Figure 2 illustrates unadjusted Kaplan-Meier curves for survival probability at the start of follow-up, for which unadjusted log-rank tests showed that all-cause mortality was significantly elevated in the benzodiazepine-opioid cotreatment group in comparison with those taking benzodiazepines only, opioids only, and SSRI recipients taking neither (χ2 = 22.41; P < .001). Among those who were 65 years or younger, we calculated an event rate of 10.3 per 1000 person-years in comparison with 59.9 per 1000 person-years among their peers older than 65 years (eTable 3 in the Supplement).
