Potential drug-drug interactions in older adults: A population-based study

Clinical impact of medication review and deprescribing in older inpatients: A systematic review and meta-analysis

BACKGROUND

Polypharmacy is a primary risk factor for the prescription of potentially inappropriate medications (PIMs), drug-drug interactions (DDIs), and ultimately, adverse drug reactions (ADRs). Medication review and deprescribing represent effective strategies to simplify therapeutic regimens, minimize risks, and reduce PIM prescriptions. This systematic review and meta-analysis of experimental and observational studies aimed to evaluate the impact of different medication review and deprescribing interventions in hospitalized older patients.

METHODS

Experimental and observational prospective cohort studies evaluating the clinical effects of medication review and deprescribing strategies in older hospitalized patients were searched in the bibliographic databases, PubMed, Embase, and Scopus, from inception until January 8, 2024. A narrative synthesis of the results was provided, along with a meta-analysis of dichotomous data (i.e., re-hospitalizations and mortality).

RESULTS

Overall, 21 randomized controlled trials, 7 non-randomized interventional studies, and 2 prospective cohort studies were included in the systematic review. Of these, 14 (46.7%) assessed medication appropriateness as the primary outcome, while the remaining evaluated clinical outcomes (e.g., length of hospital stay, hospital readmissions, emergency department visits, and incidence of ADRs) and/or quality of life. The meta-analysis revealed a slight but statistically significant 8% reduction in hospital readmissions (HR: 0.92; 95% CI: 0.85-0.99) following medication review and deprescribing, but no significant impact on mortality (HR: 0.98; 95% CI: 0.96-1.00). Of the 30 included studies, 21 were considered at high risk of bias, mostly due to potential deviations from intended interventions and randomization processes. The remaining nine studies had "some concerns" (eight studies) or were considered at "low" risk of bias (one study).

CONCLUSION

Medication review and deprescribing are associated with potential benefits in reducing hospital readmission rates among hospitalized older patients, particularly through the reduction of PIM prescriptions. The integration of thorough medication review and deprescribing protocols in hospital settings may improve post-discharge outcomes and reduce overall healthcare costs.

High prevalence of potential psychotropic drugs interactions among Brazilian dental patients

OBJECTIVE

To determine the prevalence of potential drug-drug interactions involving psychotropics prescribed by dentists, and dispensed by the public healthcare system, as well as to describe the severity and level of evidence of those interactions in the state of Minas Gerais, Brazil.

MATERIALS AND METHODS

We conducted data analysis from pharmaceutical claims in which dental patients received systemic psychotropics in 2017. Data from the Pharmaceutical Management System provided the drug dispensing history of the patients, allowing the identification of those on concomitant medication use. The outcome was the occurrence of potential drug-drug interactions, which were detected according to IBM Micromedex®. Independent variables were the patient's sex, age, and the number of drugs used. Descriptive statistics was performed using SPSS v. 26.

RESULTS

Overall, 1480 individuals were prescribed psychotropic drugs. The prevalence of potential drug-drug interactions was 24.8% (n = 366). The total of 648 interactions was observed and, most of which were of major severity (n = 438, 67.6%). Most interactions occurred in female individuals (n = 235; 64.2%), with 46.0 (±17.3) years-old, concurrently taking 3.7 (±1.9) drugs.

CONCLUSION

A substantial proportion of dental patients presented potential drug-drug interactions, mostly of major severity, which might be life-threatening.

Potential Drug-Drug Interactions Among Hospitalised Elderly Patients in Northern Sri Lanka, A Lower Middle-Income Country: A Retrospective Analysis

BACKGROUND AND OBJECTIVES

Elderly individuals are more vulnerable to potential drug-drug interactions (pDDIs) as age-related physiological changes, polypharmacy and hospitalisations are known to increase the risk of pDDIs. The aims of this study were to assess the impact of hospitalisation and other associated factors on pDDIs in elderly patients, in a resource-limited setting.

METHODS

This is a retrospective analysis of data of elderly patients (aged ≥ 65 years) admitted to the medical units of Jaffna Teaching Hospital. Preadmission and post-admission data were collected from clinic and hospital records, respectively. The British National Formulary was used to identify and categorise pDDIs. Point prevalence of pDDIs in elderly patients and the total number of pDDIs before and after hospitalisation were estimated. Factors contributing to pDDIs were determined by univariate and multivariable logistic regression.

RESULTS

Two hundred and eighty-eight hospitalised elderly patients with a median age of 71 years (interquartile range 67-76 years) showed a significant increase in the prevalence of pDDIs post-admission compared with the preadmission values (77.1% vs 61.5%; p < 0.001) associated with an increase in total pDDIs (377 vs 488; p < 0.001) where the majority (> 75%) were potential pharmacodynamic interactions. An unadjusted analysis showed a significant association between pDDI and polypharmacy [taking five or more medications] (odds ratio [OR] = 14.17; 95% confidence interval [CI] 7.41-27.10), the presence of more than three underlying medical conditions (OR 4.14; 95% CI 1.70-10.06), ischaemic heart disease (OR 3.25; 95% CI 1.78-5.94) and asthma (OR 8.14; 95% CI 2.46-26.88). However, when adjusted for confounders only polypharmacy (OR 14.10; 95% CI 6.50-30.60) and the presence of underlying asthma (OR 11.61; 95% CI 2.82-47.85) were associated with pDDIs.

CONCLUSIONS

The prevalence of pDDIs among elderly patients was high and increased with hospital admissions. Polypharmacy and relevant comorbidities were contributory factors. Increased awareness of the potential for pDDIs through appropriate training and simple measures including a proper drug history, creating a bespoke pDDI list and frequent medication reviews by healthcare professionals would help to mitigate pDDIs in resource-limited and technology-limited settings.

Concurrent Use of Thyroid Hormone Therapy and Interfering Medications in Older US Veterans

CONTEXT

Thyroid hormone management in older adults is complicated by comorbidities and polypharmacy.

OBJECTIVE

Determine the prevalence of concurrent use of thyroid hormone and medications that can interfere with thyroid hormone metabolism (amiodarone, prednisone, prednisolone, carbamazepine, phenytoin, phenobarbital, tamoxifen), and patient characteristics associated with this practice.

DESIGN

Retrospective cohort study between 2004 and 2017 (median follow-up, 56 months).

SETTING

Veterans Health Administration Corporate Data Warehouse.

PARTICIPANTS

A total of 538 137 adults ≥ 65 years prescribed thyroid hormone therapy during the study period.

MAIN OUTCOME MEASURE

Concurrent use of thyroid hormone and medications interfering with thyroid hormone metabolism.

RESULTS

Overall, 168 878 (31.4%) patients were on at least 1 interfering medication while on thyroid hormone during the study period. In multivariable analyses, Black/African-American race (odds ratio [OR], 1.25; 95% CI, 1.21-1.28, compared with White), Hispanic ethnicity (OR, 1.12; 95% CI, 1.09-1.15, compared with non-Hispanic), female (OR, 1.11; 95% CI, 1.08-1.15, compared with male), and presence of comorbidities (eg, Charlson/Deyo Comorbidity Score ≥ 2; OR, 2.50; 95% CI, 2.45-2.54, compared with 0) were more likely to be associated with concurrent use of thyroid hormone and interfering medications. Older age (eg, ≥ 85 years; OR, 0.48; 95% CI, 0.47-0.48, compared with age 65-74 years) was less likely to be associated with this practice.

CONCLUSIONS AND RELEVANCE

Almost one-third of older adults on thyroid hormone were on medications known to interfere with thyroid hormone metabolism. Our findings highlight the complexity of thyroid hormone management in older adults, especially in women and minorities.

Time-Trends of Drug-Drug Interactions among Elderly Outpatients in the Piedmont Region (Italy): A Population-Based Study

Adverse drug reactions (ADRs) are a major health problem in the primary care setting, particularly among the elderly population. While the high frequency of ADRs in the elderly has several causes, a major and common determinant is polypharmacy, which can in turn increase the risk of drug-drug interactions (DDIs). In this paper, we analyzed the drugs prescriptions dispensed to elderly outpatients, to assess changes in the prevalence of selected DDIs in the period 2013−2019. Overall, about 15% of the patients aged >65 years were poly-treated. Among them, a decreasing trend in prevalence was observed for the majority of DDIs during the study period. This trend was particularly noticeable for DDIs involving fluoroquinolones and vitamin K antagonists, where a sharp reduction of over 40% was observed. On the opposite, a small increase in prevalence was observed for the association of antidiabetics and beta-blocking agents and for that of clopidogrel and PPIs. While the occurrence of most of the considered DDIs among poly-treated elderly decreased over time, the prevalence of some of them is still worrying. The complexity of the national drug formularies, as well as the increased number of prescribing actors that are involved, further urges the update of DDI lists to be used to monitor drug appropriateness and reduce avoidable ADRs.

Drug-Related Problems and Polypharmacy in Nursing Home Residents: A Cross-Sectional Study

At present, 19.2% of the Spanish population is aged 65 or older. Polypharmacy is a frequent condition among the elderly, especially in those living in nursing homes, which is associated with adverse outcomes, such as adverse drug events or drug-drug interactions. This study aimed to assess the pattern of polypharmacy in a nursing home in Leon, one of Spain's most ageing regions, and its relationship with different drug-related problems. A descriptive, observational, and cross-sectional study design was used; 222 residents were involved in this study. Data on drug use were collected from medical charts. Information was screened with the software CheckTheMeds, BOT PLUS and Drug-Reax. Residents were on a median of 7 medicines. Polypharmacy and inappropriate medications were present in 78.8% and 96.8% of residents, respectively. Drug-related problems were present in almost all the populations evaluated. Drug-drug interactions were very common in participants (81.1%), being severe/moderate in 24.7%. A high prevalence of polypharmacy and drug-related problems in the nursing home population assessed has been observed. A significantly higher risk of suffering drug-drug interactions was revealed for increasing polypharmacy and anticholinergic risk. A regular evaluation of drug prescribing in nursing home residents is necessary to minimize drug-related problems risk.

Prevalence and Factors Associated with Potential Drug-Drug Interactions in Older Community-Dwelling Adults: A Prospective Cohort Study

Background

Older patients are at increased risk of drug-drug interactions (DDIs) due to polypharmacy. Cardiovascular and central nervous system (CNS) drugs are commonly implicated in serious DDIs.

Objectives

This study aimed to determine the prevalence and factors associated with potential ‘severe’ cardiovascular and CNS DDIs among older (≥ 70 years) community-dwellers.

Methods

This was a prospective cohort study using linked data from a national pharmacy claims database and waves 1 and 2 of The Irish LongituDinal study on Ageing (TILDA). ‘Severe’ cardiovascular and CNS DDIs were identified using the British National Formulary 77 and Stockley’s Drug Interactions. The prevalence of ‘severe’ DDIs (any DDI vs. none) was calculated. Logistic regression was used to examine the association between sociodemographic, functional ability, and medication-related factors and the risk of DDI exposure between waves 1 and 2.

Results

A total of 1466 patients were included [mean age (standard deviation) = 78 (5.5) years; female n = 795, 54.2%]. In total, 332 community-dwellers aged ≥ 70 years [22.65%, 95% confidence interval (CI) 20.58–24.86] were potentially exposed to at least one ‘severe’ cardiovascular or CNS DDI, with more than half (54.82%) of this cohort dispensed the same DDI for a prolonged time (≥ 3 consecutive claims). Aspirin-warfarin was the most frequently dispensed (co-prescribed) DDI (n = 34, 10.24%, 95% CI 7.39–14.00), followed by atorvastatin-clarithromycin (n = 19, 5.72%, 95% CI 3.64–8.81). Polypharmacy [≥ 10 vs. < 5 drugs, odds ratio (OR) 13.40, 95% CI 8.22–21.85] and depression (depressed vs. not, OR 2.12, 95% CI 1.34–3.34) were significantly associated with these DDIs, after multivariable adjustment.

Conclusion

‘Severe’ cardiovascular and CNS DDIs are prevalent in older community-dwellers in Ireland, and those with polypharmacy and depression are at a significantly increased risk.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40266-021-00898-8.

REview of potentially inappropriate MEDIcation pr[e]scribing in Seniors (REMEDI[e]S): French implicit and explicit criteria

PURPOSE

To establish a consensus on both explicit and implicit criteria in order to identify potentially inappropriate prescribing (PIP) in French older people aged 75 years and over or 65 years and over with multimorbidity.

METHODS

Fifteen experts in geriatrics, general practice, pharmacy, and clinical pharmacology were involved in a two-round Delphi survey to assess preliminary explicit and implicit criteria based on an extensive literature review and up-to-date evidence data. Experts were asked to rate their level of agreement using a 5-level Likert scale for inclusion of criteria and also for rationale and therapeutic alternatives. A consensus was considered as reached if at least 75% of the experts rated criteria as "strongly agreed" or "agreed."

RESULTS

The new tool included a seven-step algorithm (implicit criteria) encompassing the three main domains that define PIP (i.e. overprescribing, underprescribing, and misprescribing) and 104 explicit criteria. Explicit criteria were divided into 6 tables related to inappropriate drug duplications (n = 7 criteria), omissions of medications and/or medication associations (n = 16), medications with an unfavourable benefit/risk ratio and/or a questionable efficacy (n = 39), medications with an unsuitable dose (n = 4) or duration (n = 6), drug-disease (n = 13), and drug-drug interactions (n = 19).

CONCLUSION

The REMEDI[e]S tool (REview of potentially inappropriate MEDIcation pr[e]scribing in Seniors) is an original mixed tool, adapted to French medical practices, aimed at preventing PIP both at the individual level in clinical practice and the population level in large-scale studies. Therefore, its use could contribute to an improvement in healthcare professionals' prescribing practices and safer care in older adults.

An International Consensus List of Potentially Clinically Significant Drug-Drug Interactions in Older People

OBJECTIVES

We aimed to establish an explicit list of potentially clinically significant drug-drug interactions (DDIs) in people aged ≥65 years.

DESIGN

A preliminary list of potentially clinically significant DDIs was compiled, based on 154 DDIs identified from literature review. Subsequently, a 2-round online Delphi survey was undertaken with a multidisciplinary expert panel. A consensus meeting and a final round were conducted to validate the final DDI list and the scope of information provided.

SETTING AND PARTICIPANTS

Twenty nine experts, including geriatricians and clinical pharmacists from 8 European countries.

MEASURES

For each DDI, in the first 2 rounds, experts were asked to score the severity of potential harm on a 5-point Likert-type scale. DDIs were directly included on the final list if the median score was 4 (major) or 5 (catastrophic). DDIs with a median score of 3 (moderate) were discussed at a consensus meeting and included if ≥75% of participants voted for inclusion in the final round.

RESULTS

Consensus was achieved on 66 potentially clinically significant DDIs (28 had a median score of 4/5 and 48 of 3 in the Delphi survey). Most concerned cardiovascular, antithrombotic, and central nervous system drugs. The final list includes information on the mechanism of interaction, harm, and management. Treatment modification is recommended for three-quarters of DDIs.

CONCLUSION AND IMPLICATIONS

We validated a list of potentially clinically significant DDIs in older people, which can be used in clinical practice and education to support identification and management of DDIs or to assess prevalence in epidemiologic and intervention studies.

Polypharmacy and Potential Drug-Drug Interactions in Home-Dwelling Older People - A Cross-Sectional Study

Background

Risks associated with polypharmacy and drug-drug interactions represent a challenge in drug treatment, especially in older adults. The aim of the present study was to assess the use of prescription and non-prescription drugs and the frequency of potential drug-drug interactions in home-dwelling older individuals.

Methods

A cross-sectional study design was applied. Data were collected during preventive home visits among individuals aged ≥75 in three separate communities of Western Norway. A questionnaire, which was filled out by the individual, their next-of-kin, and the nurse performing the home visit was used for the collection of demographic and clinical data (age, sex, medication use, diagnoses, need of assistance with drug administration). Potential drug-drug interactions were identified electronically by IBM Micromedex Drug Interaction Checking. Point prevalence of potential drug-drug interactions and polypharmacy (≥5 drugs) were calculated. Binary logistic regression analyses were performed to assess factors potentially associated with polypharmacy or potential drug-drug interactions.

Results

Among the 233 individuals (mean age 78±3 years, 46% male) included in the study, 43% used ≥5 drugs, 3.4% ≥10 drugs, while 4.3% used no drugs. In 54% of the 197 individuals using two or more drugs, at least one potential drug-drug interaction was detected. Low-dose aspirin and simvastatin were most frequently involved in potential drug-drug interactions. In total, 25% of the individuals reported current use of drugs sold over the counter of which more than 95% were analgesic drugs. Potential drug-drug interactions involving ibuprofen were identified in nine of 11 (82%) individuals using over-the-counter ibuprofen.

Conclusion

The study revealed a high prevalence of polypharmacy and potential drug-drug interactions with both prescription and non-prescription drugs in older home-dwelling individuals. Close monitoring of the patients at risk of drug-drug interactions, and increased awareness of the potential of over-the-counter drugs to cause drug-drug interactions, is needed.

Potential herb-drug interactions in community-dwelling older adults in China: the Shanghai Aging Study

BACKGROUND

Potential herb-drug interactions (pHDIs) often go unrecognized, and little is known about the prevalence of pHDIs in older adults.

AIMS

This study aimed to investigate the prevalence of pHDIs in community-dwelling older adults in Shanghai and identify patterns and factors associated with pHDIs.

METHODS

Baseline data from the Shanghai Aging Study, which was designed to establish a prospective community-based cohort of older adults in Shanghai, were analyzed regarding pHDIs with Lexi-Interact Online software.

RESULTS

Among 1227 participants who used any combination of drug-herb or herb-herb, 43.3% were exposed to at least one pHDI. A total of 1641 different pHDIs were identified among the study samples. Only seven (0.4%) pHDIs were rated as risk category X, indicating that the combinations were contraindicated and should be avoided. Worryingly, 876 (53.4%) pHDIs were rated as risk category D, indicating that significant interactions may occur and therapeutic modification should be considered. Of particular concern is that 99.8% of pHDIs in risk category D involve herbs with anticoagulant/antiplatelet properties. Individuals with stroke (odds ratio [OR] 2.02), hyperlipidemia (OR 1.51) or heart diseases (OR 1.42) and the number of herbs (2.66), number of drugs (OR 1.21), and age (OR 1.02) were significantly associated with the risk of pHDIs.

CONCLUSION

43.3% of community-dwelling older adults who used any combination of drug-herb or herb-herb was exposed to pHDIs, and more than half of pHDIs were related to herbs with anticoagulant/antiplatelet properties. Awareness of the patterns and high-risk groups of these pHDIs may contribute to increased patient safety.

[Potential drug interactions in adults and the elderly in primary health care]

The objective of the present study was to characterize the potential drug interactions (PDI), estimating the factors associated to their occurrence in adults and the elderly assisted by the Programa Médico de Família de Niterói, Rio de Janeiro. This is a sub-study of STUDY DIGITALIS, which included individuals enrolled in the Niteroi Family Medical Program (45-99 years). In this study, 341 individuals with a prescription of two or more drugs were analyzed. The classification of PDI followed MICROMEDEX. There were 113 different interactions. Of the total number of individuals, 63.6% had at least one PDI. The variables with higher probability of PDI were: lower level of schooling; income less than R$800.00; absence of health plan; previous diagnosis of hypertension and diabetes; use of 5 or more medications prescribed. After adjustment, the variables previous diagnosis of hypertension and diabetes and use of 5 or more prescription drugs remained statistically significant. Careful management of primary care treatment with monitoring is important in patients with PDI, especially in patients who are more susceptible.

Vaccines Safety in Children and in General Population: A Pharmacovigilance Study on Adverse Events Following Anti-Infective Vaccination in Italy

Background: The concern for adverse events following immunization (AEFI) and anti-vaccination movements that lacked scientific evidence-based supports may reduce vaccine uptake in the general population. Thus, the aims of the present study were to characterize AEFI in general population (all age groups), in terms of frequency, preventability, and seriousness and to define predictors of their seriousness in children.

Methods: A retrospective study was performed on suspected AEFI reports for children and adults who received any form of vaccinations, collected in Tuscany, Italy, between 1 January and 31 December 2017. Patients’ characteristics, suspected vaccines, and AEFI description were collected. Causality and preventability were assessed using WHO and Schumock and Thornton algorithms, respectively. Logistic regression was used to estimate the reporting odds ratios of potential predictors of AEFI seriousness in children.

Results: A total of 223 suspected AEFI reports were collected, and the majority of them were defined as non-serious (76.7%). Reports were mostly related to one vaccine, and to a median of two to five strains/toxoids. The total number of simultaneously administered strains/toxoids and the presence of allergens did not correlate with AEFI seriousness. Considering vaccines with a high number of administered doses (≥60,000 doses), the rates estimated for serious AEFI reports were always very low, ranging between 0.01 and 0.2/1,000 doses. Twenty-four vaccines (8,993 doses) were not related to any AEFI.

Conclusion: Results of present study showed that AEFI were very rare; the vast majority of them was non-serious and, despite the claims of anti-vaccination movements, the simultaneous administration of vaccines was safe and did not influence the risk of reporting a serious AEFI, particularly in children.

Are patients with a nasally placed feeding tube at risk of potential drug-drug interactions? A multicentre cross-sectional study

Aims

The primary aims were to determine the rate of potential drug-drug interactions (pDDIs) in patients with nasally placed feeding tubes (NPFT) and the factors significantly associated with pDDIs. The secondary aim was to assess the change in pDDIs for patients between admission and discharge.

Material and methods

This multicentre study applied a cross-sectional design and was conducted in six Brazilian hospitals, from October 2016 to July 2018. Data from patients with NPFT were collected through electronic forms. All regular medications prescribed were recorded. Medications were classified according to the World Health Organization (WHO) Anatomical Therapeutic Chemical code. Drug-drug interaction screening software was used to screen patients’ medications for pDDIs. Negative binomial regression was used to account for the over dispersed nature of the pDDI count. Since the number of pDDIs was closely related to the number of prescribed medications, we modelled the rate of pDDIs with the count of pDDIs as the numerator and the number of prescribed medications as the denominator; six variables were considered for inclusion: time (admission or discharge), patient age, patient gender, age-adjusted Charlson Comorbidity Index (CCI) score, type of prescription (electronic or handwritten) and patient care complexity. To account for correlation within the two time points (admission and discharge) for each patient a generalised estimating equations approach was used to adjust the standard error estimates. To test the change in pDDI rate between admission and discharge a full model of six variables was fitted to generate an adjusted estimate.

Results

In this study, 327 patients were included. At least one pDDI was found in more than 91% of patients on admission and discharge and most of these pDDIs were classified as major severity. Three factors were significantly associated with the rate of pDDIs per medication: patient age, patient care complexity and prescription type (handwritten vs electronic). There was no evidence of a difference in pDDI rate between admission and discharge.

Conclusion

Patients with a NPFT are at high risk of pDDIs. Drug interaction screening tools and computerized clinical decision support systems could be effective risk mitigation strategies for this patient group.

Characterization of drug-drug interactions in patients whose substance intake was objectively identified by detection in urine

BACKGROUND

Identification of drug-drug interactions (DDIs) typically relies on patient medication lists which are prone to inaccuracies. This study describes use of a mass spectrometry test to detect recently ingested substances in urine with subsequent identification of DDIs.

RESEARCH DESIGN AND METHODS

This was a retrospective analysis of the prevalence of DDIs identified in patients with chronic pain, addiction and/or behavioral health conditions in the U.S. Relationships between patient demographics, polypharmacy and the occurrence of DDIs were also described.

RESULTS

Of 15,004 patients, 2964 (20%) had a DDI identified. There was a positive association between the number of substances detected in urine and the number of interactions identified (r = 0.5033, p-value = 0.0001). Of patients with polypharmacy, 15.6% had contraindicated or severe interactions identified compared to only 3.2% of those without polypharmacy. For polypharmacy patients, the youngest population studied had a much higher likelihood of having one or more DDIs identified compared to the other age groups (p-value = 0.0002).

CONCLUSIONS

By utilizing a mass spectrometry test to objectively detect recently ingested substances followed by identification of DDIs, healthcare providers may be able to better characterize the true incidence of DDIs. Study findings may not be generalizable to healthcare populations outside of pain management, addiction treatment, and behavioral health.

Characterization of serious adverse drug reactions as cause of emergency department visit in children: a 5-years active pharmacovigilance study

Background

To describe frequency, preventability and seriousness of adverse drug reactions (ADRs) in children as cause of emergency department (ED) admission and to evaluate the association between specific factors and the reporting of ADRs.

Methods

A retrospective analysis based on reports of suspected ADRs collected between January 1st, 2012 and December 31st, 2016 in the ED of Meyer Children’s Hospital (Italy). Demographics, clinical status, suspected drugs, ADR description, and its degree of seriousness were collected. Logistic regression was used to estimate the reporting odds ratios (RORs) with 95% confidence intervals (CIs) of potential predictors of ADR seriousness.

Results

Within 5 years, we observed 834 ADRs (1100 drug-ADR pairs), of whom 239 were serious; of them, 224 led to hospitalization. Patients were mostly treated with one drug. Among patients treated with more than one drug, 78 ADRs presented a potential interaction. The most frequently reported ADRs involved gastrointestinal system. The most frequently reported medication class was antinfectives. Risk of serious ADR was significantly lower in children and infants compared to adolescents (ROR 0.41 [95% CI: 0.27–0.61] and 0.47 [0.32–0.71], respectively), and it was significantly increased in subjects exposed to more than one drug (ROR 1.87 [1.33–2.62] and 3.01 [2.07–4.37] for subjects exposed to 2 and 3 or more drugs, respectively). Gender, interactions and off-label drug use did not influence the risk of serious ADRs.

Conclusion

Active surveillance in pharmacovigilance might represent the best strategy to estimate and characterize the clinical burden of ADRs in children.

Electronic supplementary material

The online version of this article (10.1186/s40360-018-0207-4) contains supplementary material, which is available to authorized users.

Statin drug interactions and related adverse reactions: an update

INTRODUCTION

Statins reduce the risk of cardiovascular morbidity and mortality in patients with or at risk for cardiovascular disease and their use is expanding, especially in elderly. Statins are prescribed on a long-term basis and may undergo drug-drug interactions (DDIs) with other drugs. Statins have different safety and tolerability, and this might affect the possibility of DDIs with other cardiovascular drugs, increasing the risk of statin-associated myopathy and hepatotoxicity. Polypharmacy and pharmacogenetic variability are potential causes of statin DDIs. Thus, the safety and adverse effects of statins, particularly in patients receiving multiple medications at risk of DDIs, are a matter of special concern.

AREAS COVERED

The purpose of this manuscript is to give an update on the potential statin DDIs and related adverse drug reactions (myopathy and hepatotoxicity), with special considerations on polypharmacy in elderly population, HIV patients, cardiovascular drugs and liver toxicities. The potential DDIs among statins and monoclonal antibodies including the recently approved PCSK9 inhibitors are also extensively discussed in the present review.

EXPERT OPINION

A better understanding of the incidence and clinical significance of statin DDIs will help physicians in fine-tuning the lipid-lowering therapeutic interventions thus providing their patients with an evidence-based, safe and cost-effective clinical support.