4CPS-023 Occurrence of potential prescribing cascades after hospital discharge: a cohort study

<h3>Background and Importance</h3> A prescribing cascade occurs when a first (index) medication causes an adverse drug reaction, which is subsequently addressed by prescribing an additional (marker) medication. Medication started in the hospital can cause post-discharge adverse drug reactions and prescribing cascades, especially because multiple healthcare providers (HCPs) are involved in the post-discharge period. It is unknown how often prescribing cascades occur post-discharge. <h3>Aim and Objectives</h3> To assess the cumulative incidence of 20 potential prescribing cascades post-discharge and to identify the HCPs involved in prescribing the marker. <h3>Material and Methods</h3> A cohort study was conducted in a teaching hospital with adult patients admitted between 2019 and 2023, who started an index medication related to a potential prescribing cascade during their hospital stay. Data from the hospital and the Nationwide Medication Record System were used to identify patients with a potential prescribing cascade within a year post-discharge (if patients provided consent for information exchange). The primary outcome was the cumulative incidence of the prescribing cascade (calculated when ≥10 patients initiated the index medication). The secondary outcome was the number of prescribing cascades for which ≥50% of marker medication was prescribed by HCPs from outside the hospital (calculated when ≥10 patients initiated the marker medication). Data analysis was performed using descriptive statistics. <h3>Results</h3> Of 24,282 patients prescribed a new index medication, 502 experienced a potential prescribing cascade. Cumulative incidence was calculated for 17 prescribing cascades, ranging from 0% to 12.3% (mean age: 68.9 years, standard deviation 11.8). For nine out of 12 prescribing cascades the marker medication was started by HCPs from outside the hospital in ≥50% of patients. Examples included ACE-inhibitors causing cough followed by antitussives (cumulative incidence 5.4%, 92.8% started by HCPs outside the hospital), dihydropyridines causing peripheral oedema followed by high-ceiling diuretics (cum. incidence 6.3%), and amiodarone causing hypothyroidism followed by thyroid hormones (cum. incidence 4.0%). <h3>Conclusion and Relevance</h3> The cumulative incidence of potential prescribing cascades post-discharge can be substantial, frequently involved older adults and most marker medication were prescribed by another HCP. Our study underscores the need for improved monitoring and increased recognition of adverse drug reactions to prevent prescribing cascades post-discharge. Hospital pharmacists can play a key role in this. <h3>References and/or Acknowledgements</h3> <h3>Conflict of Interest</h3> No conflict of interest