Table 3.
Risk ratios for number of falls in the prior 3 months and prior-year emergency department visits among individuals with overlapping opioid and benzodiazepine prescriptions
| Falls* |
Emergency Department Visits† |
|||||
|---|---|---|---|---|---|---|
| RR | 95% CI | P Value | RR | 95% CI | P Value | |
| Overlapping benzodiazepine prescription | 3.27 | 1.77–6.02 | 0.0001 | 1.66 | 1.08–2.53 | 0.0194 |
| VAPORHCS | 1.98 | 1.04–3.78 | 0.039 | 3.82 | 2.27–6.45 | <0.0001 |
| Age (per 5-y increase) | 0.99 | 0.88–1.13 | 0.934 | 0.91 | 0.84–0.99 | 0.033 |
| Female | 1.93 | 1.07–3.50 | 0.029 | 1.64 | 1.00–2.68 | 0.048 |
| White race | 0.73 | 0.34–1.53 | 0.401 | 0.91 | 0.54–1.51 | 0.713 |
| Hispanic ethnicity | 0.87 | 0.22–3.37 | 0.840 | 0.56 | 0.21–1.50 | 0.251 |
| Up to or including high school diploma/GED‡ | 1.29 | 0.56–2.56 | 0.644 | 1.10 | 0.63–1.91 | 0.742 |
| Some college or technical school‡ | 0.74 | 0.41–1.33 | 0.312 | 1.11 | 0.70–1.74 | 0.658 |
| Morphine equivalent dose | 1.01 | 1.00–1.02 | 0.120 | 1.00 | 1.00–1.01 | 0.185 |
| Depression diagnosis | — | — | — | 0.87 | 0.58-1.33 | 0.538 |
| PTSD diagnosis | — | — | — | 0.76 | 0.45–1.28 | 0.307 |
| Bipolar diagnosis | — | — | — | 1.19 | 0.49–2.84 | 0.704 |
| Comorbidity index | 1.09 | 0.99–1.20 | 0.066 | 1.38 | 1.28–1.48 | <0.0001 |
| Substance/alcohol use disorder diagnosis | 0.41 | 0.16–1.09 | 0.075 | 0.78 | 0.42–1.44 | 0.430 |
| Antidepressant prescription | 1.31 | 0.79–2.18 | 0.295 | 0.74 | 0.50–1.10 | 0.138 |
| Sedative/hypnotic prescription | 3.57 | 1.73–7.35 | 0.001 | 0.92 | 0.56–1.52 | 0.750 |
This table presents the results of two separate multivariate negative binomial regressions on the risk of falling and emergency department visits comparing individuals with a co-prescription of benzodiazepines and opioids in the past year with individuals without those co-prescriptions. The RR represents the risks associated with the co-prescription of benzodiazepines and opioids, adjusting for all other covariates in the model. A propensity score derived from analyses presented in Table 2 was added to the outcome models to control for confounding. Depression, PTSD, and bipolar diagnoses were not included in the multivariate risk model for predicting falls as we had no a priori hypothesis about why these diagnoses would be associated with falling.
GED = General Equivalency Diploma; PTSD = post-traumatic stress disorder; RR = risk ratio; CI = confidence interval; VAPORHCS = VA Portland Health Care System.
Falls are continuous, self-reported (mean = 1.35, SD = 9.35).
Emergency department visits are a continuous measure derived from the electronic medical record.
Educational categories are compared with individuals with a college degree or higher.