The phenotype of adverse drug effects: Do emergency visits due to adverse drug reactions look different in older people? Results from the ADRED study.

AIMS: Older patients in particular suffer from adverse drug reactions (ADR) when presenting in the emergency department. We aimed to characterise the phenotype of those ADRs, to be able to recognise an ADR in older patients. METHODS: Cases of ADRs in emergency departments collected within the multicentre prospective observational study (ADRED) were analysed (n = 2215). We analysed ADR-associated diagnoses, symptoms and their risk profiles. We present frequencies and odds ratios (OR) with 95% confidence intervals for adults (18-64 years) compared to older adults (≥65 years; young-old 65-79, old-old ≥80 years) and regression coefficients (B) for each year of age. RESULTS: Most prominent differences were seen for drug-associated confusion, dehydration, and bradycardia (OR 6.70 [1.59-28.27], B .054; OR 6.02 [2.41-15.03], B .081, and 4.82 [2.21-10.54], B .040), more likely seen in older adults. Bleedings were reported in all age groups, but gastrointestinal bleedings occurred with more than doubled chance in older adults (OR 2.46 [1.77-3.41], B .030), likewise did other bleedings such as haemorrhage from respiratory passages (OR 2.89 [1.37-6.11], B.036). Falls were more likely in older adults (OR 2.84 [1.77-4.53], B .030), while dizziness was frequent in both age groups. CONCLUSION: Our data point to differences in symptoms of ADRs between adults and older individuals, with dangerous drug-associated phenomena in the older adult such as bleedings or falls. Physicians should consider drug-associated origins of symptoms in older adults with an increased risk for serious health problems.

Personalising drug safety-results from the multi-centre prospective observational study on Adverse Drug Reactions in Emergency Departments (ADRED).

PURPOSE: Adverse drug reactions (ADR) account for 5 to 7% of emergency department (ED) consultations. We aimed to assess medication risk profiles for ADRs leading to ED visits. METHODS: We analysed medication intake and patient demographics in a prospective multi-centre observational study collecting ADR cases in four large EDs in Germany. Odds ratios (OR) were calculated to relate drug classes taken to those suspicious for an ADR after a causality assessment. RESULTS: A total of 2215 cases of ED visits due to ADRs were collected. The median age of the cohort was 73 years; in median, six co-morbidities and an intake of seven drugs were documented. Antineoplastic/immunomodulating agents had the highest OR for being suspected for an ADR (OR 20.45, 95% CI 14.54-28.77), followed by antithrombotics (OR 2.94, 95% CI 2.49-3.47), antibiotics (OR 2.65, 95% CI 1.78-3.95), systemic glucocorticoids (OR 2.43, 95% CI 1.54-3.82) and drugs affecting the central nervous system (CNS), such as antipsychotics (OR 2.36, 95% CI 1.46-3.81), antidepressants (OR 2.10, 95% CI 1.57-2.83), antiparkinsonian medication (OR 2.11, 95% CI 1.15-3.84), opioids (OR 1.79, 95% CI 1.26-2.54) and non-opioid analgesics (OR 1.32, 95% CI 1.01-1.72). CONCLUSIONS: Patients experiencing ADRs leading to ED visits are commonly old, multi-morbid and multi-medicated. CNS drugs may be more relevant than prior expected. With calculating ORs, we could replicate involvement of antineoplastic agents, antithrombotics, antibiotics, systemic glucocorticoids and non-opioid analgesics as frequently suspected for ADRs in EDs. TRIAL REGISTRATION: DRKS-ID: DRKS00008979.

Prevalence of Psychotropic Drugs in Cases of Severe Adverse Drug Reactions Leading to Unplanned Emergency Visits in General Hospitals.

INTRODUCTION: The prevalence of psychotropic drug use in our society is increasing especially in older adults, thereby provoking severe adverse drug reactions (ADR). To identify specific patient risk profiles associated with psychotropic drug use in the situation of polymedication. METHODS: Cases of ADRs in general emergency departments (ED) collected within the multi-center prospective observational study (ADRED) were analyzed (n=2215). We compared cases with use of psychotropic drugs and without concerning their clinical presentation at the ED. RESULTS: A third of patients (n=731, 33%) presenting to the ED with an ADR took at least 1 psychotropic drug. Patients with psychotropic drug use tended to be older, more often female, and took a higher number of drugs (all p<0.001). The frequency of falls was almost 3 times higher than compared to the non-psychotropic drug group (10.5 vs. 3.9%, p<0.001), and similar syncope was also more often seen in the psychotropic drug users (8.8 vs. 5.5%, p=0.004). The use of psychotropic drugs increased the risk for falls by a factor of 2.82 (OR, 95% CI (1.90-4.18)), when adjusting for gender, age, numbers of pre-existing diseases, and drugs, respectively. DISCUSSION: The association of psychotropic drug use with fall and syncope in combination with polymedication and older age leads to the suspicion that psychotropic drugs might be potentially harmful in specific risk populations such as older adults. It may lead us to thoroughly weigh the benefit against risk in a patient-oriented way, leading to an integrative personalized therapy approach.

Fall-Associated Drugs in Community-Dwelling Older Adults: Results from the ActiFE Ulm Study.

OBJECTIVES: Many studies describing an association of drugs with falls focus mostly on drugs acting in the central nervous system. We aim to analyze the association of all drugs taken with falls in older adults. DESIGN: Prospective population-based study (ActiFE study). SETTING AND PARTICIPANTS: A total of 1377 community-dwelling older adults with complete recording of falls and baseline information on drug intake. METHODS: Negative binomial regression was used to analyze the association of 34 drug classes with a 12-month incidence rate ratio (IRR) of falls adjusting for age, sex, comorbidities, gait speed, balance, chair rise, kidney function, liver disease, and smoking. RESULTS: Participants took a median 3 drugs (interquartile range 1, 5), with 34.5% (n = 469) having ≥5 drugs. The median IRR for a fall per person-year was overall 0.72 [95% confidence interval (CI) 0.60-0.83] and 2.22 (95% CI 1.90-2.53) among those who experienced ≥1 fall. The following drug classes showed significant associations: antiparkinsonian medication [IRR 2.68 (95% CI 1.59-4.51)], thyroid therapy [IRR 1.40 (95% CI 1.08-1.81)], and systemic corticosteroids [IRR 0.33 (95% CI 0.13-0.81)]. Among fall-risk-increasing drugs only antiepileptics [IRR 2.16 (95% CI 1.10-4.24)] and urologicals [IRR 2.47 (95% CI 1.33-4.59)] were associated with falls in those participants without a prior fall history at baseline. CONCLUSION AND IMPLICATIONS: Additional drug classes, such as antiparkinsonian medication, thyroid therapy, and systemic corticosteroids, might be associated with falls in older adults, possibly representing pharmacological effects on the musculoskeletal and central nervous systems. Further evaluations in larger study populations are recommended.

CYP2D6 in the Brain: Potential Impact on Adverse Drug Reactions in the Central Nervous System-Results From the ADRED Study.

Cytochrome P450 (CYP) 2D6 is a polymorphic enzyme expressed in the central nervous system (CNS), important in drug metabolism and with a potentially constitutive role in CNS function such as vigilance. This study aimed to analyze variability in CYP2D6 activity linked to vigilance-related adverse drug reactions (ADRs) in the CNS. A dataset of N = 2939 ADR cases of the prospective multicenter observational trial in emergency departments (EDs) (ADRED; trial registration: DRKS-ID: DRKS00008979) was analyzed. Dizziness as the most frequent reported CNS ADR symptom (12.7% of patients, n = 372) related to vigilance was chosen as the outcome. The association of dizziness with CYP2D6 activity markers was analyzed. The number of CYP2D6 substrates taken, a CYP2D6 saturation score (no, moderate, and strong saturation), a CYP2D6 saturation/inhibition score (no, weak, moderate, and strong), and composed CYP2D6 activity using a genotyped subsample (n = 740) calculating additive effects of genotype and CYP2D6 saturation by drug exposure were used as CYP2D6 activity markers. Effects were compared to other frequent nonvigilance-related CNS ADR symptoms (syncope and headache). Secondary analyses were conducted to control for other ADR symptoms frequently associated with dizziness (syncope, nausea, and falls). The majority of all patients (64.5%, n = 1895) took at least one drug metabolized by CYP2D6. Around a third took a CNS drug (32.5%, n = 955). The chance to present with drug-related dizziness to the ED increased with each CYP2D6 substrate taken by OR 1.11 [1.01-1.23]. Presenting with drug-related dizziness was more likely with CYP2D6 saturation and saturation/inhibition (both OR 1.27 [1.00-1.60]). The composed CYP2D6 activity was positively associated with dizziness (p = 0.028), while poorer activity affected patients more often with dizziness as an ADR. In contrast, nonvigilance-related ADR symptoms such as syncope and nausea were not consistently significantly associated with CYP2D6 activity markers. This study shows an association between the number of CYP2D6 substrates, the predicted CYP2D6 activity, and the occurrence of dizziness as a CNS ADR symptom. As dizziness is a vigilance-related CNS symptom, patients with low CYP2D6 activity might be more vulnerable to drug-related dizziness. This study underlines the need for understanding individual drug metabolism activity and individual risks for ADRs.

Adverse Drug Reactions in the Emergency Department: Is There a Role for Pharmacogenomic Profiles at Risk?-Results from the ADRED Study.

Individual differences in required drug dosages exist based on the pharmacogenomic (PGx) profiles. This study aimed to assess associations between PGx profiles and adverse drug reactions (ADR) that lead to admissions to the emergency department (ED). ADR cases of the prospective multi-center observational trial in EDs (ADRED study) were analyzed (n = 776) together with the relevant PGx phenotypes of the enzymes CYP2D6, CYP2C19, CYP2C9, and VKORC1. Overall, the allele frequency distribution in this cohort did not differ from the population frequencies. We compared the frequencies of phenotypes in the subgroups with the drugs suspected of certain ADR, in the remaining cases. The frequency distribution of CYP2C19 differed for the ADR bleeding cases suspected of clopidogrel (p = 0.020). In a logistic regression analysis, higher CYP2C19 activity (OR (95% CI): 4.97 (1.73-14.27)), together with age (1.05 (1.02-1.08)), showed an impact on the clopidogrel-suspecting ADRs, when adjusting for the clinical parameters. There was a trend for an association of phenprocoumon-risk profiles (low VKORC1 or CYP2C9 activity) with phenprocoumon-suspecting ADRs (p = 0.052). The PGx impact on serious ADRs might be highest in drugs that cannot be easily monitored or those that do not provoke mild ADR symptoms very quickly. Therefore, patients that require the intake of those drugs with PGx variability such as clopidogrel, might benefit from PGx testing.

Phenprocoumon Dose Requirements, Dose Stability and Time in Therapeutic Range in Elderly Patients With CYP2C9 and VKORC1 Polymorphisms.

BACKGROUND: Dose requirements of vitamin K antagonists are associated with CYP2C9 and VKORC1, but, compared to warfarin, less data is available about phenprocoumon. Furthermore, the effects on dose stability and anticoagulation quality are still unclear. METHODS: Aim was to scrutinize phenprocoumon dose requirements, dose stability and anticoagulation quality in association to CYP2C9 and VKORC1 in a natural cohort of elderly primary care patients. As a subgroup within the IDrug study, phenprocoumon treated patients with at least two INR values within three months before enrollment (n = 209) were analyzed concerning average weekly dose, standard deviation of weekly dose (intra-subject variability), constant dose (yes/no), average INR and TTR grouped by CYP2C9 and VKORC1 (and combinations). RESULTS: Average weekly dose per patient was 14.4 ± 5.3 mg, 11.9 ± 4.0 mg and 11.2 ± 4.3 mg in CYP2C9 wildtypes, *2 and *3 carriers (p < .0001) and 16.0 ± 4.2 mg, 13.3 ± 5.1 mg and 8.0 ± 2.7 mg per week in VKORC1 CC, CT and TT genotypes, respectively (p < .0001). Significant differences concerning intra-subject variability were detected among all groups (p < .0001) with the smallest variability in CYP2C9*3 carriers. TTR medians were 75.4%, 79.4% and 100% in wildtypes, *2 and *3 carriers, respectively (p = 0.0464). The proportion of patients with perfect control was highest among *3 carriers, but this result was not significant (p = 0.0713). DISCUSSION: Our analyses support the results of previous investigations regarding genotype-associated dose requirements and raise the hypothesis that dose stability and anticoagulation quality may be increased in CYP2C9*3 carriers. However, our data should be treated cautiously due to the small sample size. CLINICAL TRIAL REGISTRATION: German Clinical Trials Register, identifier DRKS00006256.

Potential Drug-Drug Interactions in a Cohort of Elderly, Polymedicated Primary Care Patients on Antithrombotic Treatment.

INTRODUCTION: Drug-drug interactions (DDIs) are an important risk factor for adverse drug reactions. Older, polymedicated patients are particularly affected. Although antithrombotics have been detected as high-risk drugs for DDIs, data on older patients exposed to them are scarce. METHODS: Baseline data of 365 IDrug study outpatients (≥ 60 years, use of an antithrombotic and one or more additional long-term drug) were analyzed regarding potential drug-drug interactions (pDDIs) with a clinical decision support system. Data included prescription and self-medication drugs. RESULTS: The prevalence of having one or more pDDI was 85.2%. The median number of alerts per patient was three (range 0-17). For 58.4% of the patients, potential severe/contraindicated interactions were detected. Antiplatelets and non-steroidal anti-inflammatory drugs (NSAIDs) showed the highest number of average pDDI alert involvements per use (2.9 and 2.2, respectively). For NSAIDs, also the highest average number of severe/contraindicated alert involvements per use (1.2) was observed. 91.8% of all pDDI involvements concerned the 25 most frequently used drug classes. 97.5% of the severe/contraindicated pDDIs were attributed to only nine different potential clinical manifestations. The most common management recommendation for severe/contraindicated pDDIs was to intensify monitoring. Number of drugs was the only detected factor significantly associated with increased number of pDDIs (p < 0.001). CONCLUSION: The findings indicate a high risk for pDDIs in older, polymedicated patients on antithrombotics. As a consequence of patients' frequently similar drug regimens, the variety of potential clinical manifestations was small. Awareness of these pDDI symptoms and the triggering drugs as well as patients' self-medication use may contribute to increased patient safety.

Adverse Drug Reactions (ADR) and Emergencies.

BACKGROUND: Adverse drug reactions (ADR) are a common reason for emergency room visits and for hospitalization. An ADR is said to have occurred when the patient's symptoms and signs are considered to be possibly, probably, or definitely related to the intake of a drug. METHODS: In four large hospital emergency departments, one in each of four German cities ( Ulm, Fürth, Bonn, and Stuttgart), the percentage of suspected ADR cases among all patients presenting to the emergency room was determined during a 30-day period of observation. ADRs were ascertained by screening the digital records of all patients seen in the emergency room; causality was assessed as specified by the WHO-UMC (Uppsala Monitoring Center). RESULTS: ADR were sought in a total of 10 174 emergency department visits. 665 cases of suspected ADR were found, yielding a prevalence of 6.5%. The prevalence of ADR among patients with documented drug intake was 11.6%. Among the patients with documented suspected ADRs, 89% were hospitalized (in contrast to the 43.7% hospitalization rate in the entire group of 10 174 emergency department visits). A possible causal relationship between the patient's symptoms and signs and the intake of a drug was found in 74-84% of cases. Patients with ADR were found to be taking a median of 7 different drugs simultaneously. CONCLUSION: Adverse drug reactions are a relevant cause of emergency department visits, accounting for 6.5% of the total visits in this study, and often lead to hospital admission. The ADRED (Adverse Drug Reactions in Emergency Departments) study, which is now being conducted, is intended to shed further light on their causes, patient risk factors, and potential avoidability.