Is there overuse of proton pump inhibitors in B-cell non-Hodgkin lymphomas? A cohort study based on the French health insurance database in the Midi-Pyrénées region.

Patients suffering from B-cell non-Hodgkin lymphomas (B-NHL) have an increased likelihood of being exposed to proton pump inhibitors (PPIs), related to several factors which have been reported in the literature. PPIs are among the drugs most likely to be prescribed inappropriately. Consequently, B-NHL patients could be particularly at risk of inappropriate PPI prescription, with potential adverse drug reactions. We aimed to evaluate the incidence of PPIs use and to identify factors associated with PPIs initiation during the active treatment phase of B-NHL. We conducted a new-user cohort study using regional data from the French national health insurance database in the Midi-Pyrénées region (southwestern France). Incident B-NHL patients were selected according to an algorithm of selection, validated with data from a cancer registry. Our study revealed that 48.9% (95% confidence interval [CI]: 45.2-52.6) of patients initiated PPIs during chemotherapy after B-NHL diagnosis. According to information available in the SNDS, recommended indications for PPI prescriptions were identified in 21.1% of cases. Median duration of treatment was 65.3 days (CI: 35-112). Determinants of PPIs initiation were peptic ulcer disease, gastroprotection (appropriate or not) for medications considered at risk (NSAIDs, glucocorticoids and anticoagulants), age, nonfollicular lymphoma, polypharmacy, gastroenterologists' consultations and being hospitalized in a university hospital. Around 50% of patients initiated PPI treatment during the chemotherapy phase with only one-fifth identified as appropriate prescriptions and with long durations of treatment in most cases. Given this background, appropriate PPI prescription should be promoted in B-NHL to avoid potential inappropriate chronic use and related adverse events.