Prevalence of potential drug interactions in an Iranian general hospital

Drug use survey to identify significant drug-drug interactions and assess clinical importance in the outpatient setting of a tertiary care hospital

OBJECTIVES

Drug-drug interactions (DDIs) are a common problem in pharmacotherapy, particularly in situations where multiple disorders must be treated at the same time. We conducted a drug use survey in the general medicine outpatient department of a tertiary care hospital with the objective of assessing the potential for DDI in individual prescriptions for adult patients.

MATERIALS AND METHODS

Drugs prescribed in the current physician-patient encounter were considered in conjunction with medicines already being received by the patient as well as those discontinued in the past 1 month. Free online DDI checkers (available at https://www.drugs.com/drug_interactions.html and https://reference.medscape.com/) were used to identify potential DDI and categorize them into mild, moderate, and severe categories. We did not consider food, alcohol, or smoking-related interactions.

RESULTS

A total of 153 prescriptions, having two or more drugs, were collected, and they accounted for 1052 prescribed drugs. Among them, 613 (58.27%) were prescribed in index visits, and the rest 438 (41.63%) were preexisting medication. The number of drugs prescribed in index visits ranged from 1 to 9 (mean ± standard deviation [SD] 4.0 ± 1.86; median 4). Potential DDIs were identified in 103 (67.32%) instances. The total number of interactions identified was 412. Of these, 19.66% had minor, 77.67% moderate, and 7.19% major clinical implications. Potential DDI count in each prescription was found from 0 to 13 in number (mean ± SD 2.7 ± 3.12; median 2.0). This number correlated strongly with the number of drugs being received by individual subjects (Rho 0.744; P < 0.001).

CONCLUSIONS

Potential DDIs are a reality in day to day prescribing practice. Substantial proportion of these DDIs may have significant clinical implications. Prescribers need to be sensitized to this issue. Combining human expertise with technological solutions such as automated drug interaction alerts can help rectify the situation. Similar surveys are needed on a periodic basis to improve medication safety for patients.

The Prevalence and Severity of Potential Drug-Drug Interactions in Internal Medicine Ward at Soba Teaching Hospital

Background

Multiple drug therapies are commonly used to achieve a desired therapeutic goal, especially in hospitalized patients. However, drug-drug interactions might occur and threaten the patients' safety.

Objective

This study aims to assess the prevalence and severity of potential drug-drug interactions (PDDIs) in the internal medicine ward at Soba Teaching Hospital.

Methods

A retrospective cross-sectional hospital-based study was carried out in the internal medicine ward at Soba Teaching Hospital from June 2021 to December 2021. The data was collected from patients' medical records. PDDIs were identified using Lexicomp® drug interaction software.

Results

A total of 377 patients were included in this study, and overall prevalence of PDDIs was 62.9%. We have identified 989 potential DDIs and 345 pairs of interacting drugs, the mean of the PDDIs per patient was 4.17 ± 4.079. Among 345 PDDIs most were of moderate interactions 70.1% (n=242) followed by Minor interactions 19.1% (n=66). The most common type of interaction was of category C representing 63.5% (n=219). A significant association was observed between the occurrence of PDDIs with patients' age, presence of chronic diseases, length of hospital stay, and number of medications received by the patients.

Conclusion

Drug-drug interactions were highly prevalent in the internal medicine ward. Therefore, certain attempts are required to increase the awareness of the physicians about these interactions and minimize their occurrence.

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.

Assessment of Potential Drug-Drug Interactions in Hospitalized Cardiac Patients of a Secondary Care Hospital in the United Arab Emirates

OBJECTIVE

To identify the types, severity, and documentation grades of potential drug-drug interactions (pDDIs) and to identify the predictors of pDDIs among hospitalized cardiac patients.

METHODS

This was a cross-sectional study. All the patients who were admitted for >24 h in a cardiology ward of a general hospital of the United Arab Emirates and prescribed with cardiac medications were included. The occurrence of any pDDI between cardiac medications and other coprescribed medications was identified using Micromedex database 2.0^® and graded and documented based on the severity and documentation.

FINDINGS

A total of 842 pDDIs were identified in 155 patients. The overall relevant frequency for the occurrence of pDDIs was found to be 87.74%. A total of 79 pairs of pDDIs were identified. Among identified pDDIs, 41.33% and 56.65% were major and moderate severity type, respectively, whereas 12.32% were excellent and 36.81% were good documentation grade. The majority of pDDIs were between aspirin-bisoprolol (11.64%). Patients taking more than seven drugs (odds ratio [OR] = 9.90; 95% confidence interval [CI]: 2.28-42.99), polypharmacy (OR = 3.86; 95% CI: 0.93-16.08), and number of medical conditions (OR 0.25; 95% CI: 0.09-0.68) were significant predictors of pDDIs.

CONCLUSION

The study fosters the importance of regular and close monitoring for pDDIs among cardiac patients. Thus, multicenter interventional studies are required to determine the exact nature and types of pDDIs in the local population.

Medication Interaction and Physicians' Compliance Assessment through Medication Reconciliation Forms in a University Affiliated Hospital

Medication interactions are associated with various unwanted adverse drug reactions. Medication Reconciliation involves a process in which a complete list of patient's previously prescribed medications are recorded and subsequently evaluated within the context of concomitantly prescribed medications and present medical condition during the hospitalization. Medical records of randomly selected 270 patients hospitalized in internal medicine, cardiovascular and infectious diseases wards were evaluated. Drug interactions were checked by LexiComp® database. Each interaction was assigned a risk rating of A, B, C, D, or X. The progression from A to X was based on increased urgency for responding to the data. Completed reconciliation forms were attached to patient charts for evaluation of physicians' compliance. Drug interactions were observed in 65.2% (176/270) of cases. The risk rating of interactions was categorized as C, D and X in 54.2%, 32.4%, and 13.4% of cases, respectively. There was a positive correlation between the number of prescribed medications and the rate of interactions (p-value < 0.001, Kendall's correlation coefficient = 0.487). Moreover, the length of hospitalization and the rate of drug interactions were significantly correlated (p-value < 0.001, Kendall's correlation coefficient = 0.350). Cardiovascular agents constituted the largest proportion of interactions (25%) followed by antibiotics (18%) and immunosuppressive agents (6%). In 59.6% of cases, no corrective action was taken by the physicians. Medication discrepancies occur commonly in hospital settings. Structured medication reconciliation may have a positive impact on prevention of medication errors.

Potential drug-drug interactions in inpatients treated at the Internal Medicine ward of Tikur Anbessa Specialized Hospital

PURPOSE

Although the concomitant use of multiple drugs often increases therapeutic effectiveness, certain combinations result in unwanted drug-drug interactions (DDIs). Most interactions go unnoticed by physicians due to the absence of new clinical signs and symptoms, and because they often produce a worsening of already existing symptoms. Quantification of the occurrence of the potential DDIs is essential to prevent the harmful effects associated with interactions. This study was launched to assess the prevalence of potential DDIs in the Internal Medicine ward of Tikur Anbessa Specialized Hospital, Addis Ababa, Ethiopia.

PATIENTS AND METHODS

Cross-sectional data were gathered from the medical charts of 252 randomly selected patients who were admitted to the Internal Medicine ward during August 23 to October 23, 2013, and exposed to at least two concomitant drugs. Potential DDIs were identified using Medscape Drug Interaction Checker. The data were analyzed using SPSS software. Logistic regression analysis was used to determine the presence of association between variables and p-value <0.05 was considered statistically significant.

RESULTS

At least one potential DDI was found in 78.2% of the patients. The mean number of potential interactions per patient was 3.7±3.4. Out of the 719 potential interactions identified, 49.8% were pharmacokinetic type, 44.6% were pharmacodynamic and the remaining 5.6% were unknown mechanisms. Major potential DDIs accounted for 13.1% of the whole interactions; 53.5% were moderate interactions; and the remaining 33.4% were minor interactions. Ceftriaxone, cimetidine and heparin were the three most involved drugs in major potential interactions. Prescription of five or more concomitant drugs was associated with high risk of encountering potential DDIs.

CONCLUSION

The findings of this study showed that the prevalence of potential DDIs among inpatients was high. Pharmacists should closely review drugs prescribed for patients and avoid dispensing combinations of drugs that may have serious DDIs.

Risk factors for potential drug-drug interactions in intensive care unit patients

PURPOSE

To determine risk factors for each severity-based category of potential drug-drug interactions (DDIs) encountered at intensive care unit (ICU) patients.

METHODS

This was a retrospective cohort analysis of patients treated at the ICU of the Clinical Center Kragujevac, a public tertiary care hospital in Kragujevac, Serbia. Three interaction checkers were used to reveal drug-drug interactions: Medscape, Epocrates and Micromedex.

RESULTS

The study included 201 patients, 66.19±16.11 years of age. Average number of DDIs per patient ranged from 10.49±8.80 (Micromedex) to 29.43±21.51 (Medscape). Antiarrhythmic or anticonvulsant drug prescription, Charlson Comorbidity Index, male sex, length of hospitalization, number of drugs or therapeutic groups prescribed and surgery increased the risk of DDIs in ICU patients, while presence of delirium or dementia and transfer from emergency department to ICU protected against.

CONCLUSIONS

The rate of the DDIs in ICU patients at a tertiary care hospital is high, and adversely influenced by number of drugs or drug groups prescribed per patient, antiarrhythmic or anticonvulsant drug prescription, comorbidities, length of hospitalization and surgery. On the other hand, presence of cognitive deficit and transfer from emergency department to ICU protect ICU patients from the DDIs.

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.

A study of medication errors in a tertiary care hospital

Objective:

To determine the nature and types of medication errors (MEs), to evaluate occurrence of drug-drug interactions (DDIs), and assess rationality of prescription orders in a tertiary care teaching hospital.

Materials and Methods:

A prospective, observational study was conducted in General Medicine and Pediatric ward of Civil Hospital, Ahmedabad during October 2012 to January 2014. MEs were categorized as prescription error, dispensing error, and administration error (AE). The case records and treatment charts were reviewed. The investigator also accompanied the staff nurse during the ward rounds and interviewed patients or care taker to gather information, if necessary. DDIs were assessed by Medscape Drug Interaction Checker software (version 4.4). Rationality of prescriptions was assessed using Phadke's criteria.

Results:

A total of 1109 patients (511 in Medicine and 598 in Pediatric ward) were included during the study period. Total number of MEs was 403 (36%) of which, 195 (38%) were in Medicine and 208 (35%) were in Pediatric wards. The most common ME was PEs 262 (65%) followed by AEs 126 (31%). A potential significant DDIs were observed in 191 (17%) and serious DDIs in 48 (4%) prescriptions. Majority of prescriptions were semirational 555 (53%) followed by irrational 317 (30%), while 170 (17%) prescriptions were rational.

Conclusion:

There is a need to establish ME reporting system to reduce its incidence and improve patient care and safety.

The prevalence of major potential drug-drug interactions at a University health centre pharmacy in Jamaica

OBJECTIVE

To identify major potential drug-drug interactions (DDIs) on prescriptions filled at the University Health Centre Pharmacy, Mona Campus, Jamaica.

METHODS

This investigation utilised a cross-sectional analysis on all prescriptions with more than one drug that were filled at the Health Centre Pharmacy between November 2012 and February 2013. Potential DDIs were identified using the online Drug Interactions Checker database of Drugs.com.

RESULTS

During the period of the study, a total of 2814 prescriptions were analysed for potential DDIs. The prevalence of potential DDIs found during the study period was 49.82%. Major potential DDIs accounted for 4.7 % of the total number of interactions detected, while moderate potential DDIs and minor potential DDIs were 80.8 % and 14.5 % respectively. The three most frequently occurring major potential DDIs were amlodipine and simvastatin (n=46), amiloride and losartan (n=27) and amiloride and lisinopril (n=16).

CONCLUSION

This study has highlighted the need for educational initiatives to ensure that physicians and pharmacists collaborate in an effort to minimise the risks to the patients. These interactions are avoidable for the most part, as the use of online tools can facilitate the selection of therapeutic alternatives or guide decisions for closer patient monitoring and thus reduce the risks of adverse events.

A study on drug-drug interactions through prescription analysis in a South Indian teaching hospital

OBJECTIVE

The objective of this study was to assess the drug-drug interactions (DDIs) through prescription analysis among the inpatients of a South Indian teaching hospital.

METHODS

The study was a prospective observational prescription analysis conducted for a period of 6 months, from October 2010 to March 2011. The prescriptions having two or more drugs and where a DDI was suspected were selected by the physician in charge of the ward. The drugs in the prescription were then entered into the drug interaction checker software. The DDIs were classified based on the mechanism of interactions, severity of interactions, relation to the number of drugs prescribed, and disease conditions were also determined.

RESULTS

A total of 204 prescriptions were analyzed, of which 186 prescriptions had 856 DDIs. Most of the DDIs were pharmacokinetic drug interactions (42%) followed by unknown mechanisms (34%) and pharmacodynamic mechanisms (24%). The study findings showed that the prescriptions for cardiovascular with respiratory disease conditions had the greatest number of drug interactions on average. A severity assessment showed that majority of the DDIs were moderate (70%) followed by minor (28%). The study results showed that as the number of drugs increases in a prescription, the number of DDIs also increases. The interventions determined showed that dosage adjustment (12%) was to be followed in most of the DDIs.

CONCLUSION

This study assists in understanding the factors associated with DDIs that can help in safe and effective use of drugs in the future.

Drug-drug interactions in inpatient and outpatient settings in Iran: a systematic review of the literature

Drug-drug interactions (DDIs) are an important type of adverse drug events. Yet overall incidence and pattern of DDIs in Iran has not been well documented and little information is available about the strategies that have been used for their prevention. The purpose of this study was to systematically review the literature on the incidence and pattern of DDIs in Iran as well as the used strategies for their prevention. PubMed, Scopus, electronic Persian databases, and Google Scholar were searched to identify published studies on DDIs in Iran. Additionally, the reference lists of all retrieved articles were reviewed to identify additional relevant articles. Eligible studies were those that analyzed original data on the incidence of DDIs in inpatient or outpatient settings in Iran. Articles about one specific DDI and drug interactions with herbs, diseases, and nutrients were excluded. The quality of included studies was assessed using quality assessment criteria. Database searches yielded 1053 potentially eligible citations. After removing duplicates, screening titles and abstracts, and reading full texts, 34 articles were found to be relevant. The quality assessment of the included studies showed a relatively poor quality. In terms of study setting, 18 and 16 studies have been conducted in inpatient and outpatient settings, respectively. All studies focused on potential DDIs while no study assessed actual DDIs. The median incidence of potential DDIs in outpatient settings was 8.5% per prescription while it was 19.2% in inpatient settings. The most indicated factor influencing DDIs incidence was patient age. The most involved drug classes in DDIs were beta blockers, angiotensin-converting-enzyme inhibitors (ACEIs), diuretic agents, and non-steroidal anti-inflammatory drugs (NSAIDs). Thirty-one studies were observational and three were experimental in which the strategies to reduce DDIs were applied. Although almost all studies concluded that the incidence of potential DDIs in Iran in both inpatient and outpatient settings was relatively high, there is still no evidence of the incidence of actual DDIs. More extensive research is needed to identify and minimize factors associated with incidence of DDIs, and to evaluate the effects of preventive interventions especially those that utilize information technology.