Medication-related patient harm in New Zealand hospitals.

Aim: The purpose of this study is to identify patterns of medication-related harm from a national perspective, and to use this information to inform decisions on where to focus medication safety efforts. This study updates a 2013 study using the same methodology.

Method: District health boards (DHBs) still actively using either the Adverse Drug Event (ADE) Trigger Tool (TT) or the Global Trigger Tool (GTT), submitted two years of anonymised ADE data (1 July 2013-30 June 2015) to the Health Quality & Safety Commission (the Commission) using a standard template. Analyses were conducted using aggregated data only.

Results: Of eight DHBs who submitted data, six datasets were included, representing a total of 2,659 chart reviews. From these reviews, 923 harms were identified in 751 patients, with 28% of patients experiencing one or more harms. Harms occurred at a rate of 34.7 per 100 admissions, 42.5 per 1,000 bed days and 28% of patients experienced one or more medication-related harms. Those harmed were more likely to be older, female and have an increased length of stay. Most harms (65%) occurred during an inpatient stay, however, a substantial number (29%) originated in the community and precipitated an admission. Across all levels of severity, the most common types of medication harm were constipation, hypotension and bleeding. In the more serious harm categories, bleeding, hypotension and delirium/confusion/over-sedation were most common. Six groups of medicines caused the greatest amount of harm: opioids (including tramadol), anticoagulants/antiplatelet agents, antibiotics, antianginals (beta-blockers, nitrates, calcium channel blockers and others), diuretics and other cardiovascular medicines (angiotensin-converting enzyme (ACE) inhibitors, angiotensin II receptor antagonists (ARBs), centrally acting agents and statins). Opioids and anticoagulants/antiplatelet agents not only accounted for 40% of all harm, they were implicated in the most severe harm.

Conclusion: This paper confirms earlier work that medication-related harms are common, occur both in hospitals and in the community, and are a substantial burden for patients and our healthcare system. Work is underway at local and national levels to decrease this harm, with a focus on the high-risk medicines most commonly implicated.