Frequency and severity of potential drug interactions in a cohort of HIV-infected patients Identified through a Multidisciplinary team

Influence of the Type of Antiretroviral Treatment on the Time to Reach High Pharmacotherapy Complexity in People Living With HIV

BACKGROUND

The introduction of antiretroviral therapy (ARV) has significantly improved the survival of people living with HIV (PLWH), increasing the proportion of individuals over 50 years old. This aging trend poses challenges, such as the development of age-related comorbidities and a higher prevalence of polypharmacy. The pharmacotherapeutic complexity, assessed using the Medication Regimen Complexity Index (MRCI), is crucial for identifying and optimizing treatment, especially in elderly and polymedicated patients.

OBJECTIVE

The main objective was to assess the association between different ARV regimens and the time required to reach a high level of pharmacotherapeutic complexity in PLWH.

METHODS

A single-center observational analytical research study was conducted, including adult PLWH on active ARV from January 2010 to December 2021 with follow-up until December 2023. An analysis of the time to reach MRCI ≥11.25 was performed, followed by a Cox regression model to determine the influence of ARV on high MRCI.

RESULTS

A total of 789 PLWH were included, median age of 52 years (interquartile range: 45-58). Overall, 195 patients had an MRCI value ≥11.25 with a mean time to reach it of 181.86 months (95% confidence interval [CI]: 176.24 to 187.49). Significant differences were observed in sex, advanced age, AIDS stage, presence of comorbidities, polypharmacy, and ARV-related variables. A multivariate Cox proportional hazards model showed an association between integrase inhibitor (INSTI)-containing regimens (hazard ratio [HR]: 1.83; 95% CI: 1.08 to 3.10) and non-nucleoside reverse transcriptase inhibitor (NNRTI)-based regimens (HR: 0.72; 95% CI: 0.52 to 0.98) with the time to reach high MRCI.

CONCLUSIONS AND RELEVANCE

In summary, NNRTI-based regimens were associated with a lower likelihood of developing high MRCI compared to INSTI-based regimens, which was associated with a higher likelihood. These conclusions are based on a profile of PLWH that included advanced age and a high prevalence of comorbidities and polypharmacy. Identifying high MRCI may help us implement pharmacotherapeutic optimization strategies to improve health outcomes.

Primary care electronic medication record discrepancies in patients starting treatment at a hospital-based ambulatory care pharmacy and impact on prevalence of potential drug-drug interactions

OBJECTIVE

Our objective was to evaluate the prevalence of discrepancies between primary care electronic medication records (EMR) and patient reported medication (PRM) in ambulatory patients starting a hospital dispensing treatment (HDT) at a hospital-based ambulatory care pharmacy (HACPh). Our secondary aims were to analyse factors associated with the presence of discrepancies and their impact on the prevalence of potential drug-drug interactions (DDIs) with the HDT.

METHODS

Retrospective study including 230 patients starting a HDT at the HACPh. Pharmacists interviewed patients and PRM was compared with EMR. Discrepancies were classified as omissions (medication in the PRM not present in the EMR) and commissions (medication active in the EMR that the patients were not taking). Potential DDIs with the HDT were screened, and univariate and multivariate analyses were performed to detect factors associated with the presence of discrepancies.

RESULTS

We identified 221 discrepancies in 116 (50.4%) patients. Being visited by three or more medical specialties (OR 1.93, 95% CI 1.11 to 3.37) and attending private healthcare (OR 4.36, 95% CI 1.14 to 16.72) in the 12 months before the study inclusion were the factors independently associated with the presence of discrepancies. Among patients with commissions (n=91), 15.4% had a potential DDI between the HDT and one medication from the EMR that they were not taking at that moment. Among patients with omissions (n=45), 11.1% had a potential DDI between the HDT and a medication in the PRM not present in the EMR.

CONCLUSIONS

About 40% of patients had one or more medications in the EMR which they were not taking and one fifth used medications that were not listed in the EMR. EMR should not be used as the only source of information when screening for DDIs, especially in patients followed by different medical specialties or combining private and public healthcare.

Prevalence of Potentially Clinically Significant Drug-Drug Interactions With Antiretrovirals Against HIV Over Three Decades: A Systematic Review of the Literature

BACKGROUND

Contemporary first-line antiretrovirals have considerably reduced liability for clinically significant drug-drug interactions (DDI). This systematic review evaluates the prevalence of DDI among people receiving antiretrovirals across 3 decades.

METHODS

We searched 3 databases for studies reporting the prevalence of clinically significant DDIs in patients receiving antiretrovirals published between January 1987 and July 2022. Clinically significant DDIs were graded by severity. All data extractions were undertaken by 2 independent reviewers, adjudicated by a third.

RESULTS

Of 21,665 records returned, 13,474 were duplicates. After screening the remaining 13,596 abstracts against inclusion criteria, 122 articles were included for full-text analysis, from which a final list of 34 articles were included for data synthesis. The proportion of patients experiencing a clinically significant DDI did not change over time (P = 0.072). The most frequently reported classes of antiretrovirals involved in DDIs were protease inhibitors and non-nucleoside reverse transcriptase inhibitors; of note, integrase use in the most recent studies was highly variable and ranged between 0% and 89%.

CONCLUSIONS

The absolute risk of DDIs has not decreased over the period covered. This is likely related to continued use of older regimens and an ageing cohort of patients. A greater reduction in DDI prevalence can be anticipated with broader uptake of regimens containing unboosted integrase inhibitors or non-nucleoside reverse transcriptase inhibitors.

Perceptions Towards HCV Treatment with Direct Acting Antivirals (DAAs): A Qualitative Analysis with Persons with HIV/HCV Co-infection Who Delay or Refuse Treatment

In the United States, approximately 25% of people with HIV (PWH) are co-infected with hepatitis C (HCV). Since 2014, highly effective and well-tolerated direct-acting antivirals (DAAs) have revolutionized HCV treatment. Uptake of DAAs by people with HIV/HCV co-infection has improved but remains suboptimal due to system, provider, and patient-level barriers. To explore patient-level issues by better understanding their attitudes towards DAA treatment, we conducted qualitative interviews with 21 persons with HIV/HCV co-infection who did not consent to DAA treatment or delayed treatment for at least 1 year after diagnosis. We found PWH perceived DAA treatment barriers and facilitators on multiple levels of the social-ecological environment: the individual (HCV disease and treatment literacy), interpersonal (peer influence), institutional (media and healthcare provider relationship), and structural levels (treatment cost and adherence support). Recommendations to improve DAA treatment uptake include HCV-treatment adherence support, HCV disease and treatment literacy training (particularly for substance use and DAA treatment interactions), and encouraging PWH who have successfully completed DAA treatment to speak with their peers.

Early Antiretroviral Therapy in AIDS Patients Presenting With Toxoplasma gondii Encephalitis Is Associated With More Sequelae but Not Increased Mortality

Background

Evidence on the optimal time to initiate antiretroviral therapy (ART) in the presence of toxoplasmic encephalitis (TE) is scarce. We compared the impact of early vs. delayed ART initiation on mortality and neurologic complications at discharge in a Brazilian population co-infected with HIV and TE.

Methods

We retrospectively evaluated data from 9 years of hospitalizations at a referral center in Manaus, Amazonas. All ART-naïve hospitalized patients were divided into early initiation treatment (EIT) (0-4 weeks) and delayed initiation treatment (DIT) (>4 weeks). The groups were compared using chi-square test and mortality at 16 weeks.

Results

Four hundred sixty nine patients were included, of whom 357 (76.1%) belonged to the EIT group. The median CD4⁺ lymphocyte count and CD4⁺/CD8⁺ ratio were 53 cells/mm³ and 0.09, respectively. Mortality rate and presence of sequelae were 4.9% (n = 23) and 41.6% (n = 195), respectively. Mortality was similar between groups (p = 0.18), although the EIT group had the highest prevalence of sequelae at discharge (p = 0.04). The hazard ratio for death at 16 weeks with DIT was 2.3 (p = 0.18). The necessity for intensive care unit admission, mechanical ventilation, and cardiopulmonary resuscitation were similar between groups.

Conclusion

In patients with AIDS and TE, early ART initiation might have a detrimental influence on the occurrence of sequelae.

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.

Redefining therapeutic success in HIV patients: an expert view

Thanks to advances in the field over the years, HIV/AIDS has now become a manageable chronic condition. Nevertheless, a new set of HIV-associated complications has emerged, related in part to the accelerated ageing observed in people living with HIV/AIDS, the cumulative toxicities from exposure to antiretroviral drugs over decades and emerging comorbidities. As a result, HIV/AIDS can still have a negative impact on patients' quality of life (QoL). In this scenario, it is reasonable to believe that the concept of therapeutic success, traditionally associated with CD4 cell count restoration and HIV RNA plasma viral load suppression and the absence of drug resistances, needs to be redefined to include other factors that reach beyond antiretroviral efficacy. With this in mind, a group of experts initiated and coordinated the RET Project, and this group, using the available evidence and their clinical experience in the field, has proposed new criteria to redefine treatment success in HIV, arranged into five main concepts: rapid initiation, efficacy, simplicity, safety, and QoL. An extensive review of the literature was performed for each category, and results were discussed by a total of 32 clinicians with experience in HIV/AIDS (4 coordinators + 28 additional experts). This article summarizes the conclusions of these experts and presents the most updated overview on the five topics, along with a discussion of the experts' main concerns, conclusions and/or recommendations on the most controversial issues.

Beneficial and Adverse Effects of cART Affect Neurocognitive Function in HIV-1 Infection: Balancing Viral Suppression against Neuronal Stress and Injury

HIV-associated neurocognitive disorders (HAND) persist despite the successful introduction of combination antiretroviral therapy (cART). While insufficient concentration of certain antiretrovirals (ARV) may lead to incomplete viral suppression in the brain, many ARVs are found to cause neuropsychiatric adverse effects, indicating their penetration into the central nervous system (CNS). Several lines of evidence suggest shared critical roles of oxidative and endoplasmic reticulum stress, compromised neuronal energy homeostasis, and autophagy in the promotion of neuronal dysfunction associated with both HIV-1 infection and long-term cART or ARV use. As the lifespans of HIV patients are increased, unique challenges have surfaced. Longer lives convey prolonged exposure of the CNS to viral toxins, neurotoxic ARVs, polypharmacy with prescribed or illicit drug use, and age-related diseases. All of these factors can contribute to increased risks for the development of neuropsychiatric conditions and cognitive impairment, which can significantly impact patient well-being, cART adherence, and overall health outcome. Strategies to increase the penetration of cART into the brain to lower viral toxicity may detrimentally increase ARV neurotoxicity and neuropsychiatric adverse effects. As clinicians attempt to control peripheral viremia in an aging population of HIV-infected patients, they must navigate an increasingly complex myriad of comorbidities, pharmacogenetics, drug-drug interactions, and psychiatric and cognitive dysfunction. Here we review in comparison to the neuropathological effects of HIV-1 the available information on neuropsychiatric adverse effects and neurotoxicity of clinically used ARV and cART. It appears altogether that future cART aiming at controlling HIV-1 in the CNS and preventing HAND will require an intricate balancing act of suppressing viral replication while minimizing neurotoxicity, impairment of neurocognition, and neuropsychiatric adverse effects. Graphical abstract Schematic summary of the effects exerted on the brain and neurocognitive function by HIV-1 infection, comorbidities, psychostimulatory, illicit drugs, therapeutic drugs, such as antiretrovirals, the resulting polypharmacy and aging, as well as the potential interactions of all these factors.

Co-medications and Drug-Drug Interactions in People Living with HIV in Turkey in the Era of Integrase Inhibitors

BACKGROUND

Long life expectancy in people living with human immunodeficiency virus (PLWH) caused an increase in comorbidities and co-medications. We aimed to analyse comedications and drug-drug interactions (DDIs) in antiretroviral therapy (ART)-naive PLWH in the era of integrase inhibitors.

METHODS

A retrospective observational study was conducted between January 2016-August 2019. Patients' characteristics and chronic co-medications were recorded. The University of Liverpool HIV drug interaction database was used for DDIs.

RESULTS

Among 745 patients, the chronic co-medication rate was 30.9%. Older age (p<0.001, OR:6.66, 95% CI: 3.86-11.49) and female gender (p=002, OR:2.25, 95%:1.14-4.44) were independently associated with co-medication. Cardiovascular system (CVS) and central nervous system (CNS) drugs were the most common co-medications. Older age patients (p<0.001, OR:12.04, 95% CI:4.63-36.71), having heterosexual (HS) contact (p=0.003, OR:3.8, 95% CI:1.57-9.22) were independently associated with CVS drugs use, while being men who have sex with men (MSM) (p=0.03, OR:2.59, 95% CI:1.11-6.03) were associated with CNS drugs use. DDIs were seen in 37.4% of patients with co-medications. Antidiabetics (23.3%), CNS (22.1%) and CVS drugs (19.8%) most commonly had DDIs. Contraindication was most commonly seen between inhaled corticosteroids and elvitegravir/cobicistat. A number of non-ART drugs, elvitegravir/cobicistat, antidiabetics, vitamins were independently associated with the presence of DDIs.

CONCLUSION

Results suggested the need for attention about co-medication in PLWH regardless of whether they are young or older. CNS drugs should be questioned more detailed in MSM, as well as CVS drugs in older HS patients. Elvitegravir/cobicistat is significantly associated with DDIs and switching to an unboosted INSTI should be considered in patients with multiple comorbidities.

Evolution of Drug Interactions With Antiretroviral Medication in People With HIV

Background

Polypharmacy and drug interactions are important issues for HIV-infected individuals. The number and nature of those interactions are continuously evolving with the use of new antiretroviral drugs and the aging of HIV-infected individuals. We aimed to analyze this evolution over time.

Methods

This retrospective cohort study was conducted in the University Hospital of Liège (Belgium). Treatments of HIV-infected outpatients attending Liège University Hospital were collected and analyzed in 2012 and 2016. The University of Liverpool HIV drug interactions database was used to determine drug interactions.

Results

We included 1038 patients in 2016, of whom 78% had 1 comedication. Polypharmacy was seen in 20% of the cohort. Four percent of the patients presented red flag interactions, and 38% had orange flag interactions. Nonantiretroviral (non-ARV) therapeutic classes involved in drug interactions were mostly cardiovascular and central nervous system drugs. They were followed by hormone drugs and dietary supplements for orange flag interactions. Two factors significantly contributed to both red and orange flag interactions: the number of non-ARV comedications and protease inhibitor–based ARV regimens. The proportion of patients with red or orange flag interactions remained stable from 2012 to 2016.

Conclusions

This study highlights the persistence of an alarming number of contraindicated drug interactions and a high prevalence of potential drug interactions over time. Identification, prevention, and management of drug interactions remain a key priority in HIV care.

Assessment of drug-drug interaction in an elderly human immunodeficiency virus population: Comparison of 3 expert databases

AIMS

Polypharmacy increase the risk of drug-drug interactions (DDIs) in the elderly population living with human immunodeficiency virus (HIV). Several expert databases can be used to evaluate DDIs. The aim of the study was to describe actual DDIs between antiretroviral drugs and comedications in an elderly population and to compare grading of the DDIs in 3 databases.

METHODS

All treatments of HIV-infected subjects aged 65 years and older were collected in 6 French HIV centres. Summary of Product Characteristic (SPC), French DDI Thesaurus (THES), and Liverpool HIV DDI website (LIV) were used to define each DDI and specific grade. DDIs were classified in yellow flag interaction (undefined grade in SPC and THES or potential weak interaction in LIV), amber flag interaction (to be considered/precaution of use in SPC and THES and potential interaction in LIV) and red flag interaction (not recommended/contraindication in SPC and THES and do not administer/contraindication in LIV).

RESULTS

Among 239 subjects included, 60 (25.1%) had at least 1 DDI for a total of 126 DDIs: 23/126 red flag DDIs were identified in 17 patients. All these 23 DDIs were identified in LIV. THES and SPC missed 6 and 1 red flag DDIs, respectively. Seven of 23 red flag DDIs were identified in the 3 databases concomitantly.

CONCLUSION

Polypharmacy is frequent in this elderly HIV population leading to DDI in a quarter of the subjects. The discrepancies between databases can be explained by differences in analysis methods. A consensus between databases would be helpful for clinicians.

Prevalence and management of drug-drug interactions with antiretroviral treatment in 2069 people living with HIV in rural Tanzania: a prospective cohort study

OBJECTIVES

Widespread access to antiretroviral therapy (ART) has substantially increased life expectancy in sub-Saharan African countries. As a result, the rates of comorbidities and use of co-medications among people living with HIV are increasing, necessitating a sound understanding of drug-drug interactions (DDIs). We aimed to assess the prevalence and management of DDIs with ART in a rural Tanzanian setting.

METHODS

We included consenting HIV-positive adults initiating ART in the Kilombero and Ulanga Antiretroviral Cohort (KIULARCO) between January 2013 and December 2016. DDIs were classified using www.hiv-druginteractions.org as red (contra-indicated), amber (potential clinical relevance requiring dosage adjustment/monitoring), yellow (weak clinical significance unlikely to require further management) or green (no interaction). We assessed management of amber DDIs by evaluating monitoring of laboratory or clinical parameters, or changes in drug dosages.

RESULTS

Of 2069 participants, 1945 (94%) were prescribed at least one co-medication during a median follow-up of 1.8 years. Of these, 645 (33%) had at least one potentially clinically relevant DDI, with the highest grade being red in nine (< 1%) and amber in 636 (33%) participants. Of the 23 283 prescriptions, 19 (< 1%) and 1745 (7%) were classified as red and amber DDIs, respectively. Overall, 351 (2%) prescriptions were red DDIs or not appropriately managed amber DDIs.

CONCLUSIONS

Co-medication use was common in this rural sub-Saharan cohort. A third of participants had DDIs requiring further management. Of the 9% of participants with not appropriately managed DDIs, most were with cardiovascular and analgesic drugs. This highlights the importance of physicians' awareness of DDIs for their recognition and management.

Interactions of cobicistat and ritonavir in patients with HIV and its clinical consequences

INTRODUCTION

The prescription of antiretroviral treatment (ART) that contains pharmacokinetic enhancers such as ritonavir and cobicistat is frequent. The objective of this stdy was to analyze the potential interactions of ART that include these molecules in their formulation with the patient's home medication, as well as the clinical management of those potentially serious.

METHODS

Prospective study conducted in the pharmacy care clinic of a third level hospital between January and December of 2018. Those HIV+patients with an ART containing cobicistat or ritonavir were included in the study. Potential interactions between ART and concomitant medication were analysed in three databases (Micromedex®, Drugs.com and Liverpool), the interventions carried out were detailed, and adverse drug reactions analysed.

RESULTS

968 patients were included with a total of 2,148 prescriptions (274 different medications). A total of 86 interventions were performed regarding potential interactions in patients. The most frequent were substitutions of corticoid treatments, treatment suspensions and closer monitoring of treatments. A total of possible adverse drug reactions were analysed. The degree of agreement in the severity classification of the interactions for cobicistat and ritonavir was good among the three databases. It was remarkable Micromedex® as the most complete because it has more registered medications.

CONCLUSION

The interactions between ART with pharmacokinetic enhancers in its composition and concomitant medication is frequent and requires a significant variety of interventions. The check of interactions in different databases is recommended since they can cause adverse drug reactions.

Polypharmacy: a healthcare conundrum with a pharmacogenetic solution

The use of multiple medications is growing at an alarming rate with some reports documenting an average of 12-22 prescriptions being used by individuals ≥50 years of age. The indirect consequences of polypharmacy include exacerbation of drug-drug interactions, adverse drug reactions, increased likelihood of prescribing cascades, chronic dependence, and hospitalizations - all of which have significant health and economic burden. While many practical solutions for reducing polypharmacy have been proposed, they have been met with limited efficacy. This highlights the need for a new systematic approach for fine-tuning dispensing of medications. Pharmacogenetic testing provides an empirical and scientifically rigorous approach for guiding appropriate selection of medicines, with the potential to reduce unnecessary polypharmacy while improving clinical outcomes. The goal of this review article is to provide healthcare providers with an understanding of polypharmacy, its adverse effects on the healthcare system and highlight how pharmacogenetic information can be used to avoid polypharmacy in patients.

Anti-HIV and Anti-Hepatitis C Virus Drugs Inhibit P-Glycoprotein Efflux Activity in Caco-2 Cells and Precision-Cut Rat and Human Intestinal Slices

P-glycoprotein (ABCB1), an ATP-binding-cassette efflux transporter, limits intestinal absorption of its substrates and is a common site of drug-drug interactions (DDIs). ABCB1 has been suggested to interact with many antivirals used to treat HIV and/or chronic hepatitis C virus (HCV) infections. Using bidirectional transport experiments in Caco-2 cells and a recently established ex vivo model of accumulation in precision-cut intestinal slices (PCIS) prepared from rat ileum or human jejunum, we evaluated the potential of anti-HIV and anti-HCV antivirals to inhibit intestinal ABCB1. Lopinavir, ritonavir, saquinavir, atazanavir, maraviroc, ledipasvir, and daclatasvir inhibited the efflux of a model ABCB1 substrate, rhodamine 123 (RHD123), in Caco-2 cells and rat-derived PCIS. Lopinavir, ritonavir, saquinavir, and atazanavir also significantly inhibited RHD123 efflux in human-derived PCIS, while possible interindividual variability was observed in the inhibition of intestinal ABCB1 by maraviroc, ledipasvir, and daclatasvir. Abacavir, zidovudine, tenofovir disoproxil fumarate, etravirine, and rilpivirine did not inhibit intestinal ABCB1. In conclusion, using recently established ex vivo methods for measuring drug accumulation in rat- and human-derived PCIS, we have demonstrated that some antivirals have a high potential for DDIs on intestinal ABCB1. Our data help clarify the molecular mechanisms responsible for reported increases in the bioavailability of ABCB1 substrates, including antivirals and drugs prescribed to treat comorbidity. These results could help guide the selection of combination pharmacotherapies and/or suitable dosing schemes for patients infected with HIV and/or HCV.

Risk and Cost Associated With Drug-Drug Interactions Among Aging HIV Patients Receiving Combined Antiretroviral Therapy in France

Background

We aimed to describe the frequency, risk factors, and costs attributable to drug–drug interactions (DDIs) among an aging French HIV population.

Methods

We conducted a retrospective cohort study using French nationwide health care e-records: the SNIIRAM database. People living with HIV (PLWH) aged >65 years and receiving combined antiretroviral treatment (cART) during 2016 were included. A DDI was defined as “These drugs should not be co-administered,” represented by a red symbol on the University of Liverpool website. Attributable DDIs’ cost was defined as the difference between individuals with and without DDIs regarding all reimbursed health care acts.

Results

Overall, 9076 PLWH met the study criteria. Their baseline characteristics were: mean age, 71.3 ± 4.9 years; 25% female; median HIV duration (interquartile range [IQR]), 16.2 (9.5–20.3) years; median comorbidities (IQR), 2 (1–3). During 2016, they received a median (IQR) of 14 (9–21) comedications (non-cART), and 1529 individuals had at least 1 DDI (16.8%; 95% confidence interval [CI], 16.1–17.6). In multivariate analysis, raltegravir or dolutegravir plus 2 nucleoside reverse-transcriptase inhibitors (NRTIs) significantly and independently reduced the risk of DDIs (adjusted odds ratio [aOR], 0.02; 95% CI, 0.005–0.050; P < .0001) compared with non-nucleoside reverse-transcriptase inhibitor plus 2 NRTIs, whereas cART with boosted agents (protease inhibitors or elvitegravir) significantly increased the risk (aOR, 4.12; 95% CI, 3.34–5.10; P < .0001). Compared with propensity score–matched PLWH without DDIs, the presence of DDIs was associated with a $2693 additional cost per year (P < .0001).

Conclusions

The presence of DDIs is frequent and significantly increases health care costs in the aging population of PLWH.

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.