Identification of risks for drug-related problems

Drug-related problems (DRPs) are defined as an event or circumstance involving drug therapy that actually or potentially interferes with desired health outcomes. DRPs are common and occur at every stage of care. They are responsible for patient harm and cause substantial additional healthcare cost. A considerable amount of DRPs is judged by the literature as preventable.
Inappropriate prescribing (IP) constitutes a major risk for the occurrence of DRPs and is highly prevalent, especially in the elderly, where polymorbidity and polypharmacy are often part of everyday life. An appropriate prescription of medication should “maximize efficacy and safety, minimise cost, and respect patient‘s preferences”.
Clinical pharmacy (CP) is an area of pharmacy with the aim of developing and promoting the appropriate, safe and cost-effective use of therapeutic products. A clinical pharmacist assumes responsibility for managing medication therapy in direct patient care. CP services for in-patients have a beneficial effect on patient safety by reducing medication errors and adverse drug events; they are effective in improving the patients knowledge about drug therapy and their adherence. The involvement of a clinical pharmacist who provides clinical pharmacy services such as patient counselling and medication review has proved to be a successful approach to support the physician in reducing IP.
Numerous tools for the assessment of IP have been published and can be a valuable aid during the physicians prescribing process or a medication review of a pharmacist. Until today a comprehensive and structured overview of existing tools has not been available.
In most European countries, staffing restrictions are a major barrier for the development of CP services. At the same time, an impressively growing drug market and an increasing number of elderly patients with complex polypharmacy demand the need for clinical pharmacists. To meet the requirements of optimising patient’s drug therapies while at the same time dealing with limited capacity, pharmacists are forced to target their clinical activities to those patients who are most likely to benefit from them ─ that is, to focus on those who are at the highest risk of experiencing DRPs.
This thesis aimed to create a comprehensive overview on available tools for the assessment of IP. In a second part, a risk assessment tool for the occurrence of DRPs should be developed to enable pharmacists to target their clinical activities on high-risk patients.
In project A, a systematic literature search on PUBMED resulted in 46 tools for the assessment of IP, all different in terms of IP content, structure and length, targeted health care settings (hospital care, ambulatory care, long-term care) and patient groups (elderly, all age), development method (literature review, expert panels and/or consensus techniques) and extent of validation. By outlining the characteristics of each tool in a highly structured manner, we created a survey, which did not identify a single ideal tool but who revealed their strengths and weaknesses what may help readers to choose one, either for research purposes or for use in daily practice, according to the situation in which it is intended to be applied.
In project B we developed a risk assessment tool, to support pharmacists in focussing their clinical activities. The development of such a risk assessment tool required in a first step an identification of risk factors (RFs). As RFs for the occurrence of DRPs are numerous, they cannot be fully covered by an IP assessment tool.
In project B1 we therefore intended to get a broader impression on possible RFs for the occurrence of DRPs. We conducted a multidisciplinary expert panel, using the nominal group technique (NGT) and a qualitative analysis to gather risk factors for DRPs. The literature was searched for additional risk factors. Gathered factors from the literature search and the NGT were assembled and validated in a two-round Delphi questionnaire. This approach resulted in a final list of 27 RFs judged by the experts to be “important” or “rather important” for the occurrence of DRPs.
In project B2 we developed the Drug Associated Risk Tool (DART) out of the RFs that we identified in project B1. We conducted a prospective validation study with 164 patients and validated the DART concerning feasibility, acceptability and reliability of patients answers. Feasibility and acceptability of the DART were satisfactory. Compared to other risk assessment tools, summarized in a separate overview B3, the DART reached a high overall specificity of 95% and a slightly low overall sensitivity of 58%.
From the results and experiences of this thesis the following conclusions could be drawn:
• Inappropriate prescribing (IP) is a major risk for the occurrence of DRPs. The avoidance of IP should not only be the task of the physician but shared between different healthcare providers in order to guarantee the most appropriate therapy. Tools for the assessment of IP can provide a useful aid to evaluate the appropriateness of a therapy, during a medication review, or during the process of prescribing itself.
• Inappropriate prescribing assessment tools are numerous. They show a large variety in structure, degree of comprehensiveness and extend of validation. By providing an overview of published assessment tools, this thesis may assist healthcare providers to choose a tool, either for research purposes or for use in daily practice, according to the situation in which it is intended to be applied.
• The Drug Associated Risk Tool (DART) is a promising approach for clinical pharmacists to assess patients at risk for the development of DRPs and thereby target their clinical pharmacy activities to those patients who benefit the most thereof.
• The DART is based on a combination of a systematic literature search, with the professional experience and knowledge of a multidisciplinary expert panel, which enabled the comprehensive finding of risk factors for DRPs representing the real-life situation in the Swiss healthcare setting.
• A first technical validation of the DART was successful and supported the concept of a patient self-assessment. Compared to similar self-assessment tools, the DART has comparable complexity and comprehensiveness, has an appealing design and shows a satisfactory validation concerning feasibility, acceptability and reliability of patients’ answers.
We saw a lower sensitivity of the DART compared to similar risk self-assessments. We proposed potential issues that might have affected the sensitivity of our tool: The understandability of the questions, the accuracy of medical histories and medical data and the reliability of patient answers. A rephrasing of the statements with very low sensitivity values with the aim of improving the understanding of the question followed by a second validation with a most accurate medication list is recommended. A validation with clinical outcomes is crucial to prove the concept of our risk assessment.