Polypharmacy, aging and potential drug-drug interactions in outpatients in Taiwan: a retrospective computerized screening study

Potential drug-drug interaction and its determinants among patients with cancer receiving chemotherapy in oncology centres of Northwest Ethiopia: an institutional-based cross-sectional study

OBJECTIVE

The study was conducted to assess potential drug-drug interactions (PDDIs) and its determinants among patients with cancer receiving chemotherapy.

DESIGN AND SETTING

An institutional-based cross-sectional study was used. This study was conducted from 1 June 2021 to 15 December 2021, in Northwest Ethiopia oncology centres.

PARTICIPANTS

All eligible patients with cancer received a combination of chemotherapy.

OUTCOMES

The prevalence and severity of PDDIs were evaluated using three drug interaction databases. Characteristics of participants were presented, arranged and summarised using descriptive statistics. The predictors and outcome variables were examined using logistic regression. The cut-off point was a p value of 0.05.

RESULTS

Of 422 patients included in the study, 304 patients were exposed to at least one PDDI with a prevalence of 72.1% (95 % CI: 68% to 76%) using three drug interaction databases. There were varied reports of the severity of PDDI among databases, but the test agreement using the kappa index was 0.57 (95% CI: 0.52 to 0.62, p=0.0001) which is interpreted as a moderate agreement among three databases. Patients aged ≥50 years old had the risk to be exposed to PDDI by odds of 3.1 times (adjusted OR (AOR)=3.1, 95% CI (1.8 to 5.3); p=0.001) as compared with patients <50 years old. Similarly, patients with polypharmacy and comorbidity were more likely to be exposed to PDDI than their counterparts (AOR=2.4, 95% CI (1.4 to 4.1); p=0.002 and AOR=1.9, 95% CI (1.1 to 3.4); p=0.02, respectively).

CONCLUSION

The main finding of this study is the high prevalence of PDDI, signifying the need for strict patient monitoring for PDDIs among patients with cancer receiving chemotherapy. We suggest the use of at least three drug databases for quality screening. Patients with an age ≥50 years old, polypharmacy and comorbidity were significantly associated with PDDIs. The establishment of oncology clinical pharmacists and computerised reminder mechanisms for PDDIs through drug utilisation review is suggested.

Potential drug-drug interactions in adults receiving oral anticoagulant and antiaggregant therapy

BACKGROUND

Anticoagulant and antiaggregant drugs are drug groups with high mortality and the most common cause of malpractice.

RESEARCH DESIGN AND METHODS

18 and 65 years were scheduled for pharmacotherapy in the Family Health Center. 122 patients during their anticoagulant and/or antiaggregant treatment were evaluated in terms of drug-drug interactions.

RESULTS

Drug-drug interactions were detected in 89.7% of the patients included in the study. A total of 212 drug-drug interactions were found in 122 patients. Of these, 12 (5.6%) were identified as A, 16 (7.5%) B, 146 (68.6%) C, 32 (15.2%) D and 6 (2.8%) X risk category. The number of DDI was found to be significantly higher in patients aged between 56 and 65 years. The most drug interactions are significantly higher in the C and D categories, respectively. The most predicted clinical outcomes of DDI's were increased in the therapeutic effect and adverse/toxic reactions.

CONCLUSIONS

Contrary to expectations, it is seen that although polypharmacy is relatively less in patients aged 18-65 years compared to patients over 65 years of age, it is very important to detect drug interactions in this age group in terms of safety, efficacy and treatment benefit in terms of drug-drug interaction.

Factors associated with a basic common drug-drug interaction knowledge among emergency department medical personnel

Background

Drug-drug interactions (DDIs) are common but less concerning in clinical practice of time-sensitive situations. We aimed to identify factors associated with a basic common DDI knowledge among an emergency physician (EP), an emergency medicine resident (EMR), and an emergency care nurse (ECN).

Methods

This was a prospective cross-sectional study. EP, EMR, and ECN did the examination (multiple-choice questions, 40 points) about common DDI. Prespecified factors associated with examination scores were profession, longer emergency medicine experience, pharmacological training, last advanced cardiovascular life support (ACLS) training, DDI checker book, and application user experience. The outcome was an examination score to evaluate the ability of DDI knowledge. Univariable and multivariable means regressions were used.

Results

A total of 244 participants were enrolled. Factors associated with high examination score were EP (unadjusted mean difference 3.3 points, 95% confidence interval [CI] 2.1 to 4.5, p < 0.001), EMR (2.1, 95% CI 0.7 to 3.5, p 0.005) compared to ECN. Last ACLS training within 2 years (3.7, 95% CI 0.7 to 6.6, p 0.015), 2–4 years (3.4, 95% CI 0.4 to 6.5, p 0.027), and ≥4 years (4.4, 95% CI 1.2 to 7.6, p 0.007) were higher score than no ACLS training. Moreover, the DDI checker application experience user (1.7, 95% CI 0.6 to 2.8, p 0.003) also had a high score compared to the non-experienced user. After adjustment for all factors, EP (adjusted mean difference 3.3 points, 95% CI 1.8 to 4.7, p < 0.001), EMR (2.5, 95% CI 0.6 to 4.3, p 0.010) were higher scores compared to ECN. Meanwhile, the last ACLS training ≥4 years (3.3, 95% CI 0.1 to 6.6, p 0.042) was a higher score than no ACLS training.

Conclusion

EP, EMR, and the last ACLS training ≥4 years were associated with higher DDI knowledge than ECN and no ACLS training, respectively.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40360-022-00623-0.

Assessment of potential drug–drug interactions among outpatients in a tertiary care hospital: focusing on the role of P-glycoprotein and CYP3a4 (retrospective observational study)

Background

Selecting a medicine has a significant impact on the quality of therapy including efficacy and safety. P-glycoprotein and CYP3A4 share several common substrates known as bi-substrates. Both play major role in the pharmacokinetics and pharmacodynamics when over or under expressed.

Objective

The study aimed to assess the Drug–Drug Interaction (DDI) related to P-glycoprotein (P-gp) and Cytochrome P450-3A4 (CYP3A4), to predict their clinical outcomes and also to discover prospective predictors of pDDIs.

Methods

The subjects in this retrospective study ranged in age from 18 to 95 years with polypharmacy prescriptions. Information was gathered through patient medical records. Based on Micromedex and previous literature studies, medications prescribed to the patients were observed for pDDIs according to risk rating scale for drug interactions.

Results

A total of 504 patients (160 males and 344 females) were included in the study. The mean of pDDI seen in the patients was 1.66 ± 1.48 and total 825 pDDIs were discovered. The factors significantly associated with having ≥1 pDDIs included: taking ≥5 medicines (OR 1.747), increased age (OR 1.026) increased comorbidities (OR 1.73).

Conclusion

In prescriptions, a considerable number of probable DDI were discovered. Therefore, careful selection of drugs and identification of mechanisms for DDI is needed to lower the frequency of pDDI.

Advanced Medication Alert System Decreased Hospital-Based Outpatient Duplicated Medications: A Longitudinal Hospital Cohort Study

OBJECTIVES

This study aimed to examine the associations between adoption of an advanced medication alert system and decreases in hospital-based outpatient duplicated medication rates in Taiwan.

METHODS

The unit of analysis was the hospital. We merged the hospital medication alert system adoption survey data and Taiwan National Health Insurance outpatient claims data. The observation time was 1998 to 2011, divided into 5 periods (T1-T5). The analysis included 216 hospitals, and outcome variable was hospital-based outpatient duplicated medication rates. The system adoption time frame, hospital accreditation level, and number of drugs per prescription were defined as predicted variables. A generalized estimating equation regression model was used.

RESULTS

Adoption of the advanced medication alert system gradually increased, such that 100% of medical centers and 84% of regional hospitals, but less than 50% of district hospitals, had systems by T5. The hospital-based outpatient duplicated medication rate continually decreased, from 29.8% to 11.2%. The generalized estimating equation model showed rates of duplicated medications of b = -8.44 at T2 and b = -17.88 at T5 (P < 0.001) compared with T1. Medical centers and regional hospitals demonstrated much lower duplication rates (b = -13.71, b = -6.82; P < 0.001) compared with district hospitals. Hospitals with more medications per prescription had higher duplication rates than did hospitals with fewer items.

CONCLUSIONS

Hospitals accredited at higher levels tended to have advanced medication alert systems. Hospitals that implemented advanced systems decreased hospital-based outpatient duplicated medications, avoiding a potential risk due to inappropriate medication use.

Drug–drug interactions among hospitalized elderly in patients at medical wards of Northwest Ethiopia’s Comprehensive Specialized Hospitals: A multicenter observational study

Objective:

Drug–drug interactions are of major concern due to links to untoward drug effects, hospitalizations, and serious health impacts. Elderly patients are more predisposed to drug interactions than younger patients. The present study aimed to find out the prevalence of drug–drug interactions at North West Ethiopian compressive specialized hospitals’ Internal Medicine wards.

Methods:

From 30 April to 30 July 2021 GC, a multicenter prospective observational study was conducted at north Ethiopian specialized hospitals. Data was collected by using a structured questionnaire adapted from different literature and medical records at the North West Ethiopian Comprehensive Specialized Hospitals’ Internal Medicine wards during the study period. Thereafter checked the completeness of the collected data was checked drug–drug interactions by using Medscape. Epi data version 4.6.2 software was used as data clearance and STATA version 14.1 was used for further data analysis.

Result:

A total of 389 subjects participated in the study of which more than half (55.53%) of them were female with a mean (SD) age of 68.9 ± 7.46 years. A total of 641 drug–drug interactions were detected in this investigation of which, 225(35.1%) were major, 299(46.6%) were significant interactions, and 117(18.3%) were minor interactions. Hospital stay (AOR = 5.95 CI: 3.49–10.12), retire (AOR = 6.71 CI: 1.26–35.78), 5–9 drugs (AOR = 5.30 CI: 2.91–9.67) and more than 10 drugs (AOR = 8.03 CI: 2.47–26.07) were important risk factors for drug–drug interactions.

Conclusion:

The findings of this study suggest that drug–drug interactions were high among hospitalized elderly patients. The presence of polypharmacy, to be retired, and hospital stayed were all found to be strongly linked with drug–drug interactions.

The effects of a pharmacist-led medication review in a nursing home: A randomized controlled trial

BACKGROUND

In this study, an intensive review of pharmaceutical care for elderly patients was conducted in a Veterans Administration nursing home in Taiwan and its effects were evaluated.

METHODS

One hundred participants were enrolled in this randomized controlled study with even distribution. The inclusion criteria were age 65 years or older, prescriptions for at least 5 oral medicines daily, and ≥2 chronic diseases, for the period May 2013 to October 2014. Subjects were excluded if they had previously been included in an intensive medication review conducted by a pharmacist. The primary outcomes were numbers of drugs prescribed, potential inappropriate medications, and numbers of drug-related problems. The secondary outcomes were self-reported medical usages, measurements of quality of life, results of a satisfaction survey, and health status.

RESULTS

A total of 80 cases (42 in the intervention group with medication reconciliation and 38 in the control group without medication reconciliation) completed the study. Baseline characteristics were not statistically different between the 2 groups. The overall prevalence of potential inappropriate medication was 74.3%. There were no differences between the 2 groups, with the exception of "medical problems," which showed a significantly higher prevalence in the intervention group (P < .05). The intervention group reported greater satisfaction regarding pharmacist visits and medication compliance (P < .01). The mean number of drug-related problems was significantly lower after the intervention (P < .01).

CONCLUSION

In this study, the intensive review of the elderly patients' medications revealed that the only significant effect of pharmaceutical care was on "all outcomes." A possible reason for this is the rather advanced ages of some patients who needed a considerable number of medications to treat several chronic diseases. Another reason may be the small sample size. However, participants who received the pharmacist intervention did have higher satisfaction with medication reconciliation and fewer drug-related problems.

Potential drug-drug interactions in the era of integrase strand transfer inhibitors: a cross-sectional single-center study in Japan

BACKGROUND

Potential drug-drug interactions (PDDIs) commonly occur because of aging and comorbidities in people living with human immunodeficiency virus (HIV; PLWH). Protease inhibitors and non-nucleoside reverse transcriptase inhibitors have been reported to cause PDDIs in these patients. However, there are few reports of PDDIs in the era of treatment using integrase strand transfer inhibitors. Therefore, we investigated PDDIs in Japanese PLWH receiving antiretroviral drugs (ARVs).

METHODS

This was a cross-sectional observational study conducted in Japanese outpatients. All eligible patients who had received ARV therapy for at least 48 weeks were enrolled. The primary endpoint was the incidence of PDDIs detected using the Lexicomp® interface.

RESULTS

Of the 71 eligible patients, 51 (71.8%) were prescribed concomitant non-ARV medications. In 21 patients (29.6%), PDDIs with the potential to reduce the effects of ARVs occurred, although the HIV load was suppressed in all cases. Polypharmacy (the use of ≥5 non-ARVs) was observed in 25 patients (35.2%). There was a significantly higher median number of non-ARV medications in the PDDI group than in the non-PDDI group (6 vs. 3, P <  0.001). Furthermore, the proportion of patients on polypharmacy was significantly higher in those with PDDIs than in those without PDDIs (81.0% vs. 26.7%, P <  0.001).

CONCLUSIONS

The incidence of PDDIs is relatively high in Japanese PLWH, even in the era of treatment using integrase strand transfer inhibitors. Therefore, it is important for patients and health care providers to be constantly aware of PDDIs associated with ARV treatment.

Predictors of poor glycemic control among type 2 diabetes mellitus patients treated with antidiabetic medications: A cross-sectional study in China

This study aimed to clarify of the predictors of poor glycemic control in type 2 diabetes mellitus (T2DM) patients treated with antidiabetic medications in China.This study was a retrospective, cross-sectional study based on SuValue database. T2DM patients aged 18 years or older performing glycosylated hemoglobin A1c (HbA1c) examinations from January 1st, 2018 to December 31st, 2018 were included and have been treated with antidiabetic medications for at least 6 months. HbA1c < 7.0% was defined as adequate glycemic control. Multivariate analysis was performed for the factors associated with poor glycemic control.A total of 13972 T2DM patients were included in this study. The adequate glycemic control rate was 44.04% (n = 6153). In the multivariate analysis, predictors of poor glycemic control include longer T2DM duration (5-10 years vs <5 years and >10 years vs <5 years, odds ratio [OR] = 1.499 and 1.581, P < .001 and P = .008), myocardial infarction (OR = 1.141, P = .041), diabetic neuropathy (OR = 1.409, P < .001), secondary hospital (OR = 1.877, P < .001), underdeveloped regions (OR = 1.786, P < .001), insulin only (OR = 3.912, P < .001), combination of oral antidiabetic agents and/or insulin use (P < .001).In conclusion, longer T2DM duration, secondary hospital, myocardial infarction, diabetic neuropathy, undeveloped regions and use of polypharmacy and insulin were associated with poor glycemic control among T2DM patients treated with antidiabetic medications. Patient education and training of health care providers may be short-term strategy to achieve adequate glycemic control.

Risk factors for potential drug-drug interactions in patients with myasthenia gravis

OBJECTIVES

Our aim was to determine risk factors for and frequency of potential drug-drug interactions (pDDIs) among hospitalized patients with myasthenia gravis (MG).

METHODS

This was a retrospective cross-sectional study of the-first time hospitalized MG patients or patients hospitalized because of the exacerbation of MG at the Neurology Clinic of the Clinical Center of Serbia, Belgrade. Medical records and discharge summaries of hospitalized MG patients over a 10-year period were reviewed. The pDDIs were identified by means of Micromedex, and multivariate regression methods were used to reveal potential predictors of number of pDDIs per patient.

RESULTS

The study included 687 patients with MG. In total, 2041 pDDIs were detected in 608 (88.5%) patients. Among the discovered pDDIs, 329 different pDDIs were observed. The most frequent pDDIs were pyridostigmine-prednisone (487patients/70.9%) and aspirin-prednisone (90 patients/13.1%) classified as moderate, and enalapril-potassium chloride (71patients/10.3%) classified as major pDDI. Five drugs (aspirin, insulin, prednisone, cyclosporine, metformin) were responsible for 22.6% of different pDDIs. Dyspnea, generalized form of MG, diabetes mellitus, hypertension, total number of drugs-used, use of antiplatelets were identified as the relevant risk factors for total number of pDDIs (R2 = 0.626,F = 73.797, p < 0.001), while age of patients and history of cancer were inversely correlated with such an outcome.

CONCLUSION

The frequency of the pDDIs in hospitalized MG patients is high, and adversely influenced by dyspnea, generalized MG, diabetes mellitus, hypertension, total number of drugs-used and use of antiplatelets.

Data Sharing and Privacy in Pharmaceutical Studies

Adverse drug events have been a long-standing concern for the wide-ranging harms to public health, and the substantial disease burden. The key to diminish or eliminate the impacts is to build a comprehensive pharmacovigilance system. Application of the "big data" approach has been proved to assist the detection of adverse drug events by involving previously unavailable data sources and promoting health information exchange. Even though challenges and potential risks still remain. The lack of effective privacy-preserving measures in the flow of medical data is the most important Accepted: one, where urgent actions are required to prevent the threats and facilitate the construction of pharmacovigilance systems. Several privacy protection methods are reviewed in this article, which may be helpful to break the barrier.

Frailty status changes are associated with healthcare utilization and subsequent mortality in the elderly population

BACKGROUND

This study determined (1) whether a change in frailty status after a 1 year follow up is associated with healthcare utilization and evaluated (2) whether a change in frailty status after a 1 year follow up and health care utilization are associated with all-cause mortality in a sample of Taiwan population.

METHODS

This work is a population-based prospective cohort study involving residents aged ≥65 years in 2009. A total of 548 elderly patients who received follow-ups in the subsequent year were included in the current data analysis. Fried frailty phenotype was measured at baseline and 1 year. Information on the outpatient visits of each specialty doctor, emergency care utilization, and hospital admission during the 2 month period before the second interview was collected through standardized questionnaires administered by an interviewer. Deaths were verified by indexing to the national database of deaths.

RESULTS

At the subsequent 1 year follow-up, 73 (13.3%), 356 (64.9%), and 119 (21.7%) elderly participants exhibited deterioration, no change in status, and improvement in frailty states, respectively. Multivariate logistic analysis showed the high risk of any type of outpatient use (odds ratios [OR] 1.94, 95% confidence interval [CI] 1.02-3.71) among older adults with worse frailty status compared with those who were robust at baseline and had unchanged frailty status after 1 year. After multivariate adjustment, participants with high outpatient clinic utilization had significantly higher mortality than those with low outpatient clinic visits among unchanged pre-frail or frail (hazard ratios [HR] 2.79, 95% CI: 1.46-5.33) and frail to pre-frail/robust group (HR 9.32, 95% CI: 3.82-22.73) if the unchanged robustness and low outpatient clinic visits group was used as the reference group.

CONCLUSIONS

The conditions associated with frailty status, either after 1 year or at baseline, significantly affected the outpatient visits and may have increased medical expenditures. Combined change in frailty status and number of outpatient visits is related to increased mortality.

Drug-drug Interactions with Warfarin: A Systematic Review and Meta-analysis

AIM

The objective of this paper is to systematically review the literature on drug-drug interactions with warfarin, with a focus on patient-important clinical outcomes.

METHODS

MEDLINE, EMBASE, and the International Pharmaceutical Abstract (IPA) databases were searched from January 2004 to August 2019. We included studies describing drug-drug interactions between warfarin and other drugs. Screening and data extraction were conducted independently and in duplicate. We synthesized pooled odds ratios (OR) with 95% confidence intervals (CIs), comparing warfarin plus another medication to warfarin alone. We assessed the risk of bias at the study level and evaluated the overall certainty of evidence using GRADE.

RESULTS

Of 42,013 citations identified, a total of 72 studies reporting on 3,735,775 patients were considered eligible, including 11 randomized clinical trials and 61 observational studies. Increased risk of clinically relevant bleeding when added to warfarin therapy was observed for antiplatelet (AP) regimens (OR=1.74; 95% CI 1.56, 1.94), many antimicrobials (OR=1.63; 95% CI 1.45, 1.83), NSAIDs including COX-2 NSAIDs (OR=1.83; 95% CI 1.29, 2.59), SSRIs (OR=1.62; 95% CI 1.42, 1.85), mirtazapine (OR=1.75; 95% CI 1.30, 2.36), loop diuretics (OR=1.92; 95% CI 1.29, 2.86), and others. We found a protective effect of proton pump inhibitors (PPIs) against warfarin-related gastrointestinal (GI) bleedings (OR=0.69; 95% CI 0.64, 0.73). No significant effect on thromboembolic events or mortality of any drug group used with warfarin was found, including single or dual AP regimens.

CONCLUSIONS

This review found low to moderate certainty evidence supporting the interaction between warfarin and a small group of medications, which result in increased bleeding risk. PPIs are associated with reduced hospitalization for upper GI bleeding for patients taking warfarin. Further studies are required to better understand drug-drug interactions leading to thromboembolic outcomes or death.

The Prevalence of Selected Potential Drug-Drug Interactions of Analgesic Drugs and Possible Methods of Preventing Them: Lessons Learned From the Analysis of the Real-World National Database of 38 Million Citizens of Poland

Introduction: Drug-drug interactions may lead to poor health outcomes, as well as increased costs and utilization of healthcare services. Unfortunately, real-world data continuously prove high prevalence of potential drug-drug interactions (pDDIs) worldwide. Among identified drivers, ageing, multimorbidity and polypharmacy play a very important role. With these factors being widespread, the need for implementation of strategies minimizing the burden of pDDIs becomes an urgency. This, however, requires a better understanding of the prevalence of pDDIs and the underlying causative factors.

Aim of study: To assess the real-world prevalence of pDDIs and its characteristics in the general population of Poland, using analgesic drugs as a model, and to find out whether pDDIs are caused by prescribing coming from the very same prescribers (co-prescribing).

Methods: A retrospective analysis of the 2018 dispensation data of the National Health Fund (NHF) - the only Polish public healthcare payer organization with nationwide coverage. We searched for selected pDDIs of non-steroidal anti-inflammatory drugs (NSAIDs) with antihypertensives, other NSAIDs (double use), oral glucocorticoids, oral anticoagulants, selective serotonin reuptake inhibitors (SSRIs), serotonin–norepinephrine reuptake inhibitors (SNRIs), and antiplatelet drugs; as well as opioides with SSRIs, SNRIs, gabapentinoids, and benzodiazepines. A pDDI was deemed present if two drugs standing in a possible conflict were dispensed within the same calendar month.

Results: Out of 38.4 million citizens of Poland, 23.3 million were dispensed prescribed drugs reimbursed by NHF in 2018. In this cohort, we have identified 2,485,787 cases of analgesic drug pDDIs, corresponding with 6.47% of the Polish population. Out of these, the most prevalent pDDI was caused by “NSAIDs + antihypertensives” (1,583,575 cases, i.e., 4.12% of the Polish population), followed by “NSAIDs + NSAIDs” (538,640, 1.40%) and “NSAIDs + glucocorticoids” (213,504, 0.56%). The most persistent pDDIs among those studied were caused by “Opioids + Gabapentinoids” (2.19, 95%CI: 2.16–2.22 months). On average, 76.63% of all cases of pDDIs were caused by drugs prescribed by the very same prescribers.

Conclusion: Based on high-quality, nationwide data, we have found a high prevalence of analgesic drugs-related pDDIs in Poland. Over ¾ of the identified pDDIs were caused by co-prescribing, i.e., prescriptions issued by the same prescribers. The significance of the problem, illustrated with our findings on analgesic drugs-related pDDIs in Poland, deserves much more scientific and policymaker attention.

Workload of pharmacists and the performance of pharmacy services

Objective

To evaluate the influence of pharmacists’ dispensing workload (PDW) on pharmacy services as measured by prescription suggestion rate (PSR) and dispensing error rate (DER).

Method

This was an observational study in northern and southern Taiwan’s two largest medical centers, from 2012 to 2018. We calculated monthly PDW as number of prescriptions divided by number of pharmacist working days. We used monthly PSR and DER as outcome indicators for pharmacists’ review and dispensing services, respectively. We used Poisson regression model with generalized estimation equation methods to evaluate the influence of PDW on PSR and DER.

Results

The monthly mean of 463,587 (SD 32,898) prescriptions yielded mean PDW, PSR and DER of 52 (SD 3) prescriptions per pharmacist working days, 30 (SD 7) and 8 (SD 2) per 10,000 prescriptions monthly, respectively. There was significant negative impact of PDW on PSR (adjusted rate ratio, aRR: 0.9786; 95%CI: 0.9744–0.9829) and DER (aRR: 0.9567; 95%CI: 0.9477–0.9658). Stratified analyses by time periods (2012–2015 and 2016–2018) revealed the impact of PDW on PSR to be similar in both periods; but with positive association between PDW and DER in the more recent one (aRR: 1.0086, 95%CI: 1.0003–1.0169).

Conclusions

Reduced pharmacist workload was associated with re-allocation of pharmacy time to provide prescription suggestions and, more recently, decrease dispensing errors. Continuous efforts to maintain appropriate workload for pharmacists are recommended to ensure prescription quality.

The prevalence and severity of potential drug-drug interactions among adult polypharmacy patients at outpatient clinics in Jordan

Objective

To assess the prevalence of potential drug-drug interactions (pDDIs) among polypharmacy patients in Jordan using Lexicomp®. Additionally, this study aims to categorize and rate the identified pDDIs according to interaction risk, severity, and reliability.

Methods

A descriptive cross-sectional study was conducted at six different hospitals representing different public health sectors in Jordan (ministry of health, royal medical services, and university-affiliated hospitals). Polypharmacy patients from outpatient clinics (e.g., cardiology,& and internal medicine) were identified, recruited, and interviewed by clinical pharmacists. pDDIs were assessed using the Lexicomp® mobile application and classified according to interaction risk rating, severity, and reliability rating. Furthermore, the prevalence of pDDIs across chronic medical conditions was assessed. P-value <0.05 was considered as significant.

Results

A total of 801 patients with polypharmacy were identified. The average number of drugs per patient was 6.6 ± 1.96, with an average of 4.2 ± 3.0 pDDIs per patient. Potential drug-drug interactions were detected in 769 patients (96%), with a total of 3359 interactions. Blood pressure lowering agents were involved in 39.9% of the pDDIs. Cardiovascular system drugs contributed to the largest share of pDDIs (46.6%). While diuretics had the major share of interactions among cardiovascular system drugs (16.2%), drugs used in diabetes had the highest share across all groups (17.1%). The majority of pDDIs were of “C” risk rating with a moderate interaction severity, whilst 1.6% of pDDIs could have been avoided in the first place as the concurrent administration of these agents is contraindicated (i.e., risk rating X). Patients with cardiovascular diseases, diabetes, chronic obstructive pulmonary disease, gout, and chronic kidney disease were associated with the highest number of potential drug-drug interactions.

Conclusion

Our study showed that 96% of polypharmacy patients at outpatient clinics have at least one pDDI. Almost half of the detected interactions involved cardiovascular medications. The majority of these pDDIs had moderate severity, with no more than 10% of the interactions requiring therapy modification.

Effect of Pharmacist Intervention on a Population in Taiwan with High Healthcare Utilization and Excessive Polypharmacy

Patients with high healthcare utilization are at increased risk of polypharmacy and drug interactions. This study investigated the changes in the number of medications, drug interactions and interaction severity in high frequency outpatients with polypharmacy at hospitals and clinics in Taiwan after home pharmaceutical care, to understand the effectiveness of interventions by pharmacists. This was a retrospective observational study. Cases with excessive polypharmacy (10+ drugs) were selected from the Pharmaceutical Care Practice System database of the Taiwan Pharmacist Association in 2017. After the home care intervention, the number of drug types used decreased 1.89-fold (p < 0.001), and the number of medications fell 61.6%. The incidence of drug interaction was 93.82%. In an average case, the incidence of drug interaction after the pharmacist intervention decreased 0.6-fold (p < 0.001). The drug most commonly causing interactions was aspirin, followed by diclofenac; also common were three used in diabetes, two psycholeptics and two beta blockers. Among 22 cases of severe drug interaction, seven resulted in increased risk of extrapyramidal symptoms and neuroleptic malignant syndrome. By analyzing the relationship between the side effects of individual drugs and the pharmacokinetic T_max, a sequential thermal zone model of adverse drug reactions can be established, the value of which could prompt physicians and pharmacists to intervene in order to prevent adverse events. It is concluded that home pharmaceutical care by pharmacists can significantly reduce the number of medications and interactions in patients with excessive polypharmacy and high healthcare utilization.

Concurrent prescribing: Evaluation of its knowledge among dentists

Introduction

Considering the staggering number of drugs being prescribed to the patients for dental ailments, the ability of the dentists to recognize potential drug-drug interactions (DDIs) is essential to reduce their occurrence. This study aims to assess the dentist's ability to recognize the potentially clinically significant DDIs in clinical practice.

Subjects and Methods

This questionnaire-based study was carried out among the dentists working at private tertiary care teaching dental hospitals in Jaipur city. Eighty-five dentists working as faculty members in various departments and having postgraduate degree in their respective specialty were enrolled after taking their written informed consent. A prevalidated close-ended questionnaire was given to the respondents to check their knowledge about common DDI possible in clinical dentistry practice.

Statistical Analysis Used

Statistical analysis was done using descriptive statistics. Data were collected in a predesigned Microsoft Excel 2010. Continuous variables were presented as mean values ± standard deviation, and categorical variables were presented as percentages.

Results

Among 85 dentists recruited for the study, no one had knowledge about all the common DDIs in dental practice. The participants could correctly identify only 47.86% of drug pairs. Drug information services available on the Internet were the most common source (32%) of knowledge of DDIs among them. Knowledge of the prescribed drug (40%) and complete drug history including over-the-counter and herbal products (35%) were the two important ways identified by them for avoiding unwanted drug interactions in clinics.

Conclusion

The study revealed that the existing knowledge of the dentists was not adequate. Hence the knowledge of the dentists about DDIs pertinent to dentistry should be enriched and should be reinforced by arranging training sessions at constant intervals of time.

Epidemiology of potential drug-drug interactions in elderly population admitted to critical care units of Peshawar, Pakistan

BACKGROUND

Aging population, is a reality in many countries because of improvement in the health care, patient safety and other supplemental factors. Pharmacotherapy in this population must be evaluated due to their higher susceptibility to adverse drug outcomes, like potential drug-drug interactions (PDDIs). Research in this regard is limited particularly in developing countries. The aim of the study was to evaluate the prevalence and associated factors in this population.

METHODS

The multicentered study evaluated the prevalence of potential drug-drug interactions and associated factors in elderly population at critical care units in Peshawar, Pakistan. Potential drug-drug interactions were evaluated using Micromedex DrugReax, while statistical analysis was performed using SPSS.

RESULTS

A total of 70.17% elderly patients were observed to have at least one PDDI. A significant association was observed between presence of PDDIs and number of prescribed drugs, duration of stay and age (p < 0.05). A total of 3019 PDDIs were observed, attributing to 225 drug pairs. Prevalent PDDIs were of moderate severity, good documentation and pharmacodynamic in nature. One-way ANOVA revealed a significant difference in the means of PDDIs between Northwest general hospital and the rest of the hospitals. Moreover, there was a significant difference in the means of PDDIs of CCU and SU with rest of the units.

CONCLUSION

The prevalence of PDDIs was observed to be high in elderly population which can be managed by avoiding or managing a limited number of drug combinations. Such studies are necessary to evaluate the risks of these PDDIs in a population which is already physiologically compromised.

Comparative study of antiretroviral drug regimens and drug-drug interactions between younger and older HIV-infected patients at a tertiary care teaching hospital in South Korea

Background

With the advent of combination antiretroviral therapy (ART), people living with HIV have lived to older age. So they have experienced age-related illnesses and have taken non-antiretroviral (ARV) medications to manage these illnesses. The aims of this study were to investigate the use patterns of ARV agents in HIV-positive patients by age and to evaluate potential or contraindicated drug-drug interactions (DDIs) between ARV and non-ARV.

Methods

This study was retrospectively conducted with HIV-infected patients receiving ART medications between October 2011 and September 2017 at Chonbuk National University Hospital in South Korea. Data were collected by reviewing patients' electronic medical charts.

Results

Among 207 patients diagnosed with HIV infection, 183 (86.9% males; 104 aged <50 years and 79 aged ≥50 years) were selected based on inclusion criteria. In 2017, the most frequently prescribed ART regimen was nucleoside reverse transcriptase inhibitors (NRTIs)/integrase strand transfer inhibitors (INSTIs; total, 66.3%; <50 years, 36.3%; ≥50 years, 30.0%) followed by NRTIs/protease inhibitors (PIs; total, 23.8%; <50 years, 15.0%; ≥50 years, 8.8%). In 2017, the most frequently prescribed NRTI combination was abacavir/lamivudine (total, 34.4%; <50 years, 20.6%; ≥50 years, 13.8%) followed by tenofovir alafenamide/emtricitabine (FTC; total, 31.3%; <50 years, 16.3%; ≥50 years, 15.0%) and tenofovir disoproxil fumarate/FTC (total, 28.1%; <50 years, 16.9%; ≥50 years, 11.3%). In 2017, elvitegravir (EVG)/cobicistat (COBI; total, 57.1%; <50 years, 30.4%; ≥50 years, 26.8%) was most frequently prescribed followed by dolutegravir (total, 32.1%; <50 years, 19.6%; ≥50 years, 12.5%). Potential or contraindicated DDIs between boosted PIs with ritonavir or EVG/COBI and coprescribed drugs occurred most frequently.

Conclusion

Currently, NRTIs/INSTIs is the most frequently prescribed ARV combination. Abacavir/lamivudine, tenofovir alafenamide/FTC, and tenofovir disoproxil fumarate/FTC are the most used NRTIs, and EVG/COBI followed by dolutegravir is the most prescribed INSTIs. Potential or contraindicated DDIs occur mainly between boosted PIs or EVG/COBI and non-ARV medications.

Evaluation of Potential Drug-Drug Interactions with Medications Prescribed to Geriatric Patients in a Tertiary Care Hospital

Background and Objectives

The drugs most commonly implicated in major potential interactions are those used in the day-to-day clinical management of elderly patients with chronic diseases. This study is planned to evaluate the profile of drug-drug interactions in the medications prescribed to elderly population and also to identify the possible predictors for potential drug-drug interactions in the elderly.

Methods

This cross-sectional study included patients aged above 60 years with a minimum of two drugs in the prescriptions. Data were collected from medical prescriptions and patients' medical records. The data collected included demographic characteristics such as age, gender, height, weight, educational status, socioeconomic status, medical history, and medications prescribed. The prescriptions were analyzed for the potential drug interactions using Lexi-Interact™ Online, an online software to check drug-drug interactions.

Results

A total of 209 patients were included in the study, among them 104 (49.8%) were males and 105 (50.2%) were females. The mean number of medications received was 6.53 ± 2.15 per prescription. Around 138 (66%) patients received more than six medications. The mean number of potential drug interactions seen in the prescription of these patients was 3.17 ± 2.78. Around 18.2% patients had more than five drug interactions. Major drug interactions were observed in 21.42% of cases. Around 3.02% of drug interactions belonged to risk category X, i.e., to be avoided. Logistic regression analysis showed that age above 70 years was associated with the presence of drug interactions. Increased number of medication was independently associated with the occurrence of drug interactions. The presence of drug interactions was not associated with increased number of comorbidities.

Conclusion

A significant number of potential drug-drug interactions were seen in the prescriptions of elderly patients. Increasing age and polypharmacy were identified as the predictors of potential drug interactions.

Polypharmacy and potential drug-drug interactions in emergency department patients in the Caribbean

Background Potential Drug-Drug Interactions (DDI) account for many emergency department visits. Polypharmacy, as well as herbal, over-the-counter (OTC) and combination medication may compound this, but these problems are not well researched in low-and-middle-income countries. Objective To compare the incidence of drug-drug interactions and polypharmacy in older and younger patients attending the Emergency Department (ED). Setting The adult ED of a tertiary teaching hospital in Trinidad. Methods A 4 month cross sectional study was conducted, comparing potential DDI in older and younger patients discharged from the ED, as defined using Micromedex 2.0. Main outcome measure The incidence and severity of DDI and polypharmacy (defined as the use of ≥5 drugs simultaneously) in older and younger patients attending the ED. Results 649 patients were included; 275 (42.3%) were ≥65 years and 381 (58.7%) were female. There were 814 DDIs, of which 6 (.7%) were contraindications and 148 (18.2%) were severe. Polypharmacy was identified in 244 (37.6%) patients. Older patients were more likely to have potential DDI (67.5 vs 48.9%) and polypharmacy (56 vs 24.1%). Herbal products, OTC and combination drugs were present in 8, 36.7 and 22.2% of patients, respectively. On multivariate analysis, polypharmacy and the presence of hypertension and ischaemic heart disease were associated with an increased risk of potential DDI. Conclusion Polypharmacy and potential drug-drug interactions are common in ED patients in the Caribbean. Older patients are particularly at risk, especially as they are more likely to be on multiple medications. The association between herbal medication and polypharmacy needs further investigation. This study indicates the need for a more robust system of drug reconciliation in the Caribbean.

Prevalence and predictors of potential drug-drug interactions in patients of internal medicine wards of a tertiary care hospital in India

Background

Drug-drug interactions are a major source of adverse drug events (ADEs). Polypharmacy, age and the number of comorbid conditions are important predictors of adverse drug interactions. ADEs account for up to 5% of hospital admissions per year and an increase in the length of hospital stay.

Objective

To find the prevalence and predictors of potential drug-drug interactions (pDDIs) in patients admitted to the wards of an internal medicine department of a tertiary care hospital.

Method

Patients admitted to internal medicine wards with prescriptions having more than one drug were selected. Demographic details including age, gender, number of comorbid conditions, number of drugs prescribed and the disease for which the patient was admitted were recorded in a case record form. Interactions were checked using Micromedex DrugReax software.

Results

A total of 939 patients were recruited for this study based on inclusion criteria. 433 prescriptions (46%) had one or more pDDIs, with a range of 1-13 drug interactions per prescription. A total of 1395 drug interactions were found, with 866 moderate drug interactions (62%), 435 major interactions (31.1%) and 89 minor interactions (6.3%). During the study period only three contraindicated drug combinations (0.2%) were recorded. A significant association (p<0.01) was found between the number of pDDIs and predictors, age and number of drugs.

Conclusion

A total of 433 prescriptions (46%) had one or more pDDIs. Older patients and those prescribed >6 drugs are at major risk for occurrence of pDDIs. Moderate severity interactions were the highest number followed by major severity interactions.

Clinically relevant potential drug-drug interactions among outpatients: A nationwide database study

BACKGROUND

Adverse drug events due to drug-drug interactions (DDIs) represent a considerable public health burden, also in Slovenia. A better understanding of the most frequently occurring potential DDIs may enable safer pharmacotherapy and minimize drug-related problems.

OBJECTIVES

The aim of this study was to evaluate the prevalence and predictors of potential DDIs among outpatients in Slovenia.

METHODS

An analysis of potential DDIs was performed using health claims data on prescription drugs from a nationwide database. The Lexi-Interact Module was used as the reference source of interactions. The influence of patient-specific predictors on the risk of potential clinically relevant DDIs was evaluated using logistic regression model.

RESULTS

The study population included 1,179,803 outpatients who received 15,811,979 prescriptions. The total number of potential DDI cases identified was 3,974,994, of which 15.6% were potentially clinically relevant. Altogether, 9.3% (N = 191,213) of the total population in Slovenia is exposed to clinically relevant potential DDIs, and the proportion is higher among women and the elderly. After adjustment for cofactors, higher number of medications and older age are associated with higher odds of clinically relevant potential DDIs. The burden of DDIs is highest with drug combinations that increase risk of bleeding, enhance CNS depression or anticholinergic effects or cause cardiovascular complications.

CONCLUSION

The current study revealed that 1 in 10 individuals in the total Slovenian population is exposed to clinically relevant potential DDIs yearly. Taking into account the literature based conservative estimate that approximately 1% of potential DDIs result in negative health outcomes, roughly 1800 individuals in Slovenia experience an adverse health outcome each year as a result of clinically relevant potential interactions alone.

Potentially severe drug-drug interactions among older people and associations in assisted living facilities in Finland: a cross-sectional study

OBJECTIVE

This study aims to assess potentially severe class D drug-drug interactions (DDDIs) in residents 65 years or older in assisted living facilities with the use of a Swedish and Finnish drug-drug interaction database (SFINX).

DESIGN

A cross-sectional study of residents in assisted living facilities in Helsinki, Finland.

SETTING

A total of 1327 residents were assessed in this study. Drugs were classified according to the Anatomical Therapeutic Chemical (ATC) classification system and DDDIs were coded according to the SFINX.

MAIN OUTCOME MEASURES

Prevalence of DDDIs, associated factors and 3-year mortality among residents.

RESULTS

Of the participants (mean age was 82.7 years, 78.3% were females), 5.9% (N = 78) are at risk for DDDIs, with a total of 86 interactions. Participants with DDDIs had been prescribed a higher number of drugs (10.8 (SD 3.8) vs. 7.9 (SD 3.7), p < 0.001). A larger proportion of residents with DDDIs suffered from rheumatoid arthritis or osteoarthritis than those not exposed to DDDIs (24.7% vs. 15.4%, p = 0.030). The most frequent DDDIs were related to the concomitant use of potassium with amiloride (N = 12) or spironolactone (N = 12). Carbamazepine (N = 13) and methotrexate (N = 9) treatments were also frequently linked to DDDIs. During the follow-up, no differences in mortality emerged between the participants exposed to DDDIs and the participants not exposed to DDDIs.

CONCLUSIONS

Of the residents in assisted living, 5.9% were exposed to DDDIs associated with the use of a higher number of drugs. Physicians should be trained to find safer alternatives to drugs associated with DDDIs. KEY POINTS   Potentially severe, class D drug-drug interactions (DDDIs) have been defined in the SFINX database as clinically relevant drug interactions that should be avoided.  • Of the residents in assisted living, 5.9% were exposed to DDDIs that were associated with the use of a higher number of drugs.  • The most frequent DDDIs were related to the concomitant use of potassium with amiloride or spironolactone. Carbamazepine and methotrexate were also linked to DDDIs.  • No difference in mortality was observed between residents exposed to DDDIs and residents not exposed to DDDIs.

Potential drug-drug interactions among elderly patients admitted to medical ward of Ayder Referral Hospital, Northern Ethiopia: a cross sectional study

BACKGROUND

The elderly are considered as special population, as they differ from younger adults in terms of comorbidity, polypharmacy, pharmacokinetics, vulnerability to drug-drug interactions and adverse drug reactions. Despite the fact that the elderly patients are at high risk of having drug interaction and potential adverse outcomes, studies in this regard are scarce in resource limited settings like Ethiopia. The aim of this study was to assess the prevalence and determinants of potential drug-drug interaction in elderly patients admitted to medical ward of Ayder Referral Hospital in Northern Ethiopia.

METHODS

A cross sectional study was conducted among elderly inpatients aged 60 years and above. The study was conducted from February to May 2014. Prescribed drugs being taken concurrently for at least 24 h were included and checked for drug-drug interaction using Micromedex® 2.0 online drug reference. Data were analyzed using statistical software, statistical package for social sciences for windows version 20. Logistic regression model was used to analyze factors associated with occurrence of drug interaction. P value of <0.05 was considered statistically significant.

RESULTS

A total of 140 patients were participated in the study. The mean age (±standard deviation) of participants was 68 (±7) years. Majority (61.4 %) of patients were diagnosed with cardiovascular and/or renal diseases. A total of 814 drugs were prescribed with a mean of 6 (±4) medications per patient during a 13 (±9) days of hospital stay. About two-third (62.2 %) of the respondents were exposed to at least one potential drug-drug interaction. Among these 3.6, 32.9 and 25.7 % of patients had taken contraindicated drug combination, at least one major and at least one moderate drug-drug interaction, respectively. Patients with five or more prescribed medications were four times at risk of having drug-drug interaction (P = 0.00; adjusted odds ratio 4.047; 95 % confidence interval 1.867-8.775).

CONCLUSION

Drug-drug interaction in elderly patients was common in this resource limited set-up. Awareness creation and clinical pharmacist involvement in minimizing the risk associated with potentially harmful drug combinations are needed.

Characteristics of ambulatory care visits to family medicine specialists in Taiwan: a nationwide analysis

Although family medicine (FM) is the most commonly practiced specialty among all the medical specialties, its practice patterns have seldom been analyzed. Looking at data from Taiwan's National Health Insurance Research Database, the current study analyzed ambulatory visits to FM specialists nationwide. From a sample dataset that randomly sampled one out of every 500 cases among a total of 309,880,000 visits in 2012, it was found that 18.8% (n = 116, 551) of the 619,760 visits in the dataset were made to FM specialists. Most of the FM services were performed by male FM physicians. Elderly patients above 80 years of age accounted for only 7.1% of FM visits. The most frequent diagnoses (22.8%) were associated acute upper respiratory infections (including ICD 460, 465 and 466). Anti-histamine agents were prescribed in 25.6% of FM visits. Hypertension, diabetes and dyslipidemia were the causes of 20.7% of the ambulatory visits made to FM specialists of all types, while those conditions accounted for only 10.6% of visits to FM clinics. The study demonstrated the relatively low proportion of chronic diseases that was managed in FM clinics in Taiwan, and our detailed results could contribute to evidence-based discussions on healthcare policymaking and residency training.

Predictors of poor glycaemic control in older patients with type 2 diabetes mellitus

INTRODUCTION

We assessed the predictors of poor glycaemic control among older patients with type 2 diabetes mellitus (T2DM) in Malaysia.

METHODS

This cross-sectional study used the data of 21,336 patients aged ≥ 60 years with T2DM from the Adult Diabetes Control and Management Registry 2008-2009.

RESULTS

Predictors of poor glycaemic control were: age groups 60-69 years (odds ratio [OR] 1.96, 95% confidence interval [CI] 1.66-2.33) and 70-79 years (OR 1.43, 95% CI 1.20-1.71); Malay (OR 1.53, 95% CI 1.41-1.66) and Indian (OR 1.32, 95% CI 1.19-1.46) ethnicities; T2DM durations of 5-10 years (OR 1.46, 95% CI 1.35-1.58) and > 10 years (OR 1.75, 95% CI 1.59-1.91); the use of oral antidiabetic agents only (OR 5.86, 95% CI 3.32-10.34), insulin only (OR 17.93, 95% CI 9.91-32.43), and oral antidiabetic agents and insulin (OR 29.42, 95% CI 16.47-52.53); and elevated blood pressure (OR 1.10, 95% CI 1.01-1.20), low-density lipoprotein cholesterol (OR 1.48, 95% CI 1.38-1.59) and triglycerides (OR 1.61, 95% CI 1.51-1.73). Hypertension (OR 0.71, 95% CI 0.64-0.80), hypertension and dyslipidaemia (OR 0.68, 95% CI 0.61-0.75), pre-obesity (OR 0.89, 95% CI 0.82-0.98) and obesity (OR 0.76, 95% CI 0.70-0.84) were less likely to be associated with poor glycaemic control.

CONCLUSION

Young-old and middle-old age groups (i.e. < 80 years), Malay and Indian ethnicities, longer T2DM duration, the use of pharmacological agents, and elevated blood pressure and lipid levels were associated with poor glycaemic control. The presence of comorbidities, pre-obesity and obesity were less likely to be associated with poor glycaemic control.

The rising tide of polypharmacy and drug-drug interactions: population database analysis 1995-2010

BACKGROUND

The escalating use of prescribed drugs has increasingly raised concerns about polypharmacy. This study aims to examine changes in rates of polypharmacy and potentially serious drug-drug interactions in a stable geographical population between 1995 and 2010.

METHODS

This is a repeated cross-sectional analysis of community-dispensed prescribing data for all 310,000 adults resident in the Tayside region of Scotland in 1995 and 2010. The number of drug classes dispensed and the number of potentially serious drug-drug interactions (DDIs) in the previous 84 days were calculated, and age-sex standardised rates in 1995 and 2010 compared. Patient characteristics associated with receipt of ≥ 10 drugs and with the presence of one or more DDIs were examined using multilevel logistic regression to account for clustering of patients within primary care practices.

RESULTS

Between 1995 and 2010, the proportion of adults dispensed ≥ 5 drugs doubled to 20.8%, and the proportion dispensed ≥ 10 tripled to 5.8%. Receipt of ≥ 10 drugs was strongly associated with increasing age (20-29 years, 0.3%; ≥ 80 years, 24.0%; adjusted OR, 118.3; 95% CI, 99.5-140.7) but was also independently more common in people living in more deprived areas (adjusted OR most vs. least deprived quintile, 2.36; 95% CI, 2.22-2.51), and in people resident in a care home (adjusted OR, 2.88; 95% CI, 2.65-3.13). The proportion with potentially serious drug-drug interactions more than doubled to 13% of adults in 2010, and the number of drugs dispensed was the characteristic most strongly associated with this (10.9% if dispensed 2-4 drugs vs. 80.8% if dispensed ≥ 15 drugs; adjusted OR, 26.8; 95% CI 24.5-29.3).

CONCLUSIONS

Drug regimens are increasingly complex and potentially harmful, and people with polypharmacy need regular review and prescribing optimisation. Research is needed to better understand the impact of multiple interacting drugs as used in real-world practice and to evaluate the effect of medicine optimisation interventions on quality of life and mortality.

Drug-drug interaction software in clinical practice: a systematic review

PURPOSE

Several electronic databases which report the prevalence of drug-drug interactions (DDIs) are used as a tool for evaluation of potentially harmful DDIs. The aim of our review was to evaluate the usability and appropriateness of commercially available electronic databases which assess the prevalence of potential DDIs.

METHODS

The systematic electronic literature search was conducted with the following search terms: "database" AND "software," and "drug-drug interactions" AND "database," and the inclusion and exclusion criteria were applied in order to identify the publications of interest.

RESULTS

A total of 3766 papers were identified by systematic search. After applying inclusion and exclusion criteria, 38 publications were included in the analysis. The most commonly used software in the included studies was Micromedex® Drug-Reax, for which some authors argue to be the most reliable due to highest sensitivity. It gives information about clinical consequences of DDIs, classifies underlying mechanism and onset of the adverse outcome (either rapid, or delayed) as well as severity (such as minor, moderate, or major), and provides the level of evidence which supports this information. This data is also provided by Drug Interaction Facts®, Lexi-Interact®, and Pharmavista®. A small number of studies which compared assessment of DDIs with electronic database and the clinician's assessment showed large discrepancy in number and relevance of detected DDIs. The overlap was in some cases as low as 11 %.

CONCLUSION

The deficiency of clinical relevance of detected DDIs should be addressed in the upcoming research as it would provide more relevant information to the prescribers' in clinical practice.

How common are drug and gene interactions? Prevalence in a sample of 1143 patients with CYP2C9, CYP2C19 and CYP2D6 genotyping

AIM

Drug-drug interactions (DDIs) are a widely recognized major cause of adverse drug reactions, but two other newly described important types of interactions also exist: drug-gene interactions (DGIs) and drug-drug-gene interactions (DDGIs). A drug-gene interaction occurs when a patient's genetic CYP450 type (e.g., CYP2D6 poor metabolizer) affects that patient's ability to clear a drug. A drug-drug-gene interaction occurs when the patient's CYP450 genotype and another drug in the patient's regimen (e.g., a CYP2D6 inhibitor) affect that individual's ability to clear a drug. Their prevalence has not been previously described. This pilot study investigates the frequency of DDIs, DGIs and DDGIs in a sample of CYP450 tested individuals.

MATERIALS & METHODS

The investigators conducted a retrospective analysis of 1143 individuals with known CYP2D6, CYP2C19 and CYP2C9 genotypes. Using the individuals' medication lists and YouScript(®), a software tool to analyze cumulative DDIs and DGIs, the prevalence of DDI, DGI and DDGIs was analyzed.

RESULTS

A total of 1053 potential major or substantial interactions were identified in 501 individuals. DDIs accounted for 66.1% of the total interactions. The remaining 33.9% of interactions were DGIs (14.7%) and DDGIs (19.2%). When compared with DDIs alone, DGIs and DDGIs increased the total number of potentially clinically significant interactions by 51.3%.

CONCLUSION

In the future, identifying DGIs and DDGIs may lead to a more comprehensive method of identifying individuals who are at risk for adverse drug reactions.

Multiple medication use in older patients in post-acute transitional care: a prospective cohort study

Background

Older adults with a range of comorbidities are often prescribed multiple medications, which may impact on their function and cognition and increase the potential for drug interactions and adverse events.

Aims

This study investigated the extent of polypharmacy and potentially inappropriate medications in patients receiving post-discharge transitional home care and explored the associations of polypharmacy with patient characteristics, functional outcomes, and frailty.

Methods

A prospective observational study was conducted of 351 patients discharged home from hospital with support from six Transition Care Program (TCP) sites in two states of Australia. A comprehensive geriatric assessment was conducted at TCP admission and discharge using the interRAI Home Care assessment tool, with frailty measured using an index of 57 accumulated deficits. Medications from hospital discharge summaries were coded using the World Health Organization Anatomical Therapeutic Chemical Classification System.

Results

Polypharmacy (5–9 drugs) was observed in 46.7% and hyperpolypharmacy (≥10 drugs) in 39.2% of patients. Increasing numbers of medications were associated with greater number of comorbid conditions, a higher prevalence of diabetes mellitus, coronary heart disease, chronic obstructive pulmonary disease, dizziness, and dyspnea and increased frailty. At discharge from the program, the non-polypharmacy group (<5 drugs) had improved outcomes in Activities of Daily Living, Instrumental Activities of Daily Living and fewer falls, which was mediated because of lower levels of frailty. The commonest drugs were analgesics (56.8%) and antiulcer drugs (52.7%). The commonest potentially inappropriate medications were tertiary tricyclic antidepressants.

Conclusion

Polypharmacy is common in older patients discharged from hospital. It is associated with frailty, falls, and poor functional outcomes. Efforts should be made to encourage regular medication reviews and rationalization of medications as part of discharge planning. Whether careful deprescribing improves outcomes in frail patients should be the focus of randomized trials.

Prevention of inappropriate prescribing in hospitalized older patients using a computerized prescription support system (INTERcheck(®))

BACKGROUND

Polypharmacy is very common among older adults and can lead to inappropriate prescribing, poor adherence to treatment, adverse drug events and the prevalence of potential drug-drug interactions (DDIs). Electronic prescription database software may help to prevent inappropriate prescribing and minimize the occurrence of adverse drug reactions. INTERcheck(®) is a Computerized Prescription Support System (CPSS) developed in order to optimize drug prescription for elderly people with multimorbidity.

OBJECTIVES

The objectives of this study were (i) to evaluate the applicability of INTERcheck(®) as a means of reviewing the pharmacological profiles of elderly patients hospitalized in an acute geriatric ward in Northern Italy; and (ii) to evaluate the effectiveness of INTERcheck(®) in reducing potentially inappropriate medications (PIMs), potentially severe DDIs and the anticholinergic burden in daily practice.

METHODS

Two samples of elderly patients (aged 65+ years) hospitalized in a geriatric ward in Italy were enrolled throughout 2012. During the first (observation) phase, medications prescribed to 74 patients at admission and discharge were analyzed with INTERCheck(®) without any kind of interference based on information obtained from the software. During the second (intervention) phase, the treatment of 60 patients was reviewed and changed at discharge according to INTERCheck(®) suggestions.

RESULTS

In the observational period, the number of patients exposed to at least one PIM remained unchanged on both admission (n = 29; 39.1 %) and discharge (n = 28; 37.8 %). In the intervention phase, 25 patients (41.7 %) were exposed to at least one PIM at admission and 7 (11.6 %) at discharge (p < 0.001). The number of patients exposed to at least one potentially severe DDI decreased from 27 (45.0 %) to 20 (33.3 %), although the difference was not statistically significant (p = 0.703), while the number of new-onset potentially severe DDIs decreased from 37 (59.0 %) to 9 (33.0 %) [p < 0.001].

CONCLUSIONS

The use of INTERCheck(®) was associated with a significant reduction in PIMs and new-onset potentially severe DDIs. CPSSs combining different prescribing quality measures should be considered as an important strategy for optimizing medication prescription for elderly patients.

Avaliação de interações medicamentosas potenciais em prescrições da atenção primária de Vitória da Conquista (BA), Brasil

As interações medicamentosas são fatores de risco para a ocorrência de reações adversas a medicamentos. Este estudo teve o objetivo de avaliar as interações medicamentosas potenciais em prescrições da atenção primária de Vitória da Conquista (BA), visando preencher a lacuna de conhecimento sobre essa temática no Brasil. Foram coletadas informações sobre diversas variáveis de prescrições oriundas da atenção primária e as interações medicamentosas avaliadas a partir dos bancos de dados do Medscape e Micromedex(r). Verificou-se ainda a frequência de polifarmácia e associação desta com a ocorrência de interações medicamentosas. Os resultados mostraram frequência de 48,9% de interações medicamentosas, 74,9% delas de gravidade moderada ou maior, e 8,6% de prescrições em polifarmácia que, em teste qui-quadrado, mostrou associação positiva com ocorrência de interações medicamentosas potenciais (p < 0,001). As prescrições oriundas da atenção primária de Vitória da Conquista (BA) apresentaram uma alta frequência de interações medicamentosas, porém faz-se necessária a análise de outros fatores de risco para ocorrência destas nesse nível de atenção à saúde.

Polypharmacy and risk of antiretroviral drug interactions among the aging HIV-infected population

BACKGROUND

Among aging HIV-infected adults, polypharmacy and its consequences have not been well-described.

OBJECTIVE

To characterize the extent of polypharmacy and the risk of antiretroviral (ARV) drug interactions among persons of different ages.

DESIGN AND PARTICIPANTS

Cross-sectional analysis among patients within the HIV Outpatient Study (HOPS) cohort who were prescribed ARVs during 2006-2010.

MAIN MEASURES

We used the University of Liverpool HIV drug interactions database to identify ARV/non-ARV interactions with potential for clinical significance.

KEY RESULTS

Of 3,810 patients analyzed (median age 46 years, 34 % ≥ 50 years old) at midpoint of observation, 1,494 (39 %) patients were prescribed ≥ 5 non-ARV medications: 706 (54 %) of 1,312 patients ≥ 50 years old compared with 788 (32 %) of 2,498 patients < 50 years. During the five-year period, the number of patients who were prescribed at least one ARV/non-ARV combination that was contraindicated or had moderate or high evidence of interaction was 267 (7 %) and 1,267 (33 %), respectively. Variables independently associated with having been prescribed a contraindicated ARV/non-ARV combination included older age (adjusted odds ratio [aOR] per 10 years of age 1.17, 95 % CI 1.01-1.35), anxiety (aOR 1.78, 95 % CI 1.32-2.40), dyslipidemia (aOR 1.96, 95 % CI 1.28-2.99), higher daily non-ARV medication burden (aOR 1.13, 95 % CI 1.10-1.17), and having been prescribed a protease inhibitor (aOR 2.10, 95 % CI 1.59-2.76). Compared with patients < 50 years, older patients were more likely to have been prescribed an ARV/non-ARV combination that was contraindicated (unadjusted OR 1.44, 95 % CI 1.14-1.82), or had moderate or high evidence of interaction (unadjusted OR 1.29, 95 % CI 1.15-1.44).

CONCLUSIONS

A substantial percentage of patients were prescribed at least one ARV/non-ARV combination that was contraindicated or had potential for a clinically significant interaction. As HIV-infected patients age and experience multiple comorbidities, systematic reviews of current medications by providers may reduce risk of such exposures.

Drug-drug interactions in a cohort of hospitalized elderly patients

PURPOSE

The aim of this study is to assess the prevalence of patients exposed to potentially severe drug-drug interactions (DDIs) at hospital admission and discharge and the related risk of in-hospital mortality and adverse clinical events, readmission, and all-cause mortality at 3 months.

METHODS

This cross-sectional, prospective study was held in 70 Italian internal medicine and geriatric wards. Potentially severe DDIs at hospital admission and discharge; risk of in-hospital mortality and of adverse clinical events, readmission, and all-cause mortality at 3-month follow-up.

RESULTS

Among 2712 patients aged 65 years or older recruited at hospital admission, 1642 (60.5%) were exposed to at least one potential DDI and 512 (18.9%) to at least one potentially severe DDI. Among 2314 patients discharged, 1598 (69.1%) were exposed to at least one potential DDI and 1561 (24.2%) to at least one potentially severe DDI. Multivariate analysis found a significant association with an increased risk of mortality at 3 months in patients exposed to at least two potentially severe DDIs (Odds ratio 2.62; 95% confidence interval, 1.00-6.68; p = 0.05). Adverse clinical events were potentially related to severe DDIs in two patients who died in the hospital, in five readmitted, and one who died at 3 months after discharge.

CONCLUSIONS

Hospitalization was associated with an increase in potentially severe DDIs. A significant association was found for mortality at 3 months after discharge in patients with at least two potentially severe DDIs. Careful monitoring for potentially severe DDIs, especially those created at discharge or recently generated, is important to minimize the risk of harm.

Potential drug-drug interactions in prescriptions to patients over 45 years of age in primary care, southern Brazil

BACKGROUND

Few cross-sectional studies involving adults and elderly patients with major DDIs have been conducted in the primary care setting. The study aimed to investigate the prevalence of potential drug-drug interactions (DDIs) in patients treated in primary care.

METHODOLOGY/PRINCIPAL FINDINGS

A cross-sectional study involving patients aged 45 years or older was conducted at 25 Basic Health Units in the city of Maringá (southern Brazil) from May to December 2010. The data were collected from prescriptions at the pharmacy of the health unit at the time of the delivery of medication to the patient. After delivery, the researcher checked the electronic medical records of the patient. A total of 827 patients were investigated (mean age: 64.1; mean number of medications: 4.4). DDIs were identified in the Micromedex® database. The prevalence of potential DDIs and major DDIs was 63.0% and 12.1%, respectively. In both the univariate and multivariate analyses, the number of drugs prescribed was significantly associated with potential DDIs, with an increasing risk from three to five drugs (OR = 4.74; 95% CI: 2.90-7.73) to six or more drugs (OR = 23.03; 95% CI: 10.42-50.91). Forty drugs accounted for 122 pairs of major DDIs, the most frequent of which involved simvastatin (23.8%), captopril/enalapril (16.4%) and fluoxetine (16.4%).

CONCLUSIONS/SIGNIFICANCE

This is the first large-scale study on primary care carried out in Latin America. Based on the findings, the estimated prevalence of potential DDIs was high, whereas clinically significant DDIs occurred in a smaller proportion. Exposing patients to a greater number of prescription drugs, especially three or more, proved to be a significant predictor of DDIs. Prescribers should be more aware of potential DDIs. Future studies should assess potential DDIs in primary care over a longer period of time.

Predictors of health related quality of life in older people with non-communicable diseases attending three primary care clinics in Malaysia

OBJECTIVES

To determine the health related quality of life and its predictive factors among older people with non-communicable diseases attending primary care clinics.

DESIGN

Cross-sectional study.

SETTING

Three public primary care clinics in a district in Selangor, Malaysia.

PARTICIPANTS

Registered patients aged 55 years and above.

MEASUREMENTS

A face-to-face interview was conducted using a validated questionnaire of Medical Outcome Study 36-item short form health survey (SF-36). The outcome measure was the health related quality of life (HRQoL) and other factors measured were socio demography, physical activity, social support (Duke-UNC Functional Social Support Questionnaire), and presence of non-communicable diseases.

RESULTS

A total of 347 participants had non-communicable diseases which included hypertension (41.8%), type 2 diabetes (33.7%), asthma (4.8%), hyperlipidaemia (1.7%), coronary heart disease (1.2%), and osteoarthritis (0.2%). Age ≥ 65 years old (OR =2.23; 95%CI=1.42, 3.50), single (OR=1.75; 95%CI=1.06,2.90), presence of co-morbid condition (OR=1.66; 95%CI=1.06, 2.61), and poorer social support (OR=2.11; 95%CI=1.27, 3.51; p=0.002) were significant predictors of poorer physical component of HRQoL . In predicting lower mental health component of HRQoL, the significant predictors were women (OR=2.28; 95%CI=1.44, 3.62), Indian ethnicity (OR=1.86; 95%CI=1.08, 3.21) and poorer social support (OR=2.71; 95%CI=1.63, 4.51). No interactions existed between these predictors.

CONCLUSION

Older people with non-communicable diseases were susceptible to lower health related quality of life. Increasing age, single, presence of co-morbid conditions, and poorer social support were predictors of lower physical health component of HRQoL. While the older women, Indian ethnicity and poorer social support reported lower mental health component of HRQoL.

Adverse drug reactions caused by drug-drug interactions reported to Croatian Agency for Medicinal Products and Medical Devices: a retrospective observational study

Aim

To analyze potential and actual drug-drug interactions reported to the Spontaneous Reporting Database of the Croatian Agency for Medicinal Products and Medical Devices (HALMED) and determine their incidence.

Methods

In this retrospective observational study performed from March 2005 to December 2008, we detected potential and actual drug-drug interactions using interaction programs and analyzed them.

Results

HALMED received 1209 reports involving at least two drugs. There were 468 (38.7%) reports on potential drug-drug interactions, 94 of which (7.8% of total reports) were actual drug-drug interactions. Among actual drug-drug interaction reports, the proportion of serious adverse drug reactions (53 out of 94) and the number of drugs (n = 4) was significantly higher (P < 0.001) than among the remaining reports (580 out of 1982; n = 2, respectively). Actual drug-drug interactions most frequently involved nervous system agents (34.0%), and interactions caused by antiplatelet, anticoagulant, and non-steroidal anti-inflammatory drugs were in most cases serious. In only 12 out of 94 reports, actual drug-drug interactions were recognized by the reporter.

Conclusion

The study confirmed that the Spontaneous Reporting Database was a valuable resource for detecting actual drug-drug interactions. Also, it identified drugs leading to serious adverse drug reactions and deaths, thus indicating the areas which should be in the focus of health care education.