Table 2.
Incidence of amputations per 1000 patient-years by sex and age categories at baseline with 95% CIs estimated by exact Poisson confidence limits
| Event | Subgroup | Statistics | All | Men | Women | |||
| Type 1 diabetes | Controls | Type 1 diabetes | Controls | Type 1 diabetes | Controls | |||
| Any amputation | All | n (%, N) | 1081 (3.0, 36 577) | 117 (0.1, 182 617) | 711 (3.6, 20 010) | 80 (0.1, 99 879) | 370 (2.2, 16 567) | 37 (0.0, 82 738) |
| Event rate (95% CI) | 3.18 (2.99 to 3.38) | 0.07 (0.05 to 0.08) | 3.87 (3.59 to 4.17) | 0.08 (0.07 to 0.10) | 2.37 (2.13 to 2.62) | 0.05 (0.03 to 0.06) | ||
| 18–49 years | n (%, N) | 428 (1.4, 29 578) | 31 (0.0, 147 804) | 276 (1.7, 16 305) | 23 (0.0, 81 463) | 152 (1.1, 13 273) | 8 (0.0, 66 341) | |
| Event rate (95% CI) | 1.54 (1.40 to 1.70) | 0.02 (0.01 to 0.03) | 1.82 (1.62 to 2.05) | 0.03 (0.02 to 0.04) | 1.21 (1.02 to 1.42) | 0.01 (0.01 to 0.02) | ||
| 50–64 years | n (%, N) | 474 (8.6, 5533) | 41 (0.1, 27 588) | 325 (11.0, 2968) | 26 (0.2, 14 792) | 149 (5.8, 2565) | 15 (0.1, 12 796) | |
| Event rate (95% CI) | 8.91 (8.13 to 9.75) | 0.14 (0.10 to 0.18) | 11.70 (10.46 to 13.04) | 0.16 (0.11 to 0.24) | 5.87 (4.96 to 6.89) | 0.11 (0.06 to 0.17) | ||
| 65+ years | n (%, N) | 179 (12.2, 1466) | 45 (0.6, 7225) | 110 (14.9, 737) | 31 (0.9, 3624) | 69 (9.5, 729) | 14 (0.4, 3601) | |
| Event rate (95% CI) | 18.65 (16.02 to 21.60) | 0.74 (0.54 to 0.99) | 24.05 (19.77 to 28.99) | 1.06 (0.72 to 1.51) | 13.74 (10.69 to 17.39) | 0.44 (0.24 to 0.75) | ||
| Minor amputations | All | n (%, N) | 656 (1.8, 36 577) | 33 (0.0, 182 617) | 462 (2.3, 20 010) | 27 (0.0, 99 879) | 194 (1.2, 16 567) | 6 (0.0, 82 738) |
| Event rate (95% CI) | 1.92 (1.78 to 2.08) | 0.02 (0.01 to 0.03) | 2.50 (2.28 to 2.74) | 0.03 (0.02 to 0.04) | 1.24 (1.07 to 1.42) | 0.01 (0.00 to 0.02) | ||
| 18–49 years | n (%, N) | 308 (1.0, 29 578) | 9 (0.0, 147 804) | 208 (1.3, 16 305) | 9 (0.0, 81 463) | 100 (0.8, 13 273) | 0 (0.0, 66 341) | |
| Event rate (95% CI) | 1.11 (0.99 to 1.24) | 0.01 (0.00 to 0.01) | 1.37 (1.19 to 1.57) | 0.01 (0.01 to 0.02) | 0.79 (0.65 to 0.97) | 0.00 (0.00 to 0.01) | ||
| 50–64 years | n (%, N) | 276 (5.0, 5533) | 12 (0.0, 27 588) | 208 (7.0, 2968) | 8 (0.1, 14 792) | 68 (2.7, 2565) | 4 (0.0, 12 796) | |
| Event rate (95% CI) | 5.12 (4.54 to 5.76) | 0.04 (0.02 to 0.07) | 7.37 (6.40 to 8.44) | 0.05 (0.02 to 0.10) | 2.65 (2.06 to 3.36) | 0.03 (0.01 to 0.07) | ||
| 65+ years | n (%, N) | 72 (4.9, 1466) | 12 (0.2, 7225) | 46 (6.2, 737) | 10 (0.3, 3624) | 26 (3.6, 729) | 2 (0.1, 3601) | |
| Event rate (95% CI) | 7.29 (5.71 to 9.19) | 0.20 (0.10 to 0.35) | 9.63 (7.05 to 12.85) | 0.34 (0.16 to 0.63) | 5.10 (3.33 to 7.48) | 0.06 (0.01 to 0.23) | ||
| Major amputations | All | n (%, N) | 638 (1.7, 36 577) | 87 (0.0, 182 617) | 405 (2.0, 20 010) | 56 (0.1, 99 879) | 233 (1.4, 16 567) | 31 (0.0, 82 738) |
| Event rate (95% CI) | 1.87 (1.72 to 2.02) | 0.05 (0.04 to 0.06) | 2.19 (1.98 to 2.41) | 0.06 (0.04 to 0.08) | 1.49 (1.30 to 1.69) | 0.04 (0.03 to 0.05) | ||
| 18–49 years | n (%, N) | 209 (0.7, 29 578) | 22 (0.0, 147 804) | 124 (0.8, 16 305) | 14 (0.0, 81 463) | 85 (0.6, 13 273) | 8 (0.0, 66 341) | |
| Event rate (95% CI) | 0.75 (0.65 to 0.86) | 0.02 (0.01 to 0.02) | 0.82 (0.68 to 0.97) | 0.02 (0.01 to 0.03) | 0.67 (0.54 to 0.83) | 0.01 (0.01 to 0.02) | ||
| 50–64 years | n (%, N) | 295 (5.3, 5533) | 30 (0.1, 27 588) | 198 (6.7, 2968) | 19 (0.1, 14 792) | 97 (3.8, 2565) | 11 (0.1, 12 796) | |
| Event rate (95% CI) | 5.45 (4.85 to 6.11) | 0.10 (0.07 to 0.14) | 6.96 (6.02 to 8.00) | 0.12 (0.07 to 0.19) | 3.78 (3.07 to 4.62) | 0.08 (0.04 to 0.14) | ||
| 65+ years | n (%, N) | 134 (9.1, 1466) | 35 (0.5, 7225) | 83 (11.3, 737) | 23 (0.6, 3624) | 51 (7.0, 729) | 12 (0.3, 3601) | |
| Event rate (95% CI) | 13.74 (11.51 to 16.28) | 0.58 (0.40 to 0.80) | 17.75 (14.14 to 22.01) | 0.79 (0.50 to 1.18) | 10.05 (7.48 to 13.21) | 0.38 (0.20 to 0.67) | ||
Event rates are expressed per 1000 patient-years.