Risk of pneumonia using propensity score matching for risk of pneumonia among participants taking and not taking benzodiazepines and Z-drugs
| Comparison | No. of participants included | No. of cases of pneumonia | Person-years of follow-up | No. of diagnoses of pneumonia per 100 person-years (95% CI) | PS-matched HR (95% CI) | PS-matched and time-dependent adjustment for other psychotropic drugs HR (95% CI)*,†,‡ |
|---|---|---|---|---|---|---|
| Any benzodiazepine and Z-drug use | ||||||
| No use of benzodiazepines or Z-drugs | 8501 | 1135 | 17 967 | 6.32 (6.28–6.35) | Ref. | Ref. |
| Use of benzodiazepines or Z-drugs | 8501 | 566 | 6993 | 8.10 (8.03–8.16) | 1.24 (1.07–1.43) | 1.22 (1.05–1.42) |
| Benzodiazepine use | ||||||
| No use of benzodiazepines or Z-drugs | 5232 | 713 | 10 846 | 6.57 (6.53–6.62) | Ref. | Ref. |
| Use of benzodiazepines | 5232 | 394 | 4629 | 8.51 (8.43–8.60) | 1.31 (1.10–1.56) | 1.28 (1.07–1.54) |
| Interval of benzodiazepine use, d | ||||||
| 0–30 | 5232 | 46 | 421 | 10.92 (10.60–11.23) | 2.09 (1.26–3.48) | |
| 31–180 | 4856 | 124 | 1398 | 8.87 (8.71–9.02) | 1.27 (0.96–1.67) | |
| 181–365 | 2207 | 77 | 930 | 8.28 (8.09–8.46) | 1.16 (0.80–1.69) | |
| 366–1095 | 1468 | 117 | 1534 | 7.63 (7.49–7.76) | 1.23 (0.85–1.76) | |
| ≥ 1096 | 322 | 30 | 360 | 8.33 (8.04–8.64) | 1.40 (0.44–4.41) | |
| Z-drug use | ||||||
| No use of benzodiazepines or Z-drugs | 3269 | 422 | 7121 | 5.92 (5.87–5.98) | Ref. | |
| Use of Z-drugs | 3269 | 172 | 2363 | 7.28 (7.17–7.39) | 1.11 (0.86–1.43) | 1.10 (0.84–1.44) |
| Interval of Z-drug use, d | ||||||
| 0–30 | 3269 | 24 | 257 | 9.34 (9.27–9.41) | 1.60 (0.84–3.05) | |
| 31–180 | 2719 | 51 | 665 | 7.67 (7.46–7.88) | 0.88 (0.59–1.32) | |
| 181–365 | 1044 | 29 | 440 | 6.60 (6.36–6.84) | 1.14 (0.64–2.02) | |
| 366–1095 | 708 | 53 | 794 | 6.67 (6.43–6.91) | 1.19 (0.67–2.13) | |
| ≥ 1096 | 189 | 15 | 216 | 6.95 (6.76–7.13) | 1.75 (0.51–5.98) | |
Note: CI = confidence interval, HR = hazard ratio, PS = propensity score, Z-drug = non-benzodiazepine drug with similar activity to benzodiazepine.
↵* Main analyses in time-dependent model, HR (95%CI): antipsychotic use, 1.18 (0.90–1.54); antidepressant use, 0.79 (0.62–1.02); and opioid use, 2.23 (1.50–3.31).
↵† Benzodiazepine analyses in time-dependent model, HR (95% CI): antipsychotic use, 1.22 (0.88–1.68); antidepressant use, 0.83 (0.61–1.14); and opioid use, 2.09 (1.32–3.35).
↵‡ Analyses of Z-drugs in time-dependent model, HR (95%CI): antipsychotic use, 1.10 (0.67–1.81); antidepressant use, 0.71 (0.46–1.11); and opioid use, 2.60 (1.25–5.42).