CYP2B6 and ABCB1 genotypes predict methadone plasma exposure among patients on maintenance therapy against opioid addictions in Tanzania.

AIMS: Methadone maintenance therapy (MMT) exhibits significant variability in pharmacokinetics and clinical response, partly due to genetic variations. However, data from sub-Saharan African populations are lacking. We examined plasma methadone variability and pharmacogenetic influences among opioid-addicted Tanzanian patients. METHODS: Patients attending MMT clinics (n = 119) in Tanzania were genotyped for common functional variants of the CYP3A4, CYP3A5, CYP2A6, CYP2B6, CYP2C19, CYP2D6, ABCB1, UGT2B7 and SLCO1B1 genotypes. Trough plasma concentrations of total methadone, S-methadone (S-MTD) and R-methadone (R-MTD), with their respective metabolites, 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP), were quantified using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The methadone-to-EDDP metabolic ratio (MMR) was used to categorize the phenotype. RESULTS: The proportions of MMR-predicted ultrarapid, extensive, intermediate and slow methadone metabolizer phenotypes were 2.5%, 58.2%, 23.7% and 15.6%, respectively. CYP2B6 genotype significantly correlated with S-methadone (P = .006), total methadone (P = .03), and dose-normalized methadone plasma concentrations (P = .001). Metabolic ratios of R-methadone (R-MTD/R-EDDP), S-methadone (S-MTD/S-EDDP), and total methadone (MMR) were significantly higher among patients homozygous for defective variants (*6 or *18) than heterozygous or CYP2B6*1/*1 genotypes (P < .001). The metabolic ratio for S-MTD and total methadone was significantly higher among ABCB1c.3435T/T than in the C/C genotype. No significant effect of CYP2D6, CYP2C19, CYP3A4, CYP3A5, CYP2A6, UGT2B7 and SLCO1B1 genotypes on S-methadone, R-methadone, or total methadone was observed. CONCLUSIONS: Approximately one in six opioid-addicted Tanzanian patients are methadone slow metabolizers, influenced by genetic factors. Both the CYP2B6 and ABCB1 genotypes are strong predictors of methadone metabolic capacity and plasma exposure. Further investigation is needed to determine their predictive value for methadone treatment outcomes and to develop genotype-based dosing algorithms for safe and effective therapy.

Sub- and supratherapeutic efavirenz plasma concentrations with risk for HIV therapy failure are mainly genetically explained in Ugandan children: The prospective GENEFA cohort study.

AIMS: Interindividual variations in efavirenz (EFV) plasma concentrations are extensive, but paediatric data on its consequences for viral control are scarce. The aim of this study was to explore the role of genetic variation in achieving therapeutic efavirenz plasma concentrations in a cohort of Ugandan children and the linkage between genetic CYP2B6 variants, EFV plasma variability, viral resistance and viral outcome. METHODS: Ninety-nine treatment-naïve children, aged 3-12 years and living with HIV, were followed for 24 weeks after ART initiation assessing mid-dose efavirenz plasma concentrations, HIV RNA, HIV drug resistance and adherence. Polymorphisms in genes coding for drug-metabolizing enzymes were genotyped. Efavirenz concentrations were determined by liquid chromatography coupled with high-resolution tandem mass spectrometry. Metabolizer phenotype was predicted from composite genotypes of CYP2B6 (c.516G>T and c.983 T>C). A mixed effects restricted maximum likelihood regression model was used to identify important factors for efavirenz exposure. RESULTS: Efavirenz plasma concentrations were below the therapeutic interval (1000-4000 mg/mL) in 12-17% and above in 21-24% of measurements. Eight children had persisting subtherapeutic concentrations, five of which failed virologically and three acquired at least one new resistant mutation. Multivariate modelling explained 70% of interindividual variation in plasma concentration, with treatment duration, adherence, CYP2B6c.136A>G, and metabolizer phenotype as independent predictors of EFV concentration. In univariate analysis, metabolizer phenotype explained 50% of interindividual variation. CONCLUSIONS: Metabolizer phenotype explained 50% of interindividual variation in efavirenz plasma concentration. Autoinduction was not confirmed and >33% of the concentrations were outside the therapeutic interval. Subtherapeutic concentrations worsened virological resistance and outcomes. Genotype-based dosing may help avert both sub- and supratherapeutic efavirenz plasma concentrations in Ugandan children.

Pharmacokinetics of methylphenidate and ritalinic acid in plasma correlations with exhaled breath and oral fluid in healthy volunteers.

PURPOSE: The primary aim of this study was to explore the potential of alternative sampling matrices for methylphenidate by assessing the correlations between dl-threo-methylphenidate and dl-threo-ritalinic acid concentrations in exhaled breath and oral fluid with those in plasma, in repeated samples collected after a single oral dose of methylphenidate. The secondary aim was to study the enantioselective pharmacokinetics of methylphenidate in plasma, with a focus on interindividual variability in the metabolism of methylphenidate to ritalinic acid. METHODS: Twelve healthy volunteers received a single oral dose of dl-threo-methylphenidate (Ritalin® capsules, 20 mg). Venous blood samples were collected for 24 h, and plasma analyzed for threo-enantiomers of methylphenidate and ritalinic acid with LC-MS/MS. Repeated sampling of exhaled breath, using a particle filter device, and of non-stimulated oral fluid, using a felt pad device, was also performed. Exhaled breath and oral fluid were analyzed with a non-enantioselective LC-MS/MS method for dl-threo-methylphenidate and dl-threo-ritalinic acid. RESULTS: In all subjects, d-threo-methylphenidate was detectable in plasma for at least 15 h after the dose with a biphasic profile. l-threo-Methylphenidate was measurable in only five subjects and in most cases in low concentrations. However, one female subject displayed a biphasic concentration-time profile for l-threo-methylphenidate. This subject also had the highest d-threo-methylphenidate AUC (191 ng*h/mL versus 32-119 ng*h/mL in the other subjects). d-threo-Ritalinic acid concentrations were on average 25-fold higher (range 6-126) than the corresponding d-threo-methylphenidate concentrations. Single-time point plasma concentration ratios between d-threo-ritalinic acid and d-threo-methylphenidate 1.5-12 h after dose correlated highly (r = 0.88-0.98) with the d-threo-ritalinic acid AUC/d-threo-methylphenidate AUC ratio. In eleven subjects, dl-threo-methylphenidate in oral fluid mirrored the biphasic profile of methylphenidate (sum of d- and l-threo-enantiomers) in plasma, but the concentrations in oral fluid were on average 1.8 times higher than in plasma. dl-threo-Methylphenidate was detected in exhaled breath in all subjects, but there was no consistent concentration-time pattern. CONCLUSIONS: In some subjects, the pharmacologically less active l-threo-enantiomer may contribute to the total plasma methylphenidate concentrations. Monitoring methylphenidate concentrations without enantiomeric determination carries the risk of missing such subjects, which might affect how the plasma concentrations of methylphenidate are interpreted and used for clinical decision making. The use of exhaled breath and oral fluid to assess medication adherence to MPH in patients with ADHD warrants further studies.

Male Anabolic Androgenic Steroid Users with Personality Disorders Report More Aggressive Feelings, Suicidal Thoughts, and Criminality.

Background and objectives: Anabolic androgenic steroids (AAS) are mainly used for aesthetic and performance-enhancing reasons. Their use is a growing public health problem and concern for society because of their adverse effects. The primary aim of this study was to identify psychiatric and personality disorders and to measure anxiety and depression in AAS users. Materials and Methods: Fifty-six males who actively contacted the Anti-Doping Hot-Line and wished to stop using AAS were included. Structured Clinical Interviews Diagnosis-I and -II were used to diagnose psychiatric and personality disorders. The Brief Scale for Anxiety and Montgomery Asberg Depression Rating Scale (subscales from the Comprehensive Psychopathological Rating Scale) were used to measure changes in anxiety and depression. Structured Clinical Interviews Diagnosis-I and -II were performed at one time point. Anxiety and depression were measured at inclusion and after six months. Urine samples were collected for an analysis of AAS and drugs of abuse. Results: All participants reported some adverse effects that they associated with AAS use. In total, 56% and 52% of the cohort fulfilled the criteria for Structured Clinical Interviews Diagnosis-I and -II diagnoses, respectively. A significantly increased risk of reporting aggressive feelings/behaviors (Odds Ratio (OR) = 4.9; Confidence Interval (CI) 0.99-25, p = 0.04), suicidal thoughts/attempts (OR = 4.6, CI 95; 0.99-21, p = 0.04) and criminality (OR = 6.5, CI 1-39, p = 0.03) was found among individuals with AAS use fulfilling the criteria for personality disorders compared with those without such AAS use. The Brief Scale for Anxiety score decreased from the median of 15 at inclusion to 10 at the follow-up visit six months later (p = 0.01, n = 19). Conclusions: Our findings indicate that among individuals with AAS use, those with a personality disorder report more aggressive behaviors, suicidal thoughts/suicidal attempts, and criminality than those without a personality disorder.

Methylphenidate effects on processing speed in a clinical sample of adults with ADHD and substance use disorder: a pilot study.

BACKGROUND: Substance use disorders (SUDs) are common comorbidities of Attention Deficit Hyperactivity Disorder (ADHD). The most commonly prescribed medication for ADHD is methylphenidate. The clinical response to methylphenidate may be monitored against DSM-5 symptomatology, rating scales or interviews. AIMS: To evaluate the use of perceptual and cognitive processing speed measures to monitor methylphenidate effects in adults with ADHD and SUD. METHODS: A Quick Test of Cognitive Speed (AQT) monitored perceptual and cognitive processing speed in 28 adults with ADHD and SUD on treatment with methylphenidate before and after the morning dose. RESULTS: Twenty-six patients responded on AQT after the morning dose of methylphenidate. One-way ANOVA indicated significant treatment effects for color, form, and color-form combination naming, but not for shift cost values. Before the morning dose of methylphenidate, 92% were identified by cutoff time criteria for longer-than-normal processing times. After the morning dose of methylphenidate, 65% obtained color and form measures in the normal range for age peers. Only 35% obtained color-form processing measures in the normal range. Inter-individual response variability before medication intake was considerably larger than previously reported in studies of adults with ADHD only. CONCLUSION: Proportionally, fewer adults with ADHD and SUD exhibited normalization of processing speed than previously observed for adults with ADHD without SUD. A potential clinical implication of the present study is that the AQT test may be used as a tool for dose-adjustment of central stimulants in the treatment of adults with ADHD and SUD.

Increased levels of IL-6 in the cerebrospinal fluid of patients with chronic schizophrenia--significance for activation of the kynurenine pathway.

BACKGROUND: Accumulating evidence indicates that schizophrenia is associated with brain immune activation. While a number of reports suggest increased cytokine levels in patients with schizophrenia, many of these studies have been limited by their focus on peripheral cytokines or confounded by various antipsychotic treatments. Here, well-characterized patients with schizophrenia, all receiving olanzapine treatment, and healthy volunteers were analyzed with regard to cerebrospinal fluid (CSF) levels of cytokines. We correlated the CSF cytokine levels to previously analyzed metabolites of the kynurenine (KYN) pathway. METHODS: We analyzed the CSF from patients and controls using electrochemiluminescence detection with regard to cytokines. Cell culture media from human cortical astrocytes were analyzed for KYN and kynurenic acid (KYNA) using high-pressure liquid chromatography or liquid chromatography/mass spectrometry. RESULTS: We included 23 patients and 37 controls in our study. Patients with schizophrenia had increased CSF levels of interleukin (IL)-6 compared with healthy volunteers. In patients, we also observed a positive correlation between IL-6 and the tryptophan:KYNA ratio, indicating that IL-6 activates the KYN pathway. In line with this, application of IL-6 to cultured human astrocytes increased cell medium concentration of KYNA. LIMITATIONS: The CSF samples had been frozen and thawed twice before analysis of cytokines. Median age differed between patients and controls. When appropriate, all present analyses were adjusted for age. CONCLUSION: We have shown that IL-6, KYN and KYNA are elevated in patients with chronic schizophrenia, strengthening the idea of brain immune activation in patients with this disease. Our concurrent cell culture and clinical findings suggest that IL-6 induces the KYN pathway, leading to increased production of the N-methyl-D-aspartate receptor antagonist KYNA in patients with schizophrenia.

Statin-induced muscle toxicity and susceptibility to malignant hyperthermia and other muscle diseases: a population-based case-control study including 1st and 2nd degree relatives.

PURPOSE: Case reports have suggested an association between susceptibility to malignant hyperthermia (MH) and other muscle diseases in subjects with statin-induced muscle toxicity. The aim of the study was to further scrutinize this association in a population-based case-control study including 1st and 2nd degree relatives. METHODS: Spontaneously reported cases with muscle disorders associated with statin therapy until September 2006 were identified in the Swedish Adverse Drug Reaction Registry at the Medical Products Agency. For each case, ten population-based controls, matched on year of birth and gender, were randomly selected from the National Registry of Swedish Citizens. First and 2nd degree relatives to cases and controls were identified in the Swedish Multi-Generation Registry. ICD codes that could be associated with susceptibility to MH or other muscle diseases were chosen, and subjects were followed until December 2007 with regard to occurrence of selected ICD codes in the Swedish Registries for Cause of Death and Hospital Discharge Diagnoses, respectively. RESULTS: The chosen ICD codes were significantly overrepresented in case families compared with control families (RR 1.56; 95 % CI 1.15-2.10). The strongest associations were identified for a diagnosis of drug-induced or specified or unspecified myopathy (RR 52; 95 % CI 22-123) or a diagnosis of unspecified hyperthermia in combination with drug-induced or specified or unspecified myopathy (RR 30; 95 % CI 6-148). In contrast, a diagnosis of unspecified hyperthermia in the absence of drug-induced or specified or unspecified myopathy was significantly underrepresented among case families (RR 0.42; 95 % CI 0.23-0.76). CONCLUSIONS: In a case-control study including 1st and 2nd degree relatives, statin-induced muscle toxicity was significantly associated with a diagnosis of drug-induced or specified or unspecified myopathy and with a diagnosis of unspecified hyperthermia in combination with a diagnosis of drug-induced or specified or unspecified myopathy.

CYP2C19*17 affects R-warfarin plasma clearance and warfarin INR/dose ratio in patients on stable warfarin maintenance therapy.

PURPOSE: We aimed to assess the influence of CYP2C19*17 on R-warfarin clearance as well as the effect of CYP2C19, CYP2C8, CYP2C9, and VKORC1 polymorphisms together with non-genetic factors on warfarin international normalized ratio (INR)/daily dose. METHODS: One hundred fifty Caucasian Italian outpatients with data on steady-state plasma concentrations of S- and R-warfarin were genotyped for CYP2C19 (*2, *3, *4, *17), CYP2C9 (*2, *3), CYP2C8*3, and VKORC1*2. The statistical analysis was performed on the effect of genotypes/haplotypes, age, sex, and body weight on the clearance of warfarin enantiomers and dose-normalized INR. RESULTS: R-warfarin clearance was 32% higher in carriers of CYP2C19*17 than in carriers of CYP2C19*2 (mean 2.5 mL/min, 95% confidence interval (CI) 2.3-2.8 vs. 1.9 mL/min, 95% CI 1.7-2.2; P post hoc = 0.01). Patients with CYP2C19*1/*1 genotype had an intermediate clearance (mean 2.1 mL/min, 95% CI 1.8-2.4). The genotypes of VKORC1, CYP2C9, and CYP2C19, together with non-genetic factors (age, sex, and body weight) explained 52% of the variability in warfarin INR/daily dose, of which CYP2C19 genotypes accounted for 7%. CONCLUSIONS: This is the first study to include the gain-of-function CYP2C19*17 allele when assessing the impact of CYP2C19 polymorphisms on the clearance of warfarin enantiomers. CYP2C19 genotypes influenced the clearance of R-warfarin and contributed significantly to the variability in INR/daily dose, indirectly indicating a clinical relevance of R-warfarin.

No influence of CYP3A43 rs472660G> A on steady-state serum olanzapine concentrations in white psychiatric patients.

The potential involvement of CYP3A43 in systemic olanzapine (OLA) metabolism has been suggested by one reported association between the intronic polymorphism CYP3A43 rs472660G>A and OLA clearance in 235 White and African-American patients. Trough plasma OLA concentrations in AA carriers were predicted on average 48% lower than in GG carriers. In the current study, we evaluated this finding by genotyping 374 White psychiatric patients on long-term OLA treatment. No significant difference in dose-adjusted trough serum OLA concentrations was observed between the seven AA carriers identified and the other two genotypes, without (P=0.6) or with (P=0.23) adjustment for additional covariates previously known to influence systemic OLA exposure. Because of the low prevalence of the rs472660 AA genotype in White populations (2%), larger study cohorts are needed for future association confirmation. Overall, CYP3A43 rs472660 is not likely to be a major contributor towards variability in systemic OLA exposure among White patients.

Lived experiences of closeness to a person using Anabolic androgenic steroids a next of kin perspective.

PURPOSE: Anabolic androgenic steroids (AAS) are used for their aesthetic and performance-enhancing effects and are associated with physical and psychological side effects. Behavioural changes/side effects as mood swings, aggressiveness, depression, potency problems, anxiety, and emotional coldness have been reported by next of kin to people using AAS. METHODS: This phenomenological study is based on the reflective lifeworld research approach. Interviews were conducted with twelve next of kin about their experiences of living close to persons using AAS. RESULTS: Next of kin to persons using AAS are particularly vulnerable because they experience little opportunity to influence their situation. Their given and safe context is lost, and their lives are circumscribed by feelings of insecurity, fear, powerlessness, and grief. Feelings of loneliness develop when their problems are not noticed by others and support is lacking from family and society. CONCLUSIONS: Our research adds important knowledge on how the use of AAS affects next of kin. Understanding is required to approach the lifeworld of next of kin with flexibility and empathy in their difficulties and vulnerability. Healthcare professionals and other concerned professions need to be aware of next of kin existential needs to be able to meet and support them in their life situation.

CYP2C19 and CYP2J2 genotypes predict praziquantel plasma exposure among Ethiopian school-aged children.

Metabolism of praziquantel (PZQ), a racemic mixture and the only drug approved to treat S. mansoni infection, is mediated by genetically polymorphic enzymes. Periodic school-based mass drug administration (MDA) with PZQ is the core intervention to control schistosomiasis. However data on the impact of pharmacogenetic variation, nutrition, and infection status on plasma PZQ exposure is scarce. We investigated genetic and non-genetic factors influencing PZQ plasma concentration and its metabolic ratios (trans-4-OH-PZQ/PZQ and cis-4-OH-PZQ/PZQ). Four hundred forty-six school children aged 7-15 years from four primary schools in southern Ethiopia who received albendazole and PZQ preventive chemotherapy through MDA campaign were enrolled. Genotyping for common functional variants of CYP3A4 (*1B), CYP3A5 (*3, *6), CYP2C19 (*2, *3, *17), CYP2C9 (*2, *3), and CYP2J2*7 was performed. Plasma concentrations of PZQ, trans-4-OH-PZQ, and cis-4-OH-PZQ were quantified using UPLCMS/MS. Carriers of CYP2C19 defective variant alleles (*2 and *3) had significantly higher mean PZQ plasma concentration than CYP2C19*1/*1 or *17 carriers (p = 0.005). CYP2C19*1/*1 and CYP2C19*17 carriers had higher trans-4-OH-PZQ/PZQ and cis-4-OH-PZQ/PZQ metabolic ratios compared with CYP2C19*2 or *3 carriers (p < 0.001). CYP2J2*7 carriers had lower mean PZQ plasma concentration (p = 0.05) and higher trans-4-OH-PZQ/PZQ and cis-4-OH-PZQ/PZQ metabolic ratios. Male participants had significantly higher PZQ concentration (p = 0.006) and lower metabolic ratios (p = 0.001) than females. There was no significant effect of stunting, wasting, S. mansoni or soil-transmitted helminth infections, CYP3A4, CYP3A5, or CYP2C9 genotypes on plasma PZQ or its metabolic ratios. In conclusion, sex, CYP2C19 and CYP2J2 genotypes significantly predict PZQ plasma exposure among Ethiopian children. The impact of CYP2C19 and CYP2J2 genotypes on praziquantel treatment outcomes requires further investigation.

Influence of CYP1A1/CYP1A2 and AHR polymorphisms on systemic olanzapine exposure.

OBJECTIVE: Metabolism of the atypical antipsychotic olanzapine (OLA) is partially catalyzed by cytochrome P450 (CYP) 1A2, a target of aryl hydrocarbon receptor (AHR)-mediated induction. We investigated the influence of four cis-acting polymorphisms (rs2470893C>T and rs2472297C>T between CYP1A1 and CYP1A2 loci, and rs762551C>A and rs2472304A>G within CYP1A2) as well as one trans-acting polymorphism upstream of the AHR locus (rs4410790C>T) on interindividual variation in systemic OLA exposure. METHODS: A cohort of 342 Caucasian psychiatric patients on long-term OLA treatment was genotyped using Illumina GoldenGate assays. The influence of haplotype and genotype was evaluated in terms of dose-adjusted steady-state serum concentrations (C/Ds) of OLA and the 4'-desmethyl OLA (DMO) to OLA ratio, a marker for CYP1A2-mediated metabolism of OLA. RESULTS: The CYP1A haplotype [rs2470893 (T)-rs2472297 (T)-rs762551 (A)] was associated with an increased DMO/OLA ratio and decreased C/Ds of OLA. This haplotype could not be tagged by rs762551 (A) but was tagged by rs2472297C>T, a single nucleotide polymorphism further identified as a significant covariate of the DMO/OLA ratio (P=0.0001) and OLA C/D (P=0.01). AHR rs4410790C>T influenced only the DMO/OLA ratio (P=0.02). Among nonsmokers, patients carrying rs2472297 (T) and homozygous for rs4410790 (C) [n=26; mean=0.22, 95% confidence interval (CI) 0.19-0.26] showed a 1.7-fold higher mean DMO/OLA ratio compared with those carrying rs4410790 (T) and homozygous for rs2472297 (C) (n=50; mean=0.13, 95% CI 0.12-0.16, P=0.0001), together with a nonsignificant decrease in the mean OLA C/D. CONCLUSION: The reported influence of CYP1A2*1F (also known as CYP1A2-163A, rs762551C>A) on systemic OLA exposure could not be verified. CYP1A1/CYP1A2 rs2472297C>T and AHR rs4410790C>T are potentially useful genetic markers associated with variability in CYP1A2-mediated metabolism, but are of minor quantitative importance for systemic OLA exposure.

Therapeutic drug monitoring for tomorrow.

Therapeutic drug monitoring (TDM) represents an early approach to personalised medicine. It helps the clinician to individualise drug treatment and guide dosage to reach systemic drug concentrations associated with therapeutic efficacy and/or to reduce the risk of concentration-dependent adverse effects. Well into the fifth decade of TDM as a service to healthcare, this concept is still expanding, and new areas for clinical implementation continue to emerge. The aim of this overview is to discuss promising new therapeutic areas in future TDM services, how to improve the clinical interpretation of single drug measurements and how recent technology development opens the doors to research and new applications.

Pharmacological Risk Assessment Among Older Patients with Polypharmacy Using the Clinical Decision Support System Janusmed Risk Profile: A Cross-Sectional Register Study.

BACKGROUND: Polypharmacy in older people is steadily increasing and a combination of many medicines may result in adverse effects, especially if the medicines interact pharmacodynamically. Examples are additive or synergistic effects increasing the risk of falls, haemorrhage, serotonin syndrome and torsade de pointes. The clinical decision support system Janusmed Risk Profile has been developed to find such risks based on a patients' medication list. OBJECTIVES: The main aim of this retrospective register-based study was to study what pharmacodynamic risks older patients (aged 65 years or older) on polypharmacy (defined as using five or more medicines) are exposed to. Second, we studied if the introduction of the Janusmed Risk Profile in the main electronic health record system in Region Stockholm influenced the proportion of patients prescribed combinations that increase the risk for the nine adverse-effect categories defined (anticholinergic effects, haemorrhage, constipation, orthostatism, QT prolongation, renal toxicity, sedation, seizures and serotonin syndrome). METHODS: Data on all prescription medicines to individuals aged 65 years or older, and with at least five concomitant medicines were retrieved and analysed for the risk categories in the Janusmed Risk Profile. The proportions of patients with a high/moderate risk during a 4-month period before (period 1) and after (period 2) the introduction were compared. RESULTS: A total of 127,719 patients in period 1 (November 2016-February 2017), and 131,458 patients in period 2 (November 2017-February 2018) were included in the study. The proportion of patients with a high or moderate risk for each of the nine properties (anticholinergic effects, haemorrhage, constipation, orthostatism, QT prolongation, renal toxicity, sedation, seizures and serotonergic effects) were 10.9, 34.7, 32.8, 33.6, 17.2, 0.7, 15.4, 0.5 and 2.4%, respectively, in period 1 and 10.4, 35.5, 32.8, 33.3, 10.8, 0.71, 14.9, 0.5 and 2.3% in period 2. The changes for sedation and QT prolongation were statistically significant, with the most pronounced decrease for QT prolongation from 17.2 to 10.8% (p < 0.001). When analysing patients at a high risk, the decrease was significant for haemorrhage, orthostatism, QT prolongation and sedation. CONCLUSIONS: Older people are exposed to combinations of medications that increase the risk for potentially severe adverse effects. Prescribers seem to respond especially to warnings for QT prolongation, presented in the Janusmed Risk Profile implemented in the electronic health record system.

Plasma concentrations of methylphenidate enantiomers in adults with ADHD and substance use disorder, with focus on high doses and relationship to carboxylesterase activity.

Scarce data are available on methylphenidate (MPH) plasma concentrations reached after doses higher than 180 mg. The interindividual and intraindividual variability in the exposure of MPH and ritalinic acid (RA) enantiomers was examined in 28 patients with ADHD and substance use disorders, with MPH daily doses between 30 and 600 mg (median 160 mg). MPH and RA plasma concentrations were analysed with an enantioselective LC-MS/MS method. d-MPH plasma concentration/dose varied 25-fold between subjects but was reasonably stable within an individual. Twelve subjects had quantifiable l-MPH plasma concentrations, which accounted for up to 48% of the total MPH plasma concentration. The less active l-MPH enantiomer could, in individuals with low carboxylesterase 1 (CES1) activity, contribute significantly to the total MPH plasma drug concentration and hamper the estimation of the exposure to the more active d-MPH enantiomer. However, the high correlation between the total (d + l) RA/MPH metabolic ratio and the d-RA/d-MPH metabolic ratio (rs  = 0.94) indicates that the ratio based on non-enantioselective analysis could be used as a marker of CES1 activity. Whether this holds true for subjects with aberrant metabolism due to genetic variants or during concomitant treatment with inhibitors or inducers of the enzyme remains to be studied.

High correlation between serum and cerebrospinal fluid olanzapine concentrations in patients with schizophrenia or schizoaffective disorder medicating with oral olanzapine as the only antipsychotic drug.

The primary aim of the present study was to investigate the relationship between steady state serum and cerebrospinal fluid (CSF) concentrations of olanzapine (OLA) and its metabolite 4'-N-desmethylolanzapine (DMO) in patients with schizophrenia or schizoaffective disorder treated with oral OLA as the only antipsychotic drug. The influence of smoking, gender, age, as well as polymorphisms in cytochrome P450 CYP2D6, CYP1A2, and ABCB1 genes on the serum and CSF drug levels was also analyzed. Thirty-seven white outpatients (10 smokers and 27 nonsmokers) were included. From 29 of them, CSF was collected successfully. A strong correlation (Spearman rank correlation [rs] = 0.93; P < 0.05) was found between serum and CSF concentrations of OLA and a somewhat weaker correlation (rs = 0.5; P < 0.05) between those of DMO. The CSF concentrations of OLA and DMO were on average 12% and 16% of those in serum. Extensive metabolizers of CYP2D6 had higher (P < 0.05) daily doses than poor metabolizers when the influence of smoking was taken into account. Smokers had lower (P < 0.01) concentration-to-dose ratios of OLA in serum (mean, 2.23 ng/mL per mg vs 3.32 ng/mL per mg) and CSF (0.27 ng/mL per mg vs 0.41 ng/mL per mg) than nonsmokers. The concentration-to-dose ratio for serum DMO decreased with increasing age (rs = -0.41; P < 0.05). Carriers of ABCB1 1236T/2677T/3435T haplotype had higher serum (mean, 37.7 ng/mL vs 22.5 ng/mL; P = 0.035) and CSF (4.7 ng/mL vs 2.6 ng/mL; P = 0.018) OLA concentrations than patients without this haplotype. The present study shows a strong correlation between serum and CSF concentrations of OLA, indicating that concentrations of OLA in serum reflect those in CSF.

Do CYP3A and ABCB1 genotypes influence the plasma concentration and clinical outcome of donepezil treatment?

PURPOSE: The aim of our study was to evaluate the impact of CYP3A4, CYP3A5, and ABCB1 polymorphisms on donepezil disposition and clinical outcome. METHODS: Fifty-four Italian patients diagnosed with probable mild to moderate Alzheimer's disease, treated with donepezil (37 patients 5 mg/day, 17 patients 10 mg/day) were genotyped for CYP3A4 (*1B, *3, and *4), CYP3A5 (*2, *3, and *6) and ABCB1 (3435C>T, 2677G>T/A, and 1236C>T) polymorphisms. All patients were evaluated for the degree of cognitive impairment with Mini Mental State Examination (MMSE) screening test at baseline (before treatment) and after at least 3 months of donepezil treatment at stable dose, when the drug plasma levels were measured. RESULTS: Three patients carried one detrimental CYP3A4 allelic variant, and 12 carried one functional CYP3A5*1 allele. No statistically significant association was found between CYP3A4 or CYP3A5 genotypes and plasma donepezil concentrations, or between genotypes and clinical response (as measured by change in MMSE score). Nine ABCB1 haplotypes were observed, the most common being 1236C/2677G/3435C (46%) and 1236T/2677T/3435T (41%). Patients homozygous for the T/T/T haplotype had slightly though not significantly lower plasma donepezil concentration-to-dose ratios than those carrying other genotypes [median (95% CI) 0.18 (0.13-0.45) vs. 0.31 (0.30-0.44) mg/l/mg/kg, respectively]. These patients also showed a slightly better clinical response (as measured by change in MMSE score) than the other genotype groups [median (95% CI) 0 (-1.3 to 3.3) vs. -1.0 (-2.1 to 0.0), respectively]. CONCLUSIONS: Our data suggest that the CYP3A4 and CYP3A5 polymorphisms are unlikely to influence donepezil metabolism and/or clinical outcome. On the other hand, the ABCB1 polymorphisms may play a role in donepezil disposition and clinical outcome.

Mild hypoglycaemic attacks induced by sulphonylureas related to CYP2C9, CYP2C19 and CYP2C8 polymorphisms in routine clinical setting.

AIM: To evaluate the impact of polymorphisms in the cytochrome P450 (CYP) 2C9, 2C19 and 2C8 genes on the risk of mild hypoglycaemic attacks in patients treated with sulphonylureas. METHODS: One hundred and eight type 2 diabetic patients (50 men, 58 women), treated with oral antidiabetics, including at least one from the sulphonylurea group (glimepiride n = 50, gliclazide n = 46, or glipizide n = 12) for 3 months or longer, were included in the study. Symptoms of hypoglycaemia (sweating, tremor, anxiety and palpitations) during a 3 month period were recorded and confirmed by home glucose measurements. Gender, age, body mass index, creatinine clearance, HbA1c, oral antidiabetic dose and concomitant medication were assessed together with functional CYP2C9, CYP2C19 and CYP2C8 polymorphisms, analysed by real-time PCR methods. RESULTS: Fifteen patients (eight men, seven women) reported hypoglycaemia symptoms which were validated by their home glucose measurements (< 70 mg/dl). Heterozygosity and homozygosity for CYP2C9 variant alleles (*2 or *3) tended to be more frequent among patients who reported hypoglycaemic attacks (60 and 7%) than those who did not (39 and 3%). Similarly, the CYP2C8*1/*3 genotype tended to be more frequent in patients with (47%) than without (27%) hypoglycaemia, while no such trend was observed for CYP2C19 variants. However, only in the gliclazide group a significant association between CYP2C9 genotype and hypoglycaemic attacks was observed (P = 0.035). None of the other covariates showed any significant association with the risk of hypoglycaemic attacks. CONCLUSIONS: CYP2C9 polymorphisms leading to decreased enzyme activity show a modest impact on the risk of mild hypoglycaemia attacks during oral antidiabetic treatment, with a significant association in patients treated with gliclazide.

A Summary of Online Enquiries Submitted to Anti-doping Hotline 2005-2018.

Anabolic Androgenic Steroid (AAS) abuse in the society is considered a health problem and has been associated with cardiovascular toxicity, endocrine disruption, as well as psychiatric symptoms such as aggression and cognitive dysfunction. Men and women abusing AAS, as well as persons in close relationship to AAS abusers, may encounter concerns. Subsequently, the Anti-Doping Hotline was formed 1993 to answers questions about doping in the society. Here we have reviewed 7,123 enquiries posted on the Anti-Doping Hotline website between 2005 and 2018 to see what type of questions were raised. Most questions (n = 2,924) involved AAS, 60% from abusers themselves, and 17% from a person close to an AAS abusers. Only 2.3% of the questions concerned AAS abusing women. Of the AAS specific questions most were from persons who sought personal advice regarding risks and side effects. Notably, the AAS abusers themselves were concerned about somatic side effects (e.g., gynecomastia) and problems related to the AAS injection. The persons in close relationship to an AAS abusers on the other hand, expressed concerns about psychiatric changes including mood swings and aggressivity. In addition to AAS, 26 and 13% of the questions involved dietary supplements and other doping substances, respectively. A gradual decrease of questions regarding ephedrine was noted, whereas the numbers of SARMs related questions increased during this time. Our results show that there is a continuous need to provide medical, nursing, and social support and counseling to AAS abusers and their next of kin.