Bibliometric studies, which involve the use of statistical methods, are increasingly being used for research assessment. A bibliometric analysis was conducted to evaluate the publication pattern of methaemoglobinaemia research output at the global level based on the Scopus database. We analysed selected documents with "methemoglobinemia", or "methaemoglobinaemia" as a part of the title and reported the following parameters: trends of publication output, country of publication, journal pattern, collaborative measures, citations pattern, and institute productivity. A total of 1770 articles were published worldwide. The time trend for the number of articles showed an increase after 2000. The highest number of articles related to methaemoglobinaemia was from the USA (24.8 %), followed distantly by the UK (4.5 %), India (3.7 %), and France (3.7 %). No data related to methaemoglobinaemia were published from 152 countries. The total number of citations at the date of data collection was 10,080, with an average of 5.7 citations per document. The USA and UK had the highest h-index of 31 and 14, respectively, and six countries had an h-index of 9-14. It is notable that Canada was ranked eighth in the number of publications but fourth in h-index and India was ranked third in the number of publications but eighth in h-index. Furthermore, Canada produced the most internationally collaborated papers out of the total number of publications for each country (16.1 %), followed by the UK (13.9 %). This bibliometric analysis provides data contributing to a better understanding of the methaemoglobinaemia research field. The number of publications on methaemoglobinaemia increased significantly after 2000. The USA was the most productive country as measured by total publications. The USA and UK achieved the highest h-index in the field of methaemoglobinaemia research, signifying a higher quality of research than other countries.
Toxicology in Malaysia has experienced rapid development and made great progress in education and research in conjunction with economic development in Malaysia over the past two decades.
BACKGROUND: Bibliometric studies are increasingly being used for research assessments. Bibliometric indicators involve the application of statistical methods to scientific publications to obtain the bibliographics for each journal. The main objective of this study was to conduct a bibliometric evaluation of Human & Experimental Toxicology retrieved from the Scopus database.
METHODS: This study obtained data from Scopus published from 1 January 2003 till 31 December 2012. The keywords entered in Scopus to accomplish the objective of this study were 'Human', 'Experimental' and 'Toxicology' as 'Source Title'. Research productivity was evaluated based on a methodology developed and used in other bibliometric studies by analysing (a) total and trends in Human & Experimental Toxicology contributions in research between 2003 and 2012; (b) Human & Experimental Toxicology authorship patterns and productivity; (c) collaboration patterns; and (d) the citations received by the publications.
RESULTS: There were 1229 research articles published in Human & Experimental Toxicology. Of the articles included, 947 (77.1%) were original articles and 104 (8.5%) were review articles. The Hirsch-index of the retrieved documents was 35. The largest number of publications in Human & Experimental Toxicology was from the United States (19.6%), followed by India (12.8%) and Turkey (10.9%). The total number of citations was 9119, with a median (interquartile range) of 3 (1-9) in 6797 documents. The highest median (interquartile range) number of citations was 8 (2.7-12.7) for France, followed by 7.5 (2-22.5) for Iran and 6 (3-13.5) for the United Kingdom. The country most often citing articles that were published in Human & Experimental Toxicology was the United States, which made citations in 1508 documents, followed by India with citations in 792 documents.
CONCLUSION: The documents in Human & Experimental Toxicology focus principally on original data, with very few review articles. Review articles tend to have higher citation rates than original articles, and hence, the editors and authors of Human & Experimental Toxicology might usefully promote the submission of reviews in the future to improve the impact of the journal.
KEYWORDS: Bibliometric; Scopus; citations; human and experimental toxicology
OBJECTIVES: The objectives of this study were 1) to obtain information regarding the prescribing pattern of nonsteroidal anti-inflammatory drugs (NSAIDs) in the primary care setting at a Malaysian university, 2) to determine the prevalence and types of potential NSAID prescription related problems (PRPs), and 3) to identify patient characteristics associated with exposure to these potential PRPs.
METHODS: We retrospectively collected data from 1 academic year using the electronic medical records of patients in the University Sains Malaysia (USM) primary care system. The defined daily dose (DDD) methodology and the anatomical therapeutic chemical (ATC) drug classification system were used in the analysis and comparison of the data. Statements representing potential NSAID PRPs were developed from authoritative drug information sources. Then, algorithms were developed to screen the databases for these potential PRPs. Descriptive and comparative statistics were used to characterize DRPs.
RESULTS: During the study period, 12,470 NSAID prescriptions were prescribed for 6,509 patients (mean ± SD = 1.92 ± 1.83). This represented a prevalence of 35,944 per 100,000 patients, or 36%. Based on their DDDs, mefenamic acid and diclofenac were the most prescribed NSAIDs. 573 potential NSAID-related PRPs were observed in a cohort of 432 patients, representing a prevalence of 6,640 per 100,000 NSAIDs users, or 6.6% of all NSAID users. Multivariate logistic regression analysis revealed that patients with a Malay ethnic background (p < 0.001), members of the staff (p < 0.001), having 4 or more prescribers (p < 0.001) or having 2 - 3 prescribers (p = 0.02), and representing 4 or more long-term therapeutic groups (LTTGs) (p < 0.001) or 2 - 3 LTTGs (p < 0.001) were significantly associated with an increased chance of exposure to potential NSAID related PRPs.
CONCLUSIONS: This is the first study in Malaysia that presents data on the prescribing pattern of NSAIDs and the characteristics of potential NSAID-related PRPs. The prevalence of potential NSAID-related PRPs is frequent in the primary care setting. Exposure to these PRPs is associated with specific sociodemographic and health status factors. These results should help to raise the awareness of clinicians and patients about serious NSAID PRPs.
Study site: University Sains Malaysia (USM) primary care system.
WHAT IS KNOWN AND OBJECTIVE: Drug-drug interactions (DDIs) cause considerable morbidity and mortality worldwide and may lead to hospital admission. Sophisticated computerized drug information and monitoring systems, more recently established in many of the emerging economies, including Malaysia, are capturing useful information on prescribing. Our aim is to report on an investigation of potentially serious DDIs, using a university primary care-based system capturing prescription records from its primary care services.
METHODS: We retrospectively collected data from two academic years over 20 months from computerized databases at the Universiti Sains Malaysia (USM) from users of the USM primary care services.
RESULTS AND DISCUSSION: Three hundred and eighty-six DDI events were observed in a cohort of 208 exposed patients from a total of 23,733 patients, representing a 2-year period prevalence of 876·4 per 100,000 patients. Of the 208 exposed patients, 138 (66·3%) were exposed to one DDI event, 29 (13·9%) to two DDI events, 15 (7·2%) to three DDI events, 6 (2·9%) to four DDI events and 20 (9·6%) to more than five DDI events. Overall, an increasing mean number of episodes of DDIs was noted among exposed patients within the age category ≥70 years (P=0·01), an increasing trend in the number of medications prescribed (P<0·001) and an increasing trend in the number of long-term therapeutic groups (P<0·001).
WHAT IS NEW AND CONCLUSION: We describe the prevalence of clinically important DDIs in an emerging economy setting and identify the more common potentially serious DDIs. In line with the observations in developed economies, a higher number of episodes of DDIs were seen in patients aged ≥70 years and with more medications prescribed. The easiest method to reduce the frequency of DDIs is to reduce the number of medications prescribed. Therapeutic alternatives should be selected cautiously.
There has been recent interest in combining antiplatelets, angiotensin-converting enzyme inhibitors (ACEIs) and statins in primary and secondary ischaemic stroke prevention. This observational study was performed to evaluate the impact of adding ACEIs and/or statins to antiplatelets on post-stroke in-hospital mortality. Ischaemic stroke patients attending a hospital in Malaysia over an 18-month period were evaluated. Patients were categorized according to their vital status at discharge. Data included demographic information, risk factors, clinical characteristics and previous medications with particular attention on antiplatelets, ACEIs and statins. In-hospital mortality was compared among patients who were not taking antiplatelets, ACEIs or statins before stroke onset versus those who were taking antiplatelets alone or in combination with either ACEIs, statins or both. Data analysis was performed using SPSS version 15. Overall, 637 patients met the study inclusion criteria. After controlling for the effects of confounders, adding ACEIs or statins to antiplatelets significantly decreased the incidence of death after stroke attack by 68% (p = 0.036) and 81% (p = 0.010), respectively, compared to patients on antiplatelets alone or none of these medications. Additionally, the addition of both ACEIs and statins to antiplatelet medication resulted in the highest reduction (by 94%) of the occurrence of death after stroke attack (p < 0.001). Our results suggest that adding ACEIs and/or statins to antiplatelets for patients at risk of developing stroke, either as a primary or as a secondary preventive regimen, was associated with a significant reduction in the incidence of mortality after ischaemic stroke than antiplatelets alone. These results might help reduce the rate of ischaemic stroke morbidity and mortality by enhancing the application of specific therapeutic and management strategies for patients at a high risk of acute stroke.
The availability of antidotes may be considered essential and lifesaving in the management of certain poisonings. Surveys carried out in a number of countries have demonstrated inadequate availability of a variety of poisoning antidotes.
The present study examines the relationship between the dose of acetaminophen reported to have been ingested by patients and the occurrence of serum acetaminophen levels above the 'possible toxicity' line in patients presenting at the hospital after acetaminophen overdose. The prognostic value of patient-reported dosage cut-offs of 8, 10 and 12 g was determined.
Acute poisoning is a common medical emergency in Malaysia. Life can be saved if the patient is diagnosed properly and receives the appropriate treatment such as gastrointestinal decontamination techniques and resources to increase poison elimination according to clinical guidelines at a reasonable time. The aims of this study were to determine the availability of decontamination, elimination enhancement, and stabilization resources for the management of acute toxic exposures and poisonings in accident and emergency departments in Malaysia, and to compare the availability of such facilities among various types of hospitals. A comparative, descriptive cross-sectional study was conducted using a structured questionnaire. Seventy-four (58.3%) out of the targeted 127 hospitals replied and completed the questionnaire. The availabilities of most items related to stabilization resources were far better in general hospitals compared to district hospitals with specialists and district hospitals without specialists. These items were mechanical ventilators (p = 0.011), non-invasive positive pressure ventilators (0.024), pacemakers (p = 0.019), and transcutaneous cardiac pacing (p < 0.001). The availability of decontamination resources varied substantially with hospital type. Nevertheless, these differences did not reach statistical significance in any of the cases, whereas sodium sulphate, sorbitol, and polyethylene glycol were almost never available. The availabilities of most items related to elimination enhancement resources were far better in general hospitals and district hospitals with specialists compared to district hospitals without specialists. These items were haemodialysis (p = 0.046), haemoperfusion (p = 0.002), haemofiltration (p = 0.002), acid diuresis (p = 0.04), peritoneal dialysis (p < 0.001), and exchange transfusion (p < 0.001). Most Malaysian hospitals have certain important immediate interventions such as gastrointestinal decontamination techniques and resources to increase poison elimination. The availabilities of most facilities were far better in the general hospitals. Coordination between the National Poison Centre in Malaysia and hospitals should be established regarding the emergency facilities for effective management of poisoning cases in each hospital in order to direct the poisoned patients to the hospital where the appropriate management resources is available.
BACKGROUND: Patients with diabetes mellitus (DM) are more prone to develop atherosclerotic complications including stroke. Moreover, as a primary and secondary prevention of stroke, antiplatelet therapy is recommended by clinical guidelines for patients with DM.
AIMS: This study aimed to determine the prevalence of antiplatelet therapy use prior to current stroke in diabetic ischemic stroke patients, to examine the factors associated with the use of this important therapy and to assess the impact of the previous use of antiplatelet therapy on ischemic stroke outcomes.
METHODS: An observational study of diabetic acute ischemic stroke patients attending a Malaysian hospital during a 1-year period was carried out. Demographic information, risk factors, previous antiplatelet use and variables used to assess stroke outcomes were collected from medical records.
RESULTS: Overall, 295 diabetic stroke patients were analyzed. The prevalence of previous antiplatelet use among diabetic patients was 38.3%. The independent variables associated with the previous use of antiplatelet medication were previous stroke attack (p < 0.001) and ischemic heart disease (p < 0.001). Better outcomes as measured by a minor Glasgow Coma Scale at admission (p = 0.032), and a higher Modified Barthel index at discharge (p = 0.027) were observed among patients on previous antiplatelet therapy.
CONCLUSION: Our data suggest that antiplatelet therapy is under prescribed among such diabetic stroke patients, particularly in primary prevention. Effective methods to increase antiplatelet use and to enhance the adherence of clinical practice guidelines should be considered at the national and community level.
BACKGROUND: The prescription of contraindicated drugs is a preventable medication error, which can cause morbidity and mortality. Recent data on the factors associated with drug contraindications (DCIs) is limited world-wide, especially in Malaysia.
AIMS: The objectives of this study are 1) to quantify the prevalence of DCIs in a primary care setting at a Malaysian University; 2) to identify patient characteristics associated with increased DCI episodes, and 3) to identify associated factors for these DCIs.
METHODS: We retrospectively collected data from 1 academic year using computerized databases at the Universiti Sains Malaysia (USM) from patients of USM's primary care. Descriptive and comparative statistics were used to characterize DCIs.
RESULTS: There were 1,317 DCIs during the study period. These were observed in a cohort of 923 patients, out of a total of 17,288 patients, representing 5,339 DCIs per 100,000 patients, or 5.3% of all patients over a 1-year period. Of the 923 exposed patients, 745 (80.7%) were exposed to 1 DCI event, 92 (10%) to 2 DCI events, 35 (3.8%) to 3 DCI events, 18 (2%) to 4 DCI events, and 33 patients (3.6%) were exposed to 5 or more DCI events. The average age of the exposed patients was 30.7 ± 15 y, and 51.5% were male. Multivariate logistic regression analysis revealed that being male (OR = 1.3; 95% CI = 1.1 - 1.5; p < 0.001), being a member of the staff (OR = 3; 95% CI = 2.5 - 3.7; p < 0.001), having 4 or more prescribers (OR = 2.8; 95% CI = 2.2 - 3.6; p < 0.001), and having 4 or more longterm therapeutic groups (OR = 2.3; 95%CI = 1.7 - 3.1; p < 0.001), were significantly associated with increased chance of exposure to DCIs.
DISCUSSION AND CONCLUSIONS: This is the first study in Malaysia that presents data on the prevalence of DCIs. The prescription of contraindicated drugs was found to be frequent in this primary care setting. Exposure to DCI events was associated with specific socio-demographic and health status factors. Further research is needed to evaluate the relationship between health outcomes and the exposure to DCIs.
Acetaminophen is one of the most commonly encountered medications in self-poisoning, with a high rate of morbidity. The prevalence and characteristics of acetaminophen intoxication associated with long hospital stay in patients are not well defined.
Statins can reduce the risk of stroke in at-risk populations and improve survival after acute ischemic stroke (AIS) among patients with previous statin use. This study aimed to investigate the impact of statin use before AIS onset on in-hospital mortality and identify the factors related to in-hospital mortality among patients with and without previous statin use. A retrospective cohort study of all patients with AIS attending hospital from June 1, 2008 to December 31, 2008. Data were collected from medical records including demographic information, diagnostic information, risk factors, previous statin use, and vital discharge status. Chi-square, Fisher's exact tests, student's t-test, and Mann-Whitney U test, whatever appropriate, were used to test the significance between the variables, and multiple logistic regression was used to identify factors associated with in-hospital mortality. Altogether, 386 patients with AIS were studied, of which 113 (29.3%) had a documented previous statin use. A total of 62 (16.1%) patients with AIS died in hospital. In-hospital mortality was significantly lower among previous statin users (P = 0.013). The presence of atrial fibrillation (AF) increased in-hospital mortality among patients with or without previous statin use. The independent predictors for in-hospital mortality among AIS patients without previous statin use were the presence of diabetes mellitus (P = 0.047), AF (P = 0.045), and renal impairment (P < 0.001). The prophylactic administration of statins significantly reduces post-AIS in-hospital mortality. Furthermore, the identification of predictors of in-hospital mortality might reduce death rates and enhance the application of specific therapeutic and management strategies to patients at a high risk of dying.
Intravenous N-acetylcysteine (IV-NAC) is usually regarded as a safe antidote to acetaminophen overdose. However, during infusion of the loading dose, adverse drug reactions such as a headache may occur. The objectives of this study were to investigate the prevalence of headache in patients presenting to hospital after acetaminophen overdose and to determine which clinical findings are most predictive of headache among these patients. This is a retrospective cohort study of hospital admissions for acute acetaminophen overdose that was conducted over a period of 4 years from January 1, 2005 to December 31, 2008. Demographic data, clinical characteristics, and predictors of headache were analyzed. spss 15 was used for data analysis. Two-hundred and fifty-five patients were studied; their mean age was 23.1 ± 1.6; 83.9% of them were women and 14.9% had a headache during hospitalization. Headache among patients was significantly associated with IV-NAC administration (P = 0.001), intentional ingestion of drug (P = 0.04), acetaminophen concentration above 'possible toxicity' treatment line (P = 0.04), a high acetaminophen concentration (P = 0.04), and a long hospital stay (P = 0.03). Multiple logistic regression showed a significant risk factor for headache in patients administered IV-NAC (P = 0.04). We recorded a high frequency of headache in patients with acute acetaminophen overdose in our geographical area. This study suggests that among those patients, the use of IV-NAC is associated with an increased risk of headache.
Acetaminophen overdose may be accompanied by electrolyte disturbances. The basis for electrolyte change appears to be due to increased fractional urinary electrolyte excretion.
BACKGROUND: Angiotensin-converting enzyme inhibitors (ACEIs), antiplatelets (APs), and statin are increasingly being prescribed for ischemic stroke prevention.
OBJECTIVES: The objective of the study was to examine whether previous combination therapy of ACEI with AP and/or statin has additive effect compared with ACEI alone on functional outcome after ischemic stroke. Furthermore, factors associated with improving functional outcome were investigated.
METHODS: Ischemic stroke patients attending a Malaysian hospital in 2008 were categorized according to Barthel Index at discharge. Favorable outcome was defined as Barthel Index of 75 or greater. Data included demographic information, clinical characteristics, and previous medications with particular attention to ACEI, AP, and statin.
RESULTS: Overall, 505 patients were included. Variables associated with good functional outcome were younger age (P = 0.002), first-ever attack (P = 0.016), lacunar (P = 0.015) or posterior circulation infarct stroke subtype (P = 0.034), minor Glasgow Coma Scale (P < 0.001), and previous use of ACEI alone or combined with AP and/or statin (P = 0.002). Using ACEI alone as the reference for ACEI + AP, ACEI + statin, or ACEI + AP + statin combinations, there was no significant difference among combinations on improving functional outcome (P = 0.852).
CONCLUSIONS: Prestroke use of ACEI either alone or combined with AP and/or statin was associated with better functional outcome. Previous use of ACEI in combination with AP and/or statin did not significantly differ from ACEI alone in their effect on outcome. Our study provides a potential rationale for optimizing the use of ACEI among individuals at risk of developing ischemic stroke.
Identifying indices of poor prognosis at first presentation after acetaminophen poisoning is the key to both improving clinical care and determining targets for intervention. This study intended to document the prevalence, clinical characteristics and predictors of vomiting and to investigate the relationship between episodes of vomiting at first hospital presentation and outcome in acetaminophen poisoning. This retrospective cohort study included patients who attended the emergency department and were admitted within 24 hr of acetaminophen ingestion. The study was conducted over a period of 5 years from 1 January 2004 to 31 December 2008. Parametric and non-parametric tests were used to test differences between groups depending on the normality of the data. SPSS 15 was used for data analysis. Data from 291 patients were included. Vomiting was present in 65.3% of patients with acetaminophen poisoning at the time of first presentation. Multiple logistic regression showed that significant risk factors for vomiting were present among patients who reported an ingested dose of acetaminophen ≥10 g (p < 0.001) and a latency time of more than 8 hr (p = 0.030). Overall, an increasing trend in prothrombin time (p = 0.03), serum bilirubin (p < 0.001), serum creatinine (p = 0.005), serum potassium (p < 0.001), length of hospital stay (p < 0.001) and the prevalence of patients who had a serum acetaminophen level above a 'possible toxicity' treatment line (p = 0.001) were associated with an increased number of episodes of vomiting. In conclusion, vomiting was common among patients with acetaminophen poisoning. This study suggests that an increase in episodes of vomiting at first presentation appears to be an important risk marker of subsequent nephrotoxicity and hepatotoxicity.
To investigate the relationship between different types of adverse drug reaction (ADR) and late time to N-acetylcysteine (NAC) infusion in patients presenting to the hospital with acetaminophen overdose.
Intravenous N-acetylcysteine is usually regarded as a safe antidote. However, during the infusion of the loading dose, different types of adverse drug reactions (ADR) may occur. The objective of this study was to investigate the relation between the incidence of different types of ADR and serum acetaminophen concentration in patients presenting to the hospital with acetaminophen overdose. This is a retrospective study of patients admitted to the hospital for acute acetaminophen overdose over a period of 5 years (1 January 2004 to 31 December 2008). Parametric and non-parametric tests were used to test differences between groups depending on the normality of the data. SPSS 15 was used for data analysis. Of 305 patients with acetaminophen overdose, 146 (47.9%) were treated with intravenous N-acetylcysteine and 139 (45.6%) were included in this study. Different types of ADR were observed in 94 (67.6%) patients. Low serum acetaminophen concentrations were significantly associated with cutaneous anaphylactoid reactions but not other types of ADR. Low serum acetaminophen concentration was significantly associated with flushing (p < 0.001), rash (p < 0.001) and pruritus (p < 0.001). However, there were no significant differences in serum acetaminophen concentrations between patients with and without the following ADR: gastrointestinal reactions (p = 0.77), respiratory reactions (p = 0.96), central nervous reactions (p = 0.82) and cardiovascular reactions (p = 0.37). In conclusion, low serum acetaminophen concentrations were associated with higher cutaneous anaphylactoid reactions. Such high serum acetaminophen concentrations may be protective against N-acetylcysteine-induced cutaneous ADR.