prescribing trends from Mediplus data with national antidepressant prescribing trends in England from the Prescription Pricing Authority (PPA). METHODS: The Disease Analyzer-Mediplus database contains anonymised primary care records for about 3 million patients. Eligible patients were aged or=1 antidepressant prescription between 2000 and 2004. Antidepressants were grouped according to the CSM advice and the British National Formulary. Prevalence and incidence were calculated. The prevalences of 2000, 2002 and 2004 were compared using a Chi-squared test. PPA data on antidepressant prescribing rates were compared with paediatric antidepressant prescribing rates from Mediplus. RESULTS: 5,718 children and adolescents received a total of 25,542 prescriptions between 2000 and 2004. The median number of prescriptions per patient was two (interquartile range 1-5). Common indications included depression and anxiety. Antidepressant prevalence increased from 2000 to 2002 (from 5.4 to 6.6 patients per 1,000 people), with a rise in the number of patients prescribed venlafaxine and SSRIs. However, between 2002 and 2004 there was a decrease in antidepressant prevalence (from 6.6 to 5.7 per 1,000). The prevalence of CSM-contraindicated antidepressants (citalopram, escitalopram, fluvoxamine, paroxetine, sertraline and venlafaxine) declined by a third (from 3.1 to 2.0 per 1,000), but there was no change in fluoxetine prevalence (from 2.1 to 2.3 per 1,000). The number of patients prescribed tricyclic antidepressants dropped marginally (from 2.0 to 1.7 per 1,000). Incidences followed the same trends as the prevalences, but there was a 48% reduction in the incidence of CSM-contraindicated antidepressants between 2002 and 2004. National antidepressant prescribing trends increased; paediatric prescribing trends were similar to national trends between 2000 and 2003; however, there was a 27% reduction in the paediatric prescribing rate of CSM-contraindicated antidepressants between 2002 and 2004. CONCLUSION: Since 2003, fewer children and adolescents have been prescribed antidepressants in primary care. However, fluoxetine and non-SSRI antidepressant prevalences have not risen, implying that they are not prescribed as alternative treatments. This study shows that the CSM advice has had a significant effect in reversing the rising prevalence of antidepressant prescribing to children and adolescents in primary care.

Adolescent↗
PubMed2004

Incidence and nature of dosing errors in paediatric medications: a systematic review.

In paediatric medicine, drug doses are usually calculated individually based on the patient's age, weight and clinical condition. Therefore, there are increased opportunities for, and a relatively high risk of, dosing errors in this setting. Consequently, a systematic literature review using several databases was conducted to investigate the incidence and nature of dosing errors in children; 16 studies were found to be relevant. Eleven of the 16 studies found that dosing errors are the most common type of medication error, three of the remaining studies found it to be the second most common type. This review of published research on medication errors therefore suggests that dosing errors are probably the most common type of error in the paediatric population. In addition, there was a great variation in the error rates reported; this is likely to be due to the differences in the medication error definitions and methodologies employed. For example, the dosing error rate determined using spontaneous reporting ranges from 0.03 per 100 admissions in the UK to 2 per 100 admissions in the US. Extrapolating this, if the under-reporting rate is about 1 in 100, then the true incidence would be around 50,000 paediatric dosing errors per year in England. The information available shows that dosing errors are not uncommon and that 10-fold overdoses caused by calculation errors have led to serious consequences. There is an urgent need to develop methods to reduce medication errors in children and dosing errors should be the first priority.

Adolescent↗
PubMed2004

Use of selective serotonin reuptake inhibitors in children and adolescents.

Depression is a serious condition, associated with considerable morbidity and mortality; selective serotonin reuptake inhibitors (SSRIs) were commonly used in its treatment in child and adolescent psychiatry until recently. In the wake of the recent UK Committee on Safety of Medicines (CSM) advice, we conducted a rapid review of current available information on SSRIs and suicidality (suicidal ideation, self-harm and suicide attempt) in children and adolescents from clinical trials and epidemiological studies. There is insufficient safety information from the randomised controlled trials to confirm a definite association between SSRIs and suicidality. Furthermore, analysis of suicide and antidepressant prescribing trends in three countries and a large case-control study do not support the hypothesis that there is a link between use of SSRIs and death caused by suicide. Regulatory agencies and the media should have strict guidelines for the management of information relating to the treatment of this condition so that clinicians can make properly informed decisions. We suggest clinical guidelines for managing depression in children and adolescents. SSRIs should not be considered for use as first-line treatment in mild or moderate depression of childhood, where psychological interventions such as cognitive behaviour therapy or interpersonal therapy are the mainstay. SSRIs should be considered when there is severe depression that does not respond to psychological interventions; when the child is suicidal and is admitted as an inpatient, is severely depressed or has bipolar depression despite adequate doses of mood-stabilisation agents; or when the child or family prefers pharmacotherapy to psychological interventions and gives informed consent. Local bodies of clinicians or peer groups should agree protocols and acceptable guidelines, taking into consideration the type of patients being assessed, the availability of nonpharmacological intervention, and the benefit-risk ratio of the pharmacological intervention. It is important that parents (and patients when possible) be given accurate information regarding the current controversy over SSRI prescribing. More research into the use of SSRIs in childhood depression is urgently required.

Adolescent↗
PubMed2003

Cost-effectiveness analysis of high-dose omeprazole infusion as adjuvant therapy to endoscopic treatment of bleeding peptic ulcer.

BACKGROUND: Intravenous administration of proton pump inhibitors after endoscopic treatment of bleeding peptic ulcers has been shown to decrease the rate of recurrent bleeding and the need for subsequent surgery. Yet there is a relative lack of formal assessment of this practice. The aim of this study was to examine the cost-effectiveness of this therapy by using standard pharmacoeconomic methods. METHODS: The present study was performed in conjunction with a randomized controlled clinical trial that included 232 patients who received either omeprazole (80 mg intravenous bolus followed by infusion at 8 mg/hour for 72 hours) or placebo after hemostasis was achieved endoscopically. A cost-effectiveness analysis was performed to evaluate the different outcomes of the trial. All related direct medical costs were identified from patient records. Cost-effectiveness ratios were calculated. RESULTS: Analysis by the Kolmogorov-Smirnov test showed that the direct medical cost in the omeprazole group was lower than that for the placebo group. Cost-effectiveness ratios for omeprazole and placebo groups were, respectively, HK$ 28,764 (US$ 3688) and HK$ 36,992 (US$ 4743) in averting one episode of recurrent bleeding in one patient after initial hemostasis was achieved endoscopically. CONCLUSIONS: Intravenous administration of high-dose omeprazole appears to be a cost-effective therapy in reducing the recurrence of bleeding and need for surgery in patients with active bleeding ulcer after initial hemostasis is obtained endoscopically.

Adult↗
PubMed2003

A feasibility study for recording of dispensing errors and near misses' in four UK primary care pharmacies.

Medication errors can occur at the prescribing, transcription, dispensing and administration stage of drug therapy. However, publication of the Organisation with a Memory (OWAM) by the Department of Health in the UK has raised awareness of the need for pharmacies to collect information about dispensing errors and near misses, which occur within an organisation. Such information provides valuable insights into the vulnerabilities of dispensing procedures and identifies areas for improvement in dispensing systems The main aim of this study was to investigate the feasibility of a self-reporting system for dispensing errors and near misses in primary care (community) pharmacies. It was also to identify the types of errors or near misses commonly encountered in community pharmacies. A data collection form was designed and modified for use after a pilot study. Four community pharmacies volunteered to participate in this feasibility study. The data collection was conducted in two phases each of 4 weeks' duration. Any dispensing errors and near misses that occurred during the study periods were recorded by the pharmacy staff in a standard data collection form. A focus group discussion was held with the dispensing staff of participating pharmacies to identify and evaluate the feasibility of the reporting system. Out of a total of 51 357 items dispensed during the two phases of the study, 39 dispensing errors (0.08%) and 247 near misses (0.48%) were detected. The results show that near misses occurred six times more often than dispensing errors, indicating the importance of final checking in pharmacies. The most common types of dispensing errors or near misses appeared to be incorrect strength of medication, followed by incorrect drug, incorrect quantity, incorrect dosage form and incorrect label. Feedback during the focus group discussion indicated that the outcome of the self-reporting scheme was more important than the incidence of errors or near misses. Participating pharmacies also agreed that the self-reporting scheme used was feasible and they would continue using the scheme although some incentives would be helpful. The quantitative results of this study and the qualitative feedback from the participating pharmacies indicate that the self-reporting scheme used is practical and feasible.

Data Collection↗