TABLE 2.
Medication usage by age-group and study period.
| All years | Period 1 | Period 2 | ||
|---|---|---|---|---|
| 2007–2018 | 2007–2012 | 2013–2018 | ||
| N = 692,522 | N = 304,378 | N = 388,144 | ||
| No. Of admissions with recorded medications, n (%) | N (%) | N (%) | N (%) | Period 2 vs period 1 IRR (95% CI) a p-value |
| 18–35 years | 40,177 (31.0) | 19,548 (34.05) | 20,629 (28.5) | 0.838 (0.822, 0.855)p < 0.001 |
| 35–49 years | 47,387 (41.7) | 23,541 (44.8) | 23,846 (39.1) | 0.873 (0.857, 0.889)p < 0.001 |
| 50–64 years | 66,380 (46.3) | 30,187 (46.6) | 36,197 (46.0) | 0.986 (0.971, 1.002)p = 0.080 |
| 65–79 years | 77,518 (45.1) | 32,875 (44.3) | 44,643 (45.7) | 1.032 (1.017, 1.047)p < 0.001 |
| 80 + years | 69, 036 (51.5) | 28,242 (50.9) | 40,794 (51.9) | 1.021 (1.005, 1.036)p = 0.009 |
| All ages | 300,498 (43.4) | 134,410 (44.15) | 166,105 (42.8) | 0.969 (0.962, 0.976)p < 0.001 |
| No. Medications for medicated admissions | Mean (SD) | Mean (SD) | Mean (SD) | IRR (95% CI) b Period 2 vs Period 1 p-value |
| 18–35 years | 3.09 (2.45) | 3.09 (2.30) | 3.09 (2.58) | 1.000 (0.983, 1.015)0.908 |
| 35–49 years | 4.71 (3.91) | 4.60 (3.79) | 4.81 (4.02) | 1.046 (1.030, 1.061)<0.001 |
| 50–64 years | 6.55 (4.56) | 6.21 (4.25) | 6.83 (4.79) | 1.100 (1.088, 1.112)<0.001 |
| 65–79 years | 8.28 (4.76) | 8.00 (4.46) | 8.49 (4.96) | 1.061 (1.053, 1.070)<0.001 |
| 80 + years | 9.22 (4.48) | 9.10 (4.34) | 9.30 (4.57) | 1.022 (1.015, 1.030)<0.001 |
| All ages | 6.86 (4.77) | 6.52 (4.53) | 7.13 (4.93) | 1.093 (1.088, 1.099)<0.001 |
| No. Medications for all admissions | Mean (SD) | Mean (SD) | Mean (SD) | IRR (95% CI) b Period 2 vs Period 1 p-value |
| 18–35 years | 0.96 (1.97) | 1.05 (1.99) | 0.88 (1.96) | 0.837 (0.819, 0.853)<0.001 |
| 35–49 years | 1.96 (3.43) | 2.06 (3.42) | 1.88 (3.44) | 0.913 (0.895, 0.932)<0.001 |
| 50–64 years | 3.03 (4.50) | 2.89 (4.25) | 3.14 (4.70) | 1.085 (1.068, 1.102)<0.001 |
| 65–79 years | 3.74 (5.22) | 3.54 (4.96) | 3.88 (5.40) | 1.095 (1.081, 1.110)<0.001 |
| 80 + years | 4.75 (5.62) | 4.63 (5.50) | 4.83 (5.70) | 1.043 (1.030, 1.057)<0.001 |
| All ages | 2.97 (4.63) | 2.88 (4.42) | 3.05 (4.78) | 1.060 (1.052, 1.068)<0.001 |
N, Number; CI, Confidence Interval; IRR, Incidence rate ratio; SD, standard deviation.
a
Using negative binomial regression and robust standard errors with period as the independent variable and medicated/non-medicated status as the dependent variable.
b
Using negative binomial regression with period as the independent variable and the number of medications recorded for each admission as the dependent variable.