Every coin has two sides : the challenge of addressing inappropriate prescribing in older patients in primary care

Sammanfattning: Background: Drug-related morbidity contributes to every tenth unplanned hospital admission in older patients. A way to address this problem is to identify and minimize potentially inappropriate prescribing (PIP). Two important types of PIP are the use of contraindicated or excessively dosed drugs in patients with renal impairment and drug-disease interactions, where a drug worsens a concomitant disease. It is largely unknown how commonly older patients (≥ 65) are exposed to these two types of PIP. Similarly, there is insufficient knowledge on how general practitioners (GPs) and nurses in primary care should address PIP in their older patients. One important step in understanding how to address PIP is to investigate GPs’ and nurses’ views on PIP and medication reviews. Aim: 1) To increase knowledge on how commonly older patients in primary care are exposed to PIP in relation to renal function and drug-disease interactions; 2) To examine if an intervention on medication reviews combining several evidencebased educational strategies is a valuable measure to address PIP in primary care; and 3) To understand GPs’ and nurses’ views on PIP and medication reviews. Material and methods: Two cross-sectional population-based studies (I+II) in patients aged ≥65 in primary care in Stockholm County were performed. Drug dispense was assessed during one year. PIP in relation to renal function was assessed in patients with chronic kidney disease stage 3 (n=30 372) or 4 (n=2161) according to CKD-EPI formula (I). Drug-disease interactions were analyzed among 336 295 patients. PIP was addressed in a cluster-randomized controlled trial including 69 primary care practices (III). The multifaceted educational intervention targeted GPs and nurses, with the aim to promote medication reviews in accordance with a new regulation, thus reduce PIP and unplanned healthcare use. Data (I-III) were derived from regional and national registers (diagnoses, drugs, healthcare use) and SCREAM database (creatinine). Qualitative data were collected after each educational session and explored with thematic analysis (IV). Results: I: Contraindicated medicines were used by 9% of patients with chronic kidney disease stage 3 compared to 38% with stage 4, and excessive dosing was present in 43% vs. 58%, respectively. II: Drug-disease interactions were found in 10.8 % of older adults, the most common was hypertension/NSAID. I+II: A limited number of potentially inappropriate medicines explained the majority of PIP, such as NSAIDs (I + II) and drugs acting on the renin-angiotensin-aldosterone system (I). III: Neither PIP nor unplanned healthcare decreased after a multifaceted educational intervention in primary care. IV: A possible explanation for this result is the complexity of prescribing in older patients, as expressed by GPs and nurses. Conclusions: In patients with impaired renal function, excessive dosing was more common than the use of contraindicated medicines. Drug-disease interactions were less common than PIP in relation to renal function. Both types of PIP seem manageable as only a few medicines are implicated. Medication reviews that address PIP in its entirety are difficult to implement in primary care and may not improve prescribing in older patients. According to GPs and nurses, the complexity of PIP is a major challenge. Their efforts to improve prescribing are undermined by this complexity. In view of the potential harm of PIP in older patients, it is crucial to continue research on how it may be decreased.