Occurrence of Potential Prescribing Cascades After Hospital Discharge: A Cohort Study

A prescribing cascade (PC) occurs when a medication (index) causes an adverse drug reaction (ADR), which is addressed by prescribing additional medication (marker). Medication initiated in the hospital may cause post-discharge ADRs and PCs, especially when multiple healthcare providers are involved. The study aimed to assess the cumulative incidence of potential PCs post-discharge and identify the healthcare providers involved in prescribing the marker medication.

A cohort study was conducted among adult patients admitted in one hospital between 2019 and 2023, who initiated medication associated with preselected PCs (n = 20). A PC was defined as the initiation of a marker medication which may be intended to treat an ADR induced by the index medication. Data from the hospital and the Nationwide Medication Record System were used to identify potential PCs post-discharge. The primary outcome was the cumulative incidence of PCs, estimated for PCs with ≥ 10 patients initiating the index medication. The secondary outcome was the percentage of cases where the marker medication was prescribed by a healthcare provider outside the hospital, for PCs with ≥ 10 patients initiating the marker medication. Descriptive statistics were used.

Among 24 282 patients initiating index medication, 502 potential PCs were observed. The cumulative incidence was estimated for 17 PCs, ranging from 0% to 12.3%. Across 12 PCs with ≥ 10 patients, percentages of marker medications prescribed outside the hospital ranged from 31.8% to 92.8%.

The cumulative incidence of potential PCs post-discharge can be substantial with marker medication often initiated by healthcare providers outside the hospital.