Potential drug–drug interactions among prescriptionsfor elderly patients in primary health care

Abstract

IntroductionAlthough combination therapies are generally used to achieve better therapeutic results, drug-drug interactions (DDIs) can lead to life-threatening adverse reactions (ADRs) or therapeutic failure by changing the therapeutic efficacy of drugs. DDIs have been reported to cause 4% of drug-related emergency visits (1). Changes in the pharmacokinetic properties of drugs may produce adverse drug reactions or therapeutic failure. The pharmacodynamics of DDIs can produce additive, synergistic, or antagonistic pharmacological effects (2).ADRs can be considered an important public health problem, particularly in the elderly patients (3). Polypharmacy and DDIs play critical roles in the production of ADRs and are related to an increased risk of mortality (4,5). Among identified adverse drug events, preventable adverse drug events have been reported to be 27% in primary care and 42% in long-term care, where prescribing and monitoring stages of pharmaceutical care were emphasized for prevention of adverse drug events (6,7). Potentially inappropriate medications have been identified in Beers Criteria (8), which aimed to prevent poor outcomes in elderly patients such as ADRs, hospitalization, morbidity, or mortality (8). In the elderly population DDIs can be diagnosed as severe adverse outcomes (9). Increased sensitivity to DDIs in elderly patients and the most frequent ADRs experienced by this age group have been shown in many studies (10-12). Elderly patients exposed to polypharmacy are at high risk of DDIs that depend on agerelated changes in pharmacokinetics or pharmacodynamics of drugs, and multiple co-morbidities.Another important factor for the increased vulnerability of elderly patients to DDIs can be poor compliance, underuse, overuse, or misuse of the medications (13). Moreover, elderly patients who will undergo surgical treatment or treatment in an intensive care unit have been reported to have a high risk for the occurrence of DDIs ( 14). Although there are publications investigating the use of inappropriate drugs in Turkish elderly patients (15,16), there are no data evaluating potential DDIs in Turkish elderly patients.Background/aim: Elderly patients are at high risk from drug-drug interactions (DDIs). This study evaluates the potential DDIs in Turkish elderly patients at a primary health care outpatient clinic. Materials and methods:Online database systems were used to examine DDIs on the prescriptions of patients (n = 1206). The clinical severity of DDIs was classified by the Lexi-Interact Online database.Results: Of the 5059 prescriptions, 33% were found to have DDIs. We detected 29 (0.9%) A, 380 (11.8%) B, 2494 (77.7%) C, 289 (9%) D, and 18 (0.6%) X risk rating category DDIs among the prescriptions. Prescriptions of female patients and patients aged between 65 and 72 years showed significantly higher number of DDIs. The frequency of DDIs increased both with the number of drugs and combined preparations per prescription. Acetylsalicylic acid and salbutamol were the most frequently prescribed drugs ...

Drug-drug interactions and potentially inappropriate medications among elderly outpatients

“…In terms of significant interactions, a recent study on health claims data in Slovenia showed a prevalence of 28.1% for DDIs with D and X severity based on the Lexi-Interact in elderly outpatients (Jazbar et al, 2017), which is higher than our results (14.61%). However, in a study of the elderly in primary health care using the Lexi-Interact in Turkey, D and X interactions accounted for 10.96% of the sum of C, D, and X interactions (Gören et al, 2017), which is quite similar to our finding (11.69%). It was noted that the C interactions were the most prevalent DDIs reported in 76.2% of our prescriptions.…”

“…It seems that a consensus has not been achieved regarding the role of gender in this issue. In some previous studies of the elderly outpatients that reported a significantly higher DDI in women, the mean number of medications was not compared between genders nor was controlled (Gören et al, 2017). This was similar to a study in which higher clinically important potential DDIs were detected in the elderly women in the primary health system (Neto et al, 2012).…”

“…In other words, the higher prevalence of chronic illnesses in the elderly results in using multiple drugs concomitantly or polypharmacy (Rosa et al, 2016, Salwe, Kalyansundaram, Bahurupi, 2016, Sánchez-Fidalgo et al, 2017. Although these multiple medications are commonly administered to achieve a better therapeutic response, they can increase the risk of adverse drug reactions (ADRs) (Basnet et al, 2016;Scondotto et al, 2018), drug-drug interactions (DDIs) (Basnet et al, 2016;Gören et al, 2017;Hersh, Beldowski, Hajjar, 2017;Sánchez-Fidalgo et al, 2017) and medication costs (Basnet et al, 2016).…”

Assessment of Comorbidity and Use of Prescription and Nonprescription Drugs in Patients Above 65 Years Attending Family Medicine Outpatient Clinics

“…Older people are more vulnerable to morbidity and mortality secondary to drug-related harms because of age-related physiological changes and comorbidity of chronic conditions, such as cardiovascular diseases and mental disorders (Buffel du Vaure et al, 2016; GSA, 2013; Hines & Murphy, 2011). It was reported that approximately 30% of hospitalizations in elderly people were caused by adverse drug events (Goren, Demirkapu, Akpınar Acet, Cali, & Gülçebi İdrizoglu, 2017).…”

“…The noncontrolled use of these products may potentially lead to serious health problems in patients. Especially in elderly patients, drugs used without a physician recommendation may lead to several acute and chronic health problems such as drug–drug interactions, increased drug side effects, increased mortality and morbidity, and increased health expenditures (Bower et al, 2011; Gören et al, 2017; Hines & Murphy, 2011; Huntley, Johnson, Purdy, Valderas, & Salisbury, 2012; Olmos et al, 2012; Salisbury, Johnson, Purdy, Valderas, & Montgomery, 2011; Siddiqui, Min, Verma, & Jamshed, 2014). These products are used simultaneously with prescription drugs, may affect pharmacokinetic profiles of these medicines, may increase or decrease their effects, may cause undesirable side effects, and may trigger drug–drug interactions (Huntley et al, 2012; Siddiqui et al, 2014).…”