| No acupuncture | Acupuncture treatment |  |  | ||||||
---|---|---|---|---|---|---|---|---|---|---|
 | n | Events | Person-years | Incidenceb | n | Events | Person-years | Incidenceb | HR | (95 % CI) |
Alla | 46950 | 3915 | 361501 | 10.8 | 23475 | 1376 | 149047 | 9.2 | 0.86 | (0.80–0.93) |
Sex | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â |
 Female | 20098 | 1160 | 117882 | 9.8 | 10049 | 402 | 46412 | 8.7 | 0.85 | (0.76–0.95) |
 Male | 26852 | 1818 | 147873 | 12.3 | 13426 | 652 | 60251 | 10.8 | 0.87 | (0.80–0.95) |
Age, years | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â |
 40–49 | 3994 | 172 | 24672 | 7.0 | 1997 | 56 | 9388 | 6.0 | 0.84 | (0.62–1.14) |
 50–59 | 9274 | 536 | 56522 | 9.5 | 4637 | 160 | 21818 | 7.3 | 0.75 | (0.63–0.90) |
 60–69 | 16796 | 1125 | 97436 | 11.5 | 8398 | 390 | 38813 | 10.0 | 0.85 | (0.75–0.95) |
 70–79 | 16886 | 1145 | 87126 | 13.1 | 8443 | 448 | 36643 | 12.2 | 0.93 | (0.83–1.03) |
Subtypes of stroke | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â |
 Hemorrhagic | 4408 | 151 | 24568 | 6.1 | 2204 | 41 | 10327 | 4.0 | 0.62 | (0.44–0.88) |
 Ischemic | 27096 | 1847 | 150560 | 12.3 | 13548 | 671 | 62138 | 10.8 | 0.87 | (0.79–0.95) |
 Others | 15446 | 980 | 90628 | 10.8 | 7723 | 342 | 34199 | 10.0 | 0.89 | (0.79–1.01) |