Frequent prescribing of drugs with potential gastrointestinal toxicity among continuous users of non-steroidal anti-inflammatory drugs

Objective: A number of drugs used concurrently with non-steroidal anti-inflammatory drugs (NSAIDs) increase the risk of gastrointestinal (GI) haemorrhage. We studied the prescribing of NSAIDs with corticosteroids, oral anticoagulants or selective serotonin re-uptake inhibitors (SSRIs), as well as the use of gastroprotection among continuous and non-continuous users of NSAIDs in Finland. Methods: Concurrent use of various drugs was analysed in a nested case-control study in a population-based cohort of NSAID users in 2000 using data in the National Prescription Database. Results: Prescribing of any other drug with the potential to increase the risk of GI bleeding with NSAIDs was five times [5.2; 95% confidence interval (CI) 4.7-5.9] more common among continuous than non-continuous NSAID users, and the odds ratio for oral corticosteroids was 8.0 (95% CI 6.6-9.6). Of patients using continuous NSAIDs with oral corticosteroids, 73.3% had rheumatoid arthritis (RA). After excluding RA patients, the odds ratio remained high (4.5; 95% CI 3.3-6. 1) and at the same level as for SSRIs (3.7; 3.1-4.4). Gastroprotective drugs were prescribed for 6.8% of the continuous users of NSAIDs alone, and for 20.4% of patients taking any of the studied drug combinations with NSAIDs. The continuous users of NSAIDs alone had gastroprotection 2.9 (2.5-3.3) times more often than other users of NSAIDs. With drug combinations (NSAID+corticosteroid, NSAID+SSRI, NSAID+anticoagulants), the use of gastroprotection did not differ from patients using lower amounts of NSAIDs. Conclusions: When prescribing NSAIDs, situations leading to habitual use should be avoided, potential complications due to clustering of risk factors recognised, and gastroprotection prescribed for patients with increased risk of GI haemorrhage.