Medication Regimen Complexity and Hospital Readmission in Older Adults With Chronic Kidney Disease

Polypharmacy and medication regimen complexity in transfusion-dependent thalassaemia patients: a cross- sectional study

BACKGROUND

Medication burden and complexity have been longstanding problems in chronically ill patients. However, more data are needed on the extent and impact of medication burden and complexity in the transfusion-dependent thalassaemia population.

AIM

The aim of this study was to determine the characteristics of medication complexity and polypharmacy and determine their relationship with drug-related problems (DRP) and control of iron overload in transfusion-dependent thalassaemia patients.

METHOD

Data were derived from a cross-sectional observational study on characteristics of DRPs conducted at a Malaysian tertiary hospital. The medication regimen complexity index (MRCI) was determined using a validated tool, and polypharmacy was defined as the chronic use of five or more medications. The receiver operating characteristic curve analysis was used to determine the optimal cut-off value for MRCI, and logistic regression analysis was conducted.

RESULTS

The study enrolled 200 adult patients. The MRCI cut-off point was proposed to be 17.5 (Area Under Curve  =  0.722; sensitivity of 73.3% and specificity of 62.0%). Approximately 73% and 64.5% of the patients had polypharmacy and high MRCI, respectively. Findings indicated that DRP was a full mediator in the association between MRCI and iron overload.

CONCLUSION

Transfusion-dependent thalassaemia patients have high MRCI and suboptimal control of iron overload conditions in the presence of DRPs. Thus, future interventions should consider MRCI and DRP as factors in serum iron control.

Investigating the association between medication regimen complexity, medication adherence and treatment satisfaction among Malaysian older adult patients: a cross-sectional study

BACKGROUND

The prevalence of medication nonadherence among Malaysian older adults is approximately 60%. However, there is a lack of studies assessing the factors associated with medication nonadherence among this population. This research aims to explore the association between medication regimen complexity (MRC), treatment satisfaction and medication adherence among Malaysian older adults.

METHOD

A cross-sectional study was conducted in outpatient clinics of a teaching hospital in Pahang, Malaysia, between April 2023 and September 2023. MRC Index (MRCI), Treatment Satisfaction for Medication version II (TSQM v.II), and the Malaysian Medication Adherence Assessment Tool (MyMAAT) were used. Multivariate linear and logistic regression models were performed to test the factors affecting treatment satisfaction and medication adherence. Mediator analysis was implemented to assess the mediating role of treatment satisfaction.

RESULT

The study involved 429 Malaysian older adult patients, with a prevalence of nonadherence of 51.0% (n = 219) and an MRCI mean score of 17.37 (SD = 7.07). The mean overall treatment satisfaction score was 73.91 (SD = 15.23). Multivariate logistic regression analysis expressed four significant predictors associated with nonadherence: MRC (AOR = 1.179, p = 0.002), overall treatment satisfaction (AOR = 0.847, p < 0.001), partially self-managed medication (AOR = 2.675, p = 0.011) and fully managed medication by family members/caregivers (AOR = 8.436, p = 0.004). Multivariate linear regression shows three predictors of treatment satisfaction: MRC (β = -1.395, p < 0.001), Charlson Comorbidity Index (CCI) (β = -0.746, p = 0.009) and self-managed medication (β = 5.554, p = 0.006). Mediator analysis indicated that treatment satisfaction partially mediated the association between MRC and nonadherence.

CONCLUSION

Nonadherence was quite prevalent among Malaysian older outpatients and was associated with regimen complexity, treatment satisfaction and patient dependence on others to manage their medications. Future studies should focus on interventions to control the factors that negatively affect patients' medication adherence.

Short-term prognosis of polypharmacy in elderly patients treated in emergency departments: results from the EDEN project

Background

Polypharmacy is a growing phenomenon among elderly individuals. However, there is little information about the frequency of polypharmacy among the elderly population treated in emergency departments (EDs) and its prognostic effect. This study aims to determine the prevalence and short-term prognostic effect of polypharmacy in elderly patients treated in EDs.

Methods

A retrospective analysis of the Emergency Department Elderly in Needs (EDEN) project's cohort was performed. This registry included all elderly patients who attended 52 Spanish EDs for any condition. Mild and severe polypharmacy was defined as the use of 5-9 drugs and ⩾10 drugs, respectively. The assessed outcomes were ED revisits, hospital readmissions, and mortality 30 days after discharge. Crude and adjusted logistic regression analyses, including the patient's comorbidities, were performed.

Results

A total of 25,557 patients were evaluated [mean age: 78 (IQR: 71-84) years]; 10,534 (41.2%) and 5678 (22.2%) patients presented with mild and severe polypharmacy, respectively. In the adjusted analysis, mild polypharmacy and severe polypharmacy were associated with an increase in ED revisits [odds ratio (OR) 1.13 (95% confidence interval (CI): 1.04-1.23) and 1.38 (95% CI: 1.24-1.51)] and hospital readmissions [OR 1.18 (95% CI: 1.04-1.35) and 1.36 (95% CI: 1.16-1.60)], respectively, compared to non-polypharmacy. Mild and severe polypharmacy were not associated with increased 30-day mortality [OR 1.05 (95% CI: 0.89-2.26) and OR 0.89 (95% CI: 0.72-1.12)], respectively.

Conclusion

Polypharmacy was common among the elderly treated in EDs and associated with increased risks of ED revisits and hospital readmissions ⩽30 days but not with an increased risk of 30-day mortality. Patients with polypharmacy had a higher risk of ED revisits and hospital readmissions ⩽30 days after discharge.

Clinical pharmacy in hospital palliative medicine: non-randomised clinical trial

OBJECTIVE

To assess the impact of pharmaceutical care on hospital indicators and clinical outcomes of palliative care (PC) patients admitted to a secondary hospital.

METHODS

A non-randomised clinical trial was carried out in the PC ward of a secondary hospital in São Paulo, Brazil. Pharmaceutical care for all patients aged 18 and above, admitted between October 2021 and March 2022, with stays exceeding 48 hours, was provided. The interventions required were performed in collaboration with healthcare teams, patients and caregivers. Assessments occurred at admission and discharge, using PC performance scales and pharmacotherapy tools, with Research Ethics Committee approval.

RESULTS

Over 6 months, 120 hospitalisations were analysed, primarily involving women (58.9%), averaging 71.0 years, with neoplasm diagnoses (20.5%). A total of 170 drug-related problems were identified in 68.3% of patients. Following assessment, 361 interventions were performed, with a 78.1% acceptance rate, including medication dose adjustments, additions and discontinuations. Addressing unintentional pharmacotherapy discrepancies at admission led to reduced hospital stays (p<0.05). Pharmaceutical interventions also decreased pharmacotherapy complexity (p<0.001), inappropriate medications for the older people (p<0.001) and improved symptom management, such as pain (p<0.05).

CONCLUSIONS

Pharmaceutical care services integrated within the multiprofessional health team contributed to reducing drug-related problems associated with polypharmacy as well as improved the management PC symptoms in end-of-life patients, which reduced hospitalisation time.

Factors associated with readmission in chronic kidney disease: Systematic review and meta-analysis

BACKGROUND

Risk factors associated with all-cause hospital readmission are poorly characterised in patients with chronic kidney disease.

OBJECTIVE

A systematic review and meta-analysis were conducted to identify risk factors and protectors of hospital readmission in chronic kidney disease.

DESIGN, PARTICIPANTS & MEASUREMENTS

Studies involving adult patients were identified from four databases from inception to 31/03/2020. Random-effects meta-analyses were conducted to determine factors associated with all-cause 30-day hospital readmission in general chronic kidney disease, in dialysis and in kidney transplant recipient groups.

RESULTS

Eighty relevant studies (chronic kidney disease, n = 14 studies; dialysis, n = 34 studies; and transplant, n = 32 studies) were identified. Meta-analysis revealed that in both chronic kidney disease and transplant groups, increasing age in years and days spent at the hospital during the initial stay were associated with a higher risk of 30-day readmission. Other risk factors identified included increasing body mass index (kg/m2 ) in the transplant group, and functional impairment and discharge destination in the dialysis group. Within the chronic kidney disease ​​​​group, having an outpatient follow-up appointment with a nephrologist within 14 days of discharge was protective against readmission but this was not protective if provided by a primary care provider or a cardiologist.

CONCLUSION

Risk-reduction interventions that can be implemented include a nephrologist appointment within 14 days of hospital discharge, rehabilitation programme for functional improvement in the dialysis group and meal plans in the transplant group. Future risk analysis should focus on modifiable factors to ensure that strategies can be tested and implemented in those who are more at risk.

Evaluating the Medication Regimen Complexity Score as a Predictor of Clinical Outcomes in the Critically Ill

Background: Medication Regimen Complexity (MRC) refers to the combination of medication classes, dosages, and frequencies. The objective of this study was to examine the relationship between the scores of different MRC tools and the clinical outcomes. Methods: We conducted a retrospective cohort study at Roger William Medical Center, Providence, Rhode Island, which included 317 adult patients admitted to the intensive care unit (ICU) between 1 February 2020 and 30 August 2020. MRC was assessed using the MRC Index (MRCI) and MRC for the Intensive Care Unit (MRC-ICU). A multivariable logistic regression model was used to identify associations among MRC scores, clinical outcomes, and a logistic classifier to predict clinical outcomes. Results: Higher MRC scores were associated with increased mortality, a longer ICU length of stay (LOS), and the need for mechanical ventilation (MV). MRC-ICU scores at 24 h were significantly (p < 0.001) associated with increased ICU mortality, LOS, and MV, with ORs of 1.12 (95% CI: 1.06−1.19), 1.17 (1.1−1.24), and 1.21 (1.14−1.29), respectively. Mortality prediction was similar using both scoring tools (AUC: 0.88 [0.75−0.97] vs. 0.88 [0.76−0.97]. The model with 15 medication classes outperformed others in predicting the ICU LOS and the need for MV with AUCs of 0.82 (0.71−0.93) and 0.87 (0.77−0.96), respectively. Conclusion: Our results demonstrated that both MRC scores were associated with poorer clinical outcomes. The incorporation of MRC scores in real-time therapeutic decision making can aid clinicians to prescribe safer alternatives.

Risk of 30-day hospital readmission associated with medical conditions and drug regimens of polymedicated, older inpatients discharged home: a registry-based cohort study

OBJECTIVES

The present study analysed 4 years of a hospital register (2015-2018) to determine the risk of 30-day hospital readmission associated with the medical conditions and drug regimens of polymedicated, older inpatients discharged home.

DESIGN

Registry-based cohort study.

SETTING

Valais Hospital-a public general hospital centre in the French-speaking part of Switzerland.

PARTICIPANTS

We explored the electronic records of 20 422 inpatient stays by polymedicated, home-dwelling older adults held in the hospital's patient register. We identified 13 802 hospital readmissions involving 8878 separate patients over 64 years old.

OUTCOME MEASURES

Sociodemographic characteristics, medical conditions and drug regimen data associated with risk of readmission within 30 days of discharge.

RESULTS

The overall 30-day hospital readmission rate was 7.8%. Adjusted multivariate analyses revealed increased risk of hospital readmission for patients with longer hospital length of stay (OR=1.014 per additional day; 95% CI 1.006 to 1.021), impaired mobility (OR=1.218; 95% CI 1.039 to 1.427), multimorbidity (OR=1.419 per additional International Classification of Diseases, 10th Revision condition; 95% CI 1.282 to 1.572), tumorous disease (OR=2.538; 95% CI 2.089 to 3.082), polypharmacy (OR=1.043 per additional drug prescribed; 95% CI 1.028 to 1.058), and certain specific drugs, including antiemetics and antinauseants (OR=3.216 per additional drug unit taken; 95% CI 1.842 to 5.617), antihypertensives (OR=1.771; 95% CI 1.287 to 2.438), drugs for functional gastrointestinal disorders (OR=1.424; 95% CI 1.166 to 1.739), systemic hormonal preparations (OR=1.207; 95% CI 1.052 to 1.385) and vitamins (OR=1.201; 95% CI 1.049 to 1.374), as well as concurrent use of beta-blocking agents and drugs for acid-related disorders (OR=1.367; 95% CI 1.046 to 1.788).

CONCLUSIONS

Thirty-day hospital readmission risk was associated with longer hospital length of stay, health disorders, polypharmacy and drug regimens. The drug regimen patterns increasing the risk of hospital readmission were very heterogeneous. Further research is needed to explore hospital readmissions caused solely by specific drugs and drug-drug interactions.

Differential Diagnoses and Clinical Implications of Medication Nonadherence in Older Patients with Chronic Kidney Disease: A Review

Older adults with chronic kidney disease (CKD) often have many comorbidities, which requires them to take multiple medications. As the number of daily medications prescribed increases, the risk for polypharmacy increases. Understanding and improving medication adherence in this patient population is vital to avoiding the drug-related adverse events of polypharmacy. The primary objective of this review is to summarize the existing literature and to understand the factors leading to medication nonadherence in older patients with CKD. In this review, we discuss the prevalence of polypharmacy, the current lack of consensus on the incidence of medication nonadherence, the heterogeneity of assessing medication adherence, and the most common differential diagnoses for medication nonadherence in this population. Specifically, the most common differential diagnoses for medication nonadherence in older adults with CKD are (1) medication complexity; (2) cognitive impairment; (3) low health literacy; and (4) systems-based barriers. We provide tailored strategies to address these differential diagnoses and subsequently improve medication adherence. The clinical implications include deprescribing to decrease medication complexity and polypharmacy, utilizing a team-based approach to identify and support patients with cognitive impairment, enriching communication between health providers and patients with low health literacy, and improving health care access to address systems-based barriers. Further research is needed to determine the effects of addressing these differential diagnoses and medication adherence in older adults with CKD.

Assessing the Population-Level Correlation of Medication Regimen Complexity and Adherence Indices Using Electronic Health Records and Insurance Claims

BACKGROUND

Nonadherence to medication regimens can lead to adverse health care outcomes and increasing costs.

OBJECTIVES

To (a) assess the level of medication complexity at an outpatient setting using population-level electronic health record (EHR) data and (b) evaluate its association with medication adherence measures derived from medication-dispensing claims.

METHODS

We linked EHR data with insurance claims of 70,054 patients who had an encounter with a U.S. midwestern health system between 2012 and 2013. We constructed 3 medication-derived indices: medication regimen complexity index (MRCI) using EHR data; medication possession ratio (MPR) using insurance pharmacy claims; and prescription fill rates (PFR; 7 and 30 days) using both data sources. We estimated the partial correlation between indices using Spearman's coefficient (SC) after adjusting for age and sex.

RESULTS

The mean age (SD) of 70,054 patients was 37.9 (18.0) years, with an average Charlson Comorbidity Index of 0.308 (0.778). The 2012 data showed mean (SD) MRCI, MPR, and 30-day PFR of 14.6 (17.8), 0.624 (0.310), and 81.0 (27.0), respectively. Patients with previous inpatient stays were likely to have high MRCI scores (36.3 [37.9], P < 0.001) and were less adherent to outpatient prescriptions (MPR = 50.3 [27.6%], P < 0.001; 30-day PFR = 75.7 [23.6%], P < 0.001). However, MRCI did not show a negative correlation with MPR (SC = -0.31, P < 0.001) or with 30-day PFR (SC = -0.17, P < 0.001) at significant levels.

CONCLUSIONS

Medication complexity and adherence indices can be calculated on a population level using linked EHR and claims data. Regimen complexity affects patient adherence to outpatient medication, and strength of correlations vary modestly across populations. Future studies should assess the added values of MRCI, MPR, and PFR to population health management efforts.

DISCLOSURES

No outside funding supported this study. The authors have nothing to disclose. The abstract of this work was presented at INFORMS Healthcare Conference, held on July 27-29, 2019, in Cambridge, MA.

Medication-related hospital admissions and readmissions in older patients: an overview of literature

Background The number of medication related hospital admissions and readmissions are increasing over the years due to the ageing population. Medication related hospital admissions and readmissions lead to decreased quality of life and high healthcare costs. Aim of the review To assess what is currently known about medication related hospital admissions, medication related hospital readmissions, their risk factors, and possible interventions which reduce medication related hospital readmissions. Method We searched PubMed for articles about the topic medication related hospital admissions and readmissions. Overall 54 studies were selected for the overview of literature. Results Between the different selected studies there was much heterogeneity in definitions for medication related admission and readmissions, in study population and the way studies were performed. Multiple risk factors are found in the studies for example: polypharmacy, comorbidities, therapy non adherence, cognitive impairment, depending living situation, high risk medications and higher age. Different interventions are studied to reduce the number of medication related readmission, some of these interventions may reduce the readmissions like the participation of a pharmacist, education programmes and transition-of-care interventions and the use of digital assistance in the form of Clinical Decision Support Systems. However the methods and the results of these interventions show heterogeneity in the different researches. Conclusion There is much heterogeneity in incidence and definitions for both medication related hospital admissions and readmissions. Some risk factors are known for medication related admissions and readmissions such as polypharmacy, older age and additional diseases. Known interventions that could possibly lead to a decrease in medication related hospital readmissions are spare being the involvement of a pharmacist, education programs and transition-care interventions the most mentioned ones although controversial results have been reported. More research is needed to gather more information on this topic.

Medication Complexity among Disadvantaged African American Seniors in Los Angeles

Background. Several publications highlight data concerning multiple chronic conditions and the medication regimen complexity (MRC) used in managing these conditions as well as MRCs’ association with polypharmacy and medication non-adherence. However, there is a paucity of literature that specifically details the correlates of MRC with multimorbidity, socioeconomic, physical and mental health factors in disadvantaged (medically underserved, low income) African American (AA) seniors. Aims. In a local sample in South Los Angeles, we investigated correlates of MRC in African American older adults with chronic disease(s). Methods. This was a community-based survey in South Los Angeles with 709 African American senior participants (55 years and older). Age, gender, continuity of care, educational attainment, multimorbidity, financial constraints, marital status, and MRC (outcome) were measured. Data were analyzed using linear regression. Results. Higher MRC correlated with female gender, a higher number of healthcare providers, hospitalization events and multimorbidity. However, there were no associations between MRC and age, level of education, financial constraint, living arrangements or health maintenance organization (HMO) membership. Conclusions. Disadvantaged African Americans, particularly female older adults with multimorbidity, who also have multiple healthcare providers and medications, use the most complex medication regimens. It is imperative that MRC is reduced particularly in African American older adults with multimorbidity.

Impact of Medication Regimen Simplification on Medication Administration Times and Health Outcomes in Residential Aged Care: 12 Month Follow Up of the SIMPLER Randomized Controlled Trial

In the SImplification of Medications Prescribed to Long-tErm care Residents (SIMPLER) cluster-randomized controlled trial, we evaluated the impact of structured medication regimen simplification on medication administration times, falls, hospitalization, and mortality at 8 residential aged care facilities (RACFs) at 12 month follow up. In total, 242 residents taking ≥1 medication regularly were included. Opportunities for simplification among participants at 4 RACFs were identified using the validated Medication Regimen Simplification Guide for Residential Aged CarE (MRS GRACE). Simplification was possible for 62 of 99 residents in the intervention arm. Significant reductions in the mean number of daily medication administration times were observed at 8 months (-0.38, 95% confidence intervals (CI) -0.69 to -0.07) and 12 months (-0.47, 95%CI -0.84 to -0.09) in the intervention compared to the comparison arm. A higher incidence of falls was observed in the intervention arm (incidence rate ratio (IRR) 2.20, 95%CI 1.33 to 3.63) over 12-months, which was primarily driven by a high falls rate in one intervention RACF and a simultaneous decrease in comparison RACFs. No significant differences in hospitalizations (IRR 1.78, 95%CI 0.57-5.53) or mortality (relative risk 0.81, 95%CI 0.48-1.38) over 12 months were observed. Medication simplification achieves sustained reductions in medication administration times and should be implemented using a structured resident-centered approach that incorporates clinical judgement.

Emergency department visits of older adults within 30 days of discharge: analysis from the pharmacotherapy perspective

OBJECTIVE

To analyze, from the pharmacotherapy perspective, the factors associated to visits of older adults to the emergency department within 30 days after discharge.

METHODS

A cross-sectional study carried out in a general public hospital with older adults. Emergency department visit was defined as the stay of the older adult in this service for up to 24 hours. The complexity of drug therapy was determined using the Medication Regimen Complexity Index. Potentially inappropriate drugs for use in older adults were classified according to the American Geriatric Society/Beers criteria of 2015. The outcome investigated was the frequency of visits to the emergency department within 30 days of discharge. Multivariate logistic regression was performed to identify the factors associated with the emergency department visit.

RESULTS

A total of 255 elderly in the study, and 67 (26.3%) visited emergency department within 30 days of discharge. Polypharmacy and potentially inappropriate medications for older adults did not present a statistically significant association. The diagnosis of heart failure and Medication Regimen Complexity Index >16.5 were positively associated with emergency department visits (OR=2.3; 95%CI: 1.04-4.94; p=0.048; and OR=2.1; 95%CI: 1.11-4.02; p=0.011), respectively. Furthermore, the diagnosis of diabetes mellitus and chronic kidney disease were protection factors for the outcome (OR=0.4; 95%CI: 0.20-0.73; p=0.004; and OR=0.3; 95%CI: 0.13-0.86; p=0.023).

CONCLUSION

The diagnosis of heart failure and Medication Regimen Complexity Index >16.5 were positively associated with the occurrence of an emergency department visit within 30 days of discharge.

Multimorbidity and healthcare resource utilization in Switzerland: a multicentre cohort study

BACKGROUND

Multimorbidity is associated with higher healthcare resource utilization, but we lack data on the association of specific combinations of comorbidities with healthcare resource utilization. We aimed to identify the combinations of comorbidities associated with high healthcare resource utilization among multimorbid medical inpatients.

METHODS

We performed a multicentre retrospective cohort study including 33,871 multimorbid (≥2 chronic diseases) medical inpatients discharged from three Swiss hospitals in 2010-2011. Healthcare resource utilization was measured as 30-day potentially avoidable readmission (PAR), prolonged length of stay (LOS) and difference in median LOS. We identified the combinations of chronic comorbidities associated with the highest healthcare resource utilization and quantified this association using regression techniques.

RESULTS

Three-fourths of the combinations with the strongest association with PAR included chronic kidney disease. Acute and unspecified renal failure combined with solid malignancy was most strongly associated with PAR (OR 2.64, 95%CI 1.79;3.90). Miscellaneous mental health disorders combined with mood disorders was the most strongly associated with LOS (difference in median LOS: 17 days) and prolonged LOS (OR 10.77, 95%CI 8.38;13.84). The number of chronic diseases was strongly associated with prolonged LOS (OR 9.07, 95%CI 8.04;10.24 for ≥10 chronic diseases), and to a lesser extent with PAR (OR 2.16, 95%CI 1.75;2.65 for ≥10 chronic diseases).

CONCLUSIONS

Multimorbidity appears to have a higher impact on LOS than on PAR. Combinations of comorbidities most strongly associated with healthcare utilization included kidney disorders for PAR, and mental health disorders for LOS.

The effect of age on short-term postoperative complications following arthroscopic rotator cuff repair

Hypothesis

The purpose of this study was to assess short-term outcomes, including the rates of medical complications, non-home discharge, overnight hospital stay, and 30-day readmission, associated with patient age at the time of rotator cuff repair.

Methods

This study used National Surgical Quality Improvement Program data from 2005 to 2016 to analyze patients who underwent arthroscopic rotator cuff repair (ARCR). Patients were stratified into age cohorts of younger than 55 years, between 55 and 65 years, or older than 65 years. Outcomes including postoperative complications, discharge destination, and readmission were compared between the age cohorts using multivariate analysis.

Results

We identified 23,974 patients undergoing ARCR: 8344 patients (34.8%) were younger than 55 years, 9166 (38.4%) were aged between 55 and 65 years, and 6434 (26.8%) were older than 65 years. Older patients were more likely to be female patients and to have a lower body mass index, more medical comorbidities, shorter operative duration, dependent functional status, and higher American Society of Anesthesiologists classification. Patients older than 65 years had a higher rate of total complications (odds ratio [OR], 1.99; P = .003), respiratory complications (OR, 2.99; P = .023), urinary tract infections (OR, 6.94; P < .001), overnight hospital stay (OR, 1.49; P < .001), and unplanned hospital readmission (OR, 1.50; P = .040) relative to patients younger than 55 years. There was no increase in complication rates for patients aged between 55 and 65 years.

Conclusions

Patients older than 65 years have nearly double the odds of having a postoperative complication following ARCR and nearly 3 and 6 times the odds of having a respiratory complication and a urinary tract complication, respectively. Thorough preoperative optimization, including respiratory and urinary care, may be able to decrease complications in select, high-risk patients.

Medication-Related Factors and Hospital Readmission in Older Adults with Chronic Kidney Disease

This study aimed to examine the association between medication-related factors and risk of hospital readmission in older patients with chronic kidney disease (CKD). A retrospective analysis was conducted targeting older CKD (n = 204) patients admitted to an Australian hospital. Medication appropriateness (Medication Appropriateness Index; MAI), medication regimen complexity (number of medications and Medication Regimen Complexity Index; MRCI) and use of selected medication classes were exposure variables. Outcomes were occurrence of readmission within 30 and 90 days, and time to readmission within 90 days. Logistic and Cox hazards regression were used to identify factors associated with readmission. Overall, 50 patients (24%) were readmitted within 30 days, while 81 (40%) were readmitted within 90 days. Mean time to readmission within 90 days was 66 (SD 34) days. Medication appropriateness and regimen complexity were not independently associated with 30- or 90-day hospital readmissions in older adults with CKD, whereas use of renin‒angiotensin blockers was associated with reduced occurrence of 30-day (adjusted OR 0.39; 95% CI 0.19⁻0.79) and 90-day readmissions (adjusted OR 0.45; 95% CI 0.24⁻0.84) and longer time to readmission within 90 days (adjusted HR 0.52; 95% CI 0.33⁻0.83). This finding highlights the importance of considering the potential benefits of individual medications during medication review in older CKD patients.