Preferences about Future Alzheimer's Disease Treatments Elicited through an Online Survey Using the Threshold Technique.

BACKGROUND: Treatments aiming at slowing down the progression of Alzheimer's disease (AD) may soon become available. However, information about the risks that people are willing to accept in order to delay the progression of the disease is limited. OBJECTIVE: To determine the trade-offs that individuals are willing to make between the benefits and risks of hypothetical treatments for AD, and the extent to which these trade-offs depend on individuals' characteristics and beliefs about medicines. DESIGN: Online, cross-sectional survey study. SETTING: Population in the UK. Public link to the survey available at the websites of Alzheimer's Research UK and Join Dementia Research. PARTICIPANTS: Everyone self-reported ≥18 years old was eligible to participate. A total of 4384 people entered the survey and 3658 completed it. MEASUREMENTS: The maximum acceptable risks (MARs) of participants for moderate and severe adverse events in exchange for a 2-year delay in disease progression. The risks were expressed on ordinal scales, from <10% to ≥50%, above a pre-existing risk of 30% for moderate adverse events and 10% for severe adverse events. We obtained the population median MARs using log-normal survival models and quantified the effects of individuals' characteristics and beliefs about medicines in terms of acceleration factors. RESULTS: For the moderate adverse events, 26% of the participants had a MAR ≥50%, followed by 25% of the participants with a MAR of 10 to <20%, giving an estimated median MAR of 25.4% (95% confidence interval [CI] 24.5 to 26.3). For the severe adverse events, 43% of the participants had a MAR <10%, followed by 25% of the participants with a MAR of 10 to <20%, resulting in an estimated median MAR of 12.1% (95%CI 11.6 to 12.5). Factors that were associated with the individuals' MARs for one or both adverse events were age, gender, educational level, living alone, and beliefs about medicines. Whether or not individuals were living with memory problems or had experience as a caregiver had no effect on the MARs for any of the adverse events. CONCLUSION: Trade-offs between benefits and risks of AD treatments are heterogeneous and influenced by individuals' characteristics and beliefs about medicines. This heterogeneity should be acknowledged during the medicinal product decision-making in order to fulfil the needs of the various subpopulations.

Cost-effectiveness of an electronic medication ordering system (CPOE/CDSS) in hospitalized patients.

INTRODUCTION: Prescribing medication is an important aspect of almost all in-hospital treatment regimes. Besides their obviously beneficial effects, medicines can also cause adverse drug events (ADE), which increase morbidity, mortality and health care costs. Partially, these ADEs arise from medication errors, e.g. at the prescribing stage. ADEs caused by medication errors are preventable ADEs. Until now, medication ordering was primarily a paper-based process and consequently, it was error prone. Computerized Physician Order Entry, combined with basic Clinical Decision Support System (CPOE/CDSS) is considered to enhance patient safety. Limited information is available on the balance between the health gains and the costs that need to be invested in order to achieve these positive effects. Aim of this study was to study the balance between the effects and costs of CPOE/CDSS compared to the traditional paper-based medication ordering. METHODS: The economic evaluation was performed alongside a clinical study (interrupted time series design) on the effectiveness of CPOE/CDSS, including a cost minimization and a cost-effectiveness analysis. Data collection took place between 2005 and 2008. Analyses were performed from a hospital perspective. The study was performed in a general teaching hospital and a University Medical Centre on general internal medicine, gastroenterology and geriatric wards. Computerized Physician Order Entry, combined with basic Clinical Decision Support System (CPOE/CDSS) was compared to a traditional paper based system. All costs of both medication ordering systems are based on resources used and time invested. Prices were expressed in Euros (price level 2009). Effectiveness outcomes were medication errors and preventable adverse drug events. RESULTS: During the paper-based prescribing period 592 patients were included, and during the CPOE/CDSS period 603. Total costs of the paper-based system and CPOE/CDSS amounted to €12.37 and €14.91 per patient/day respectively. The Incremental Cost-Effectiveness Ratio (ICER) for medication errors was 3.54 and for preventable adverse drug events 322.70, indicating the extra amount (€) that has to be invested in order to prevent one medication error or one pADE. CONCLUSIONS: CPOE with basic CDSS contributes to a decreased risk of preventable harm. Overall, the extra costs of CPOE/CDSS needed to prevent one ME or one pADE seem to be acceptable.

When direct health-care professional communications have an impact on inappropriate and unsafe use of medicines.

Serious safety issues relating to drugs are communicated to health-care professionals via Direct Health-Care Professional Communications (DHPCs). We explored which characteristics determined the impact of DHPCs issued in the Netherlands for ambulatory-care drugs (2001-2008). With multiple linear regression, we examined the impact on the relative change in new drug use post-DHPC of the following: time to DHPC, trend in use, degree of innovation, specialist drug, first/repeated DHPC, DHPC template, and type of safety issue. DHPCs have less impact on use of specialist drugs than nonspecialist drugs (P < 0.05). The DHPCs' impact increased after availability of a template emphasizing the main problem (P < 0.05), and for safety issues with a risk of death and/or disability (both P < 0.05) (adjusted R² = 0.392). Risk communication can be effective, specifically in case of well-structured information, and very serious safety issues. Effectiveness may improve by tailoring DHPCs and adding other communication channels, for example for drugs that are increasingly being used.

Impact of safety-related regulatory action on drug use in ambulatory care in the Netherlands.

The effect of Direct Healthcare Professional Communications (DHPCs) informing health-care providers of serious drug safety issues has been questioned. The aim of this study was to evaluate the impact of DHPCs on drug use.Nationwide dispensing data for the period 2000­2008 for new users of 46 drugs with one or more DHPCs were assessed. Impact on short-term volume of use was evaluated with regression models, and the presence of long-term changes in use was evaluated with interrupted time series analyses incorporating preexisting trends. The short-term prescription level was lower post-DHPC in 28 (48.3%) of 58 cases. Twenty (34.5%) DHPCs resulted in long-term changes in use. A long-term mean reduction in use was observed in 26.7% of cases (95% confidence interval, −15.2 to −38.2%).Long-term changes in use were not significantly related to preexisting trends in use. Although short- and long-term decreases in use were observed after only half and a third of DHPCs, respectively, the decrease was substantial.

Medication errors: the impact of prescribing and transcribing errors on preventable harm in hospitalised patients.

BACKGROUND: Medication errors (MEs) affect patient safety to a significant extent. Because these errors can lead to preventable adverse drug events (pADEs), it is important to know what type of ME is the most prevalent cause of these pADEs. This study determined the impact of the various types of prescribing (administrative, dosing and therapeutic) and transcribing errors on pADEs in hospitalised patients. METHODS: During a 5-month period, data for patients admitted to a total of five internal medicine wards of one university and one teaching hospital in The Netherlands were prospectively collected by chart review. In each hospital, MEs were detected and classified by the same pharmacist, using the classification scheme for MEs developed by The Netherlands Association of Hospital Pharmacists. The primary outcome measure was the prevalence of pADEs during hospital stay. In consensus meetings, five pharmacists assessed the causal relationship between MEs and pADEs. The association between type of ME and pADEs was determined by a multivariate regression analysis taking into account potential confounders. RESULTS: The study included 592 hospital admissions with 7286 medication orders (MOs), of which 60% contained at least one prescribing or transcribing error. 1.4% of all MOs led to pADEs, concerning 14.8% of all admitted patients. The total number of pADEs was 103, and in 92 of these cases patients experienced temporary harm, in eight cases hospital admission was prolongued, two cases were life-threatening, and one was fatal. Therapeutic errors were most strongly associated with pADEs (OR 1.98; 95% CI 1.53 to 2.56). CONCLUSIONS: Although many prescribing and transcribing errors occur in the process of medication use of hospitalised patients, a minority lead to pADEs. In particular, therapeutic errors are the cause of these pADEs and are therefore clinically relevant. Intervention and prevention programmes should primarily focus on this type of medication error.

Influence of renal dysfunction on the pharmacokinetics of the selective Na+/H+ exchange inhibitor EMD 87 580 in patients with chronic heart failure.

BACKGROUND: Chronic heart failure (CHF) is a potential indication for the administration of EMD 87 580, a selective Na+/H+ exchange inhibitor. CHF is often accompanied by renal dysfunction, which is known to affect the pharmacokinetics of compounds predominately cleared by the kidneys. We examined the influence of renal dysfunction on the pharmacokinetics of EMD 87 580 in patients with CHF. METHODS: 21 patients with CHF and normal renal function (Group 1) and 9 patients with CHF and renal dysfunction (Group 2) received EMD 87 580 orally over 8 days. The mean creatinine clearance (CrCl) in Group 1 was 99.7 ml/min. 12 patients in this group were randomized to receive two doses of EMD 87 580 (7 patients 2 x 50 mg and 5 patients 2 x 100 mg). The 9 patients in Group 2 with renal dysfunction (mean CrCl = 49.5 ml/min) received 50 mg EMD 87 580 once daily. Plasma and urine samples were collected for pharmacokinetic assessment. RESULTS: In CHF patients with renal dysfunction EMD 87 580 clearance was reduced to approximately 50% compared to Group 1, i.e. 6.80 ml/min (4.89-11.60) vs. 12.73 ml/min (8.93-22.21), p < 0.05, for the 50 mg dose and 14.08 ml/min (9.96-18.10), p < 0.05, for the 100 mg dose. Consequently, plasma concentrations were increased in patients with renal dysfunction; AUC0-infinity 7,354 ng/ml x h (4,311-10,232) vs. 3,928 ng/ml x h (2,251-5,596, 50 mg dose, p < 0.05). A significant correlation was observed between EMD 87 580 plasma clearance and CrCl (r2 = 0.8062). CONCLUSION: In CHF patients with renal dysfunction EMD 87 580, clearance is reduced and plasma concentrations increased. Therefore, dose adjustments for EMD 87 580 are indicated in patients with CHF and renal dysfunction.

Reliability of assessment of adherence to an antimicrobial treatment guideline.

Assessment procedures for adherence to a guideline must be reliable and credible. The aim of this study was to explore the reliability of assessment of adherence, taking account of the professional backgrounds of the observers. A secondary analysis explored the impact of case characteristics on assessment. Six observers (two hospital pharmacists, two internists and two clinical microbiologists) assessed a random sample of 22 prescriptions made to infectious disease cases admitted to a department of internal medicine between February and August 2001. Agreement between observers with regard to adherence of these prescriptions to guideline recommendations concerning drug choice, duration of treatment, dosage and route of administration was measured using Cohen's kappa. Case characteristics were compared between cases where observers agreed and disagreed with two-sided Fisher's exact test. Agreement between all professionals was moderate for drug choice (0.59), fair for duration of therapy (0.36), moderate for dosage (0.48), and fair for route of administration (0.37). Agreement on drug choice was good within (0.75 and 0.83) and between (0.74) the internists and the hospital pharmacists, but was less within (0.31) the clinical microbiologists and between the clinical microbiologists and the internists (0.44) and the hospital pharmacists (0.42). Within the clinical microbiologists, agreement was good for dosage (0.79) and route of administration (0.66). There was frequent disagreement between observers regarding cases with combination therapy and non-immunocompromised patients. Despite the small number of cases, our results suggest that internists and hospital pharmacists can reliably be used to assess adherence for drug choice. The level of agreement seems to be affected by combination therapy and the immune status of the patient.