3.3 Cumulative Defined Daily Dose of SSRIs and risk of UGIB
High cumulative SSRIs dose (>224 cDDDs) was associated with increased risk of UGIB, with low SSRI dose (<56 cDDDs) as the reference (adjusted OR: 1.28, 95% CI: 1.02–1.62) (Figure 2). For each SSRI, the risks of UGIB increased with increasing fluoxetine dose. The adjusted OR (95% CI) of UGIB was 1.44 (1.11–1.87) in the high cumulative dose group (≥150 cDDDs), 1.25 (0.96–1.63) in the median dose group (≥35 to <150 cDDDs), and 1.04 (0.78–1.39) in the low-dose group (<35 cDDDs), compared with the use of other classes of SSRIs. Paroxetine use was associated with statistically reduced risk of UGIB when taken in medium cumulative doses (30–134.5 cDDDs), not high doses (>134.5 cDDDs) (adjusted OR [95% CI], 0.57 [0.38–0.86] and 0.74 [0.51–1.09], respectively). No dose-related risks associated with other individual SSRIs were observed.