COVID-19 is a current global pandemic. However, comprehensive global data analyses for its mortality risk factors are lacking. The current investigation aimed to assess the predictors of death among COVID-19 patients from worldwide open access data. Methods: A total of 828 confirmed cases of COVID-19 with definite outcomes were retrospectively identified from open access individual-level worldwide data. Univariate followed by multivariable regression analysis were used to evaluate the association between potential risk factors and mortality. Results: Majority of the patients were males 59.1% located in Asia 69.3%. Based on the data, older age (adjusted odds ratio (aOR), 1.079; 95% confidence intervals (95% CI), 1.064-1.095 per year increase), males (aOR, 1.607; 95% CI, 1.002-2.576), patients with hypertension (aOR, 3.576; 95% CI, 1.694-7.548), diabetes mellitus (aOR, 12.234; 95% CI,), and patients located in America (aOR, 7.441; 95% CI, 3.546-15.617) were identified as the risk factors of mortality among COVID-19 patients. Conclusions: Males, advanced age, hypertension patients, diabetes mellitus patients, and patients located in America were the independent risk factors of death among COVID-19 patients. Extra attention is required to be given to these factors and additional studies on the underlying mechanisms of these effects.

Background and Objective. Clozapine is a second-generation antipsychotic drug that is considered the most effective treatment for refractory schizophrenia. Several clozapine population pharmacokinetic models have been introduced in the last decades. Thus, a systematic review was performed (i) to compare published pharmacokinetics models and (ii) to summarize and explore identified covariates influencing the clozapine pharmacokinetics models. Methods. A search of publications for population pharmacokinetic analyses of clozapine either in healthy volunteers or patients from inception to April 2019 was conducted in PubMed and SCOPUS databases. Reviews, methodology articles, in vitro and animal studies, and noncompartmental analysis were excluded. Results. Twelve studies were included in this review. Clozapine pharmacokinetics was described as one-compartment with first-order absorption and elimination in most of the studies. Significant interindividual variations of clozapine pharmacokinetic parameters were found in most of the included studies. Age, sex, smoking status, and cytochrome P450 1A2 were found to be the most common identified covariates affecting these parameters. External validation was only performed in one study to determine the predictive performance of the models. Conclusions. Large pharmacokinetic variability remains despite the inclusion of several covariates. This can be improved by including other potential factors such as genetic polymorphisms, metabolic factors, and significant drug-drug interactions in a well-designed population pharmacokinetic model in the future, taking into account the incorporation of larger sample size and more stringent sampling strategy. External validation should also be performed to the previously published models to compare their predictive performances.

Cyclosporine is a primary drug in transplant immunosuppression regimens. It has a narrow therapeutic index and variable pharmacokinetic behavior. This study aimed to develop a population pharmacokinetic model of cyclosporine in Malaysian renal transplant recipients as well as to evaluate the performances of different methodsfor handling missing doses. A total of 2804 concentrationts predose and 2 hours after doses were collected retrospectively from 113 renal transplant patients on cyclosporine in Penang General Hospital. Model structure and pharmacokinetic parameters were estimated using nonlinear mixed-effects modeling software. Missing doses were handled using different methods to evaluate their performance. Covariate analysis was performed using stepwise forward addition (P < .05) followed by backward elimination (P < .001). Prediction-corrected visual predictive check and sampling-importance resampling methods were used to validate the final model. A 1-compartment model with first-order absorption and elimination best fitted the data. All methods to handle missing doses performed well with the missing dose method being superior to other methods and thus was applied in the final model. Cyclosporine clearance (CL/F) was estimated as 15.1 L/h, and volume of distribution (V/F) was 108 L. Postoperative time, sex, and calcium channel blockers were identified as significant covariates on CL/F, whereas sex and cholesterol level were identified as significant covariates on V/F. This is the first population pharmacokinetic model developed in Malaysian renal transplant patients using a large sample with an evaluation of different methods to handle missing doses in less informative conventional therapeutic drug-monitoring data.

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Clozapine remains the drug of choice for resistant schizophrenia. However, its dose-response relationship is still controversial. The current investigation aimed to develop a repeated time-to-positive symptoms improvement following the onset of clozapine treatment in Malaysian schizophrenia spectrum disorder patients. Data from patients’ medical records in the Psychiatric Clinic, Penang General Hospital, were retrospectively analyzed. Several parametric survival models were evaluated using nonlinear mixed-effect modeling software (NONMEM 7.3.0). Kaplan–Meier-visual predictive check (KM-VPC) and sampling-importance resampling (SIR) methods were used to validate the final model. A total of 116 patients were included in the study, with a mean follow-up of 306 weeks. Weibull hazard function best fitted the data. The hazard of positive symptoms improvement decreased 4% for every one-year increase in age over the median of 41 years (adjusted hazard ratio (aHR), 0.96; 95% confidence intervals (95% CI), (0.93–0.98)). However, patients receiving a second atypical antipsychotic agent had four-folds higher hazard (aHR, 4.01; 95% CI, (1.97–7.17)). The hazard increased 2% (aHR, 1.02; 95% CI, (1.01–1.03)) for every 1 g increase in the clozapine six months cumulative dose over the median of 34 g. The developed model provides essential information on the hazard of positive symptoms improvement after the first clozapine dose administration, including modifiable predictors of high clinical importance.

There are established correlation between risk factors and the recurrence of ischemic stroke (IS), however does the hazard of recurrent IS change although without the influence of established risk factors? This study aimed to quantify the hazard of recurrent IS at different time points after the index IS. This was a population cohort study extracted data of 7697 patients with a history of first IS attack registered with National Neurology Registry of Malaysia. A repeated time to recurrent IS model was developed using NONMEM version 7.5. Three baseline hazard models were fitted into the data. The best model was selected using maximum likelihood estimation, clinical plausibility and visual predictive checks. Three hundred and thirty-three (4.32%) patients developed at least one recurrent IS within the maximum 7.37 years follow-up. In the absence of significant risk factors, the hazard of recurrent IS was predicted to be 0.71 within the first month after the index IS and reduced to 0.022 between the first to third months after the index attack. The hazard of IS recurrence accelerated with the presence of typical risk factors such as hyperlipidaemia (HR, 2.64 [2.10-3.33]), hypertension (HR, 1.97 [1.43-2.72], and ischemic heart disease (HR, 2.21 [1.69-2.87]). In conclusion, the absence of significant risk factors, predicted hazard of recurrent IS was prominent in the first month after the index IS and was non-zero even three months after the index IS or later. Optimal secondary preventive treatment should incorporate the ‘nature risk’ IS recurrence.

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Background Extra-pulmonary tuberculosis (EPTB) represents about 14% of all cases of tuberculosis (TB) in Malaysia. The aims of the study include evaluation of socio-demographic factors, clinical manifestations, co-morbidities among patients with Tuberculous Lymphadenitis and their treatment outcomes.Methods The retrospective study was conducted from 2006 to 2008. Data on socio-demographic along with histopathological results were collected. Signs and symptoms were also recorded from TB registers, treatment cards and TB medical personal files using standard data collection tool. Among multiple variables significant factors identified by univariate analysis, were included in multivariate logistic regression to estimate the odds ratios (ORs) with the 95% confidence intervals (CIs). The statistically significant p value was considered as < 0.05.Results There were 348 (57%) males and on the other hand 262 (43%) females which shows almost equal incidence rate of Lymphadenitis in both genders. Mean age was found as 34.3 ± 14.6 years were majorly reported with positive diagnosis. 196 (32.1%) Malay was found with Tuberculous lymphadenitis followed by Chinese population of 148 (24.3%). Geographically from 386 (63.3%) urban population were found positive for lymphadenitis and over 224 (36.7%) of rural region. treatment outcome was observed 444 (72.8%) with successful treatment. WHO states the types of treatment failures and accordingly 85 (13.9%) patients were continued with the therapy that can be due to non-compliance or relapse of Tb. Among unsuccessful outcomes 194 patients of age group 26 -35 years, 65 (33.5%) were reported and 38 (29.7%) patients out of 128 between 16 – 25 years. Blood results showed erythrocyte sedimentation rate greater than 10 in 280 (45.9%) patients. Therefore, among 280 there were 115 (41.1%) patients found to have unsuccessful treatment showing strong association with p-value of <0.001.Conclusion Finding signifies that effect of weight loss on poor treatment outcomes` and active screening measures for patients with comorbidities are therefore recommended in patients with Tb lymphadenitis along with improvements in the diagnosis and early management of co-morbidities complications. As young age group were found to have poor or unsuccessful treatment outcomes and required aggressive strategy together with educating patients can further increase the treatment success rate.