Prevalence, severity, and nature of risk factors associated with drug-drug interactions in geriatric patients receiving cancer chemotherapy: A prospective study in a tertiary care teaching hospital

Drug-related problems among esophageal, gastric and colorectal cancer patients at the National and referral hospital in Kenya

INTRODUCTION

Cancer therapy has remarkable potential for drug-related problems due to the high cytotoxicity and narrow therapeutic index of most anti-neoplastic regimens. However, there is a lack of comprehensive studies on drug-related problems in patients with gastrointestinal cancer in Kenya. Therefore, the present study aimed to investigate the prevalence, types and predictors of drug-related problems among gastrointestinal cancer patients at Kenyatta National Hospital.

METHODS

A cross-sectional study was used to assess the prevalence of drug-related problems among a random sample of 160 esophageal, 103 gastric, and 96 colorectal cancer patients. Data were collected using a researcher-administered questionnaire and data abstraction tool after training the data collectors. Patient-specific details such as socio-demographic features, histological cancer types, cancer stage, comorbidity types, and treatment regimen were recorded after the review of medical records and patient interviews. The potential of drug-related problems was determined as per the standard guidelines. The data were entered and analysed using version 26.0 SPSS statistical software.

RESULTS

Most esophageal (51.9%), gastric (59.2%), and colorectal (62.5%) cancer patients had a high prevalence of drug-related problems. The need for additional drug therapy and adverse drug reactions were the predominant categories of drug-related problems. Most adverse drug reactions identified had possible categories of causality score, mild severity levels, and definitely preventable types of adverse drug reactions among all gastrointestinal cancer patients. Comorbidity and advanced-stage disease were significant predictors of drug-related problems.

CONCLUSIONS

Drug-related problems were prevalent among gastrointestinal cancer patients in our setting. Comorbidity and advanced stages of disease were significant predictors of drug-related problems.

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.

Polypharmacy and potentially-inappropriate medications are prevalent in the elderly cancer patients receiving systemic cancer therapy and they co-relate with adverse outcomes

OBJECTIVES

Cancer is the disease of the ageing. Most of the elderly cancer patients have pre-existing illnesses requiring complexity of medical care. Excessive medications would lead not only futility, but also result in adverse outcomes especially if such over-prescription is not appropriate. This study was intended to determine the prevalence of polypharmacy (PP) and potentially-inappropriate medications (PIMs) among elderly cancer patients eligible for active cancer care and their associations with hospitalization and mortality.

MATERIALS AND METHODS

This was a prospective cohort study conducted among the elderly non-hematologic cancer patients (≥ 65 years old) whom a medical oncologist had decided suitable for systemic cancer therapy. Demographic data including age, sex, primary site of cancer, cancer stage at diagnosis, Charlson Comorbidity Index (CCI), numbers and kinds of medications used both prior to and during cancer treatment were recorded. Hospitalizations not related to systemic cancer therapy administration and mortality were prospectively monitored. All of the patients had to be followed at least one year after cancer diagnosis.

RESULTS

There were 180 eligible participants. Median age in years (IQR) was 68 (65-73). One hundred patients (55.56%) were male and 80 patients (44.44%) were female. Breast (35, 19.44%), lung (31, 17.22%) and colorectal (18, 10%) cancers were the most common diagnoses. Eighty-six patients (47.78%) had metastatic disease at cancer diagnosis. One hundred twenty-two patients (67.78%) had PP (5 or more medications a day) and thirty-six patients (20%) had hyper-PP (10 or more medications a day). One hundred twenty five of the whole cohort (69.4%) had PIMs. Patients with more serious CCI scores were associated with PP and hyper-PP. While patients with primary lung cancer was only the only factor associated with PIMs. When excluding opioids, laxatives and anti-emetics, the most frequently prescribed drugs during cancer treatment, the so-called corrected PP did not associate with worse 1-year survival. Factors correlated with 1-year mortality were more advanced age group (70 years old or more) (OR 2.24; 95% C.I., 1.14-4.41; p = 0.019), primary lung cancer (OR 2.89; 95% C.I., 1.45-5.78; p = 0.003), metastatic disease at cancer diagnosis (OR 4.57; 95% C.I., 1.90-10.97; p = 0.001), and unplanned hospitalizations (OR 3.09; 95% C.I.,1.60-5.99; p = 0.001). While male gender (OR 2.35; 95% C.I., 1.17-4.71; p = 0.016), metastatic stage at cancer diagnosis (OR 2.74; 95% C.I., 1.33-5.66; p = 0.006) and corrected PP (OR 1.90; 95% C.I. 1.01-3.56; p = 0.046) were the significant predictive factors of unplanned hospitalizations.

CONCLUSION

Among elderly cancer patients suitable for systemic cancer therapy, around two thirds of patients had PP and PIMs. Higher CCI score was the only significant predictor of PP and hyper-PP; while primary lung cancer was the sole independent factor predicting PIMs. PP was associated with unplanned hospitalizations, albeit not the survival.

TOP-PIC: a new tool to optimize pharmacotherapy and reduce polypharmacy in patients with incurable cancer

PURPOSE

Polypharmacy is a significant problem in patients with incurable cancer and a method to optimize pharmacotherapy in this patient group is lacking. Therefore, a drug optimization tool was developed and tested in a pilot test.

METHODS

A multidisciplinary team of health professionals developed a "Tool to Optimize Pharmacotherapy in Patients with Incurable Cancer" (TOP-PIC) for patients with a limited life expectancy. The tool consists of five sequential steps to optimize medications, including medication history, screening for medication appropriateness and drug interactions, a benefit-risk assessment using the TOP-PIC Disease-based list, and shared decision-making with the patient. For pilot testing of the tool, 8 patient cases with polypharmacy were analyzed by 11 oncologists before and after training with the TOP-PIC tool.

RESULTS

TOP-PIC was considered helpful by all oncologists during the pilot test. The median additional time required to administer the tool was 2 min per patient (P < 0.001). For 17.4% of all medications, different decisions were made by using TOP-PIC. Among possible treatment decisions (discontinuation, reduction, increase, replacement, or addition of a drug), discontinuation of medications was the most common. Without TOP-PIC, physicians were uncertain in 9.3% of medication changes, compared with only 4.8% after using TOP-PIC (P = 0.001). The TOP-PIC Disease-based list was considered helpful by 94.5% of oncologists.

CONCLUSIONS

TOP-PIC provides a detailed, disease-based benefit-risk assessment with recommendations specific for cancer patients with limited life expectancy. Based on the results of the pilot study, the tool seems practicable for day-to-day clinical decision-making and provides evidence-based facts to optimize pharmacotherapy.

Frequency, severity, and factors associated with clinically significant drug-drug interactions among patients with cancer attending Mbarara Regional Referral Hospital Cancer Unit, Uganda

BACKGROUND

Cancer is a major public health problem with pharmacotherapy being the cornerstone of its management. Cancer patients receive multiple drugs concurrently risking Drug-Drug Interactions (DDIs). DDIs, though avoidable, can significantly contribute to morbidity, mortality, and increased healthcare costs in this population of patients. Currently, there is no published study from Uganda on clinically significant DDIs (cs-DDIs) among cancer patients. This study identifies frequency, severity, and factors associated with cs-DDIs at Mbarara Regional Referral Hospital Cancer Unit (MRRHCU).

METHOD

A cross-sectional study was conducted among 300 cancer patients receiving chemotherapy from a tertiary care hospital in western Uganda from January-February 2022. A questionnaire and data collection form were used to collect patient data. Lexicomp® Drug interaction software was used to screen the patient drug information for DDIs and assess their severity. Predictors of DDIs were identified using logistic regression using SPSS (Statistical Package for Social Sciences).

RESULT

Three hundred participants were enrolled with a mean age of 48 ± 23.3 years. One hundred eighty-one patients experienced 495 cs-DDIs; with a mean of 1.7 ± 2.2. The prevalence of cs-DDI was 60.3% (55.0-66.0% at 95% CI). Digestive organ neoplasms were the most commonly (80, 26.7%) diagnosed category, and 'plant alkaloids and other natural products were the most frequently (143, 47.7%) used chemotherapeutic drug classes. About three-quarters of cs-DDIs were rated as category C risk (367, 74.1%) whereas over two-thirds (355, 71.7%) were moderate in severity.. Being female (aOR = 2.43 [1.23-4.48 at 95% CI]; P-value = 0.011) and use of ≥ 6 drugs concurrently (aOR = 18.82 [9.58-36.95 at 95% CI]; P-value < 0.001)) were significantly associated with cs-DDIs.

CONCLUSION

More than half of the participants experienced at-least one cs-DDI which is generally higher than what was reported in high-income settings. About three-quarters were category C and moderate in severity, and require enhanced monitoring for safety and treatment outcome. Being female and using ≥ 6 drugs were significantly associated with cs-DDIs.

The Prevalence of Drug-Drug Interactions and Reported Therapy Related Side Effects in Oncology Out-Patients

Objective: The use of multiple medications in cancer patients is unavoidable; thus, adverse drug-drug interactions are frequent. This study aims to assess the prevalence of potential drug interactions in oncology patients visiting the outpatient chemotherapy unit. Method: Demographic and health-related information of patients visiting an outpatient chemotherapy unit was recorded using a pre-prepared form. A comprehensive list of all concurrently used medications was compiled and checked for interactions with the Micromedex online drug interaction tool. Results: A total of 179 adult patients were included. We recorded an average of 9.3 drugs per patient with 79 patients using more than 10 drugs. A total of 1671 drugs including 303 chemotherapeutic agents were assessed for drug-drug interactions. A total of 374 interactions, of which 203 were significant, were recorded in 118 (65.9%) patients with an average of 3.2 interactions per patient. Only 46 major interactions were recorded for anticancer agents. Cyclophosphamide (n=13) and cisplatin (n=12) were involved in most interactions. The number of interactions correlated with the number of drugs used (p=.001) and the presence of comorbidities (p=.002). The presence of comorbidities increased the risk of interaction by 1.21 (p=.04). Recorded side effects were not correlated to drug interactions. Conclusion: Medication review in cancer patients is essential in establishing all medications used by patients. Routine assessment in terms of potential drug interactions and evaluation of these interactions by a qualified pharmacist may help in optimizing patient outcomes.

A comprehensive evaluation of potentially significant drug-drug, drug-herb, and drug-food interactions among cancer patients receiving anticancer drugs

INTRODUCTION

During the cancer treatment path, cancer patients use numerous drugs, including anticancer, supportive, and other prescribed medications, along with herbs and certain products. This puts them at risk of significant drug interactions (DIs). This study describes DIs in cancer patients and their prevalence and predictors.

METHODS

A cross-sectional study design was used to achieve the study objectives. The study was carried out in two centers in the northern West Bank, Palestine. The Lexicomp® Drug Interactions tool (Lexi-Comp, Hudson OH, USA) was applied to check the potential DIs. In addition, the Statistical Package for the Social Sciences (SPSS) was used to show the results and find the associations.

RESULTS

The final analysis included 327 patients. Most of the participants were older than 50 years (61.2%), female (68.5%), and had a solid tumor (74.6%). The total number of potential DIs was 1753, including 1510 drug-drug interactions (DDIs), 24 drug-herb interactions, and 219 drug-food interactions. Importantly, the prevalence of DDIs was 88.1%. In multivariate analysis, the number of potential DDIs significantly decreased with the duration of treatment (p = 0.007), while it increased with the number of comorbidities (p < 0.001) and the number of drugs used (p < 0.001).

CONCLUSIONS

We found a high prevalence of DIs among cancer patients. This required health care providers to develop a comprehensive protocol to monitor and evaluate DIs by improving doctor-pharmacist communication and supporting the role of clinical pharmacists.