Table 1.
Baseline characteristics of the UK Biobank analytic sample, by study outcome
| Characteristic* | Not admitted and alive | Admitted or died | Lost to follow‐up | |
|---|---|---|---|---|
| Age (years) at baseline (median, interquartile range q25, q75) | 57 (50, 63) | 60 (53, 65) | 61 (52.5, 65) | |
| Age (years) at baseline | 38–44 | 44,062 (10.98) | 6909 (7.35) | 2 (1.96) |
| category (N [%]) | 45–54 | 118,684 (29.57) | 21,766 (23.14) | 26 (25.49) |
| 55–64 | 168,911 (42.09) | 40,541 (43.11) | 46 (45.10) | |
| 65–74 | 69,659 (17.36) | 24,831 (26.40) | 28 (27.45) | |
| Sex (N [%]) | Female | 223,144 (55.60) | 46,637 (49.59) | 68 (66.67) |
| Male | 178,172 (44.40) | 47,410 (50.41) | 34 (33.33) | |
| Townsend deprivation index | 1 (least deprived) | 83,464 (20.80) | 16,194 (17.22) | 24 (23.53) |
| fifths (N [%]) | 2 | 82,250 (20.50) | 17,010 (18.09) | 20 (19.61) |
| 3 | 81,280 (20.25) | 18,072 (19.22) | 24 (23.53) | |
| 4 | 79,803 (19.89) | 19,253 (20.47) | 14 (13.73) | |
| 5 (most deprived) | 74,519 (18.57) | 23,518 (25.01) | 20 (19.61) | |
| BMI (kg/m2) (mean [standard deviation]) | 27.2 (4.64) | 28.4 (5.32) | 27.6 (5.22) | |
| BMI category (kg/m2) | ≤25 | 138,608 (34.54) | 25,273 (26.87) | 36 (35.29) |
| (N [%]) | 25–30 | 171,477 (42.73) | 38,963 (41.43) | 39 (38.24) |
| >30 | 91,231 (22.73) | 29,811 (31.70) | 27 (26.47) | |
| Smoking status (N [%]) | Never | 225,899 (56.29) | 45,302 (48.17) | 63 (61.76) |
| Previous | 136,385 (33.98) | 35,509 (37.76) | 32 (31.37) | |
| Current | 39,032 (9.73) | 13,236 (14.07) | 7 (6.86) | |
| Alcohol use (N [%]) | Current | 372,194 (92.74) | 83,573 (88.86) | 90 (88.24) |
| Never | 16,546 (4.12) | 5317 (5.65) | 10 (9.8) | |
| Previous | 12,576 (3.13) | 5157 (5.48) | 2 (1.96) | |
| CI score (N [%]) | 0 | 342,977 (85.46) | 67,911 (72.21) | 74 (72.55) |
| 1 | 25,564 (6.37) | 12,386 (13.17) | 10 (9.80) | |
| 2 | 29,748 (7.41) | 11,137 (11.84) | 16 (15.69) | |
| 3+ | 3027 (0.75) | 2613 (2.78) | 2 (1.96) | |
| BI score (N [%]) | 0 | 297,207 (74.06) | 54,178 (57.61) | 61 (59.80) |
| 1 | 63,399 (15.8) | 21,401 (22.76) | 22 (21.57) | |
| 2 | 32,331 (8.06) | 12,937 (13.76) | 16 (15.69) | |
| 3+ | 8379 (2.09) | 5531 (5.88) | 3 (2.94) | |
| CC score (N [%]) | 0 | 149,170 (37.17) | 20,291 (21.58) | 34 (33.33) |
| 1 | 134,510 (33.52) | 27,878 (29.64) | 33 (32.35) | |
| 2 | 72,632 (18.1) | 21,967 (23.36) | 16 (15.69) | |
| 3+ | 45,004 (11.21) | 23,911 (25.42) | 19 (18.63) | |
| BC score (N [%]) | 0 | 107,386 (26.76) | 13,505 (14.36) | 20 (19.61) |
| 1 | 130,924 (32.62) | 25,522 (27.14) | 32 (31.37) | |
| 2 | 90,087 (22.45) | 24,692 (26.25) | 27 (26.47) | |
| 3+ | 72,919 (18.17) | 30,328 (32.25) | 23 (22.55) | |
| Proportion with multiple long‐term conditions (N [%])a | CI | 4760 (1.19) | 4422 (4.7) | 4 (3.92) |
| BI | 17,025 (4.24) | 11,097 (11.80) | 5 (4.90) | |
| CC | 117,636 (29.31) | 45,878 (48.78) | 35 (34.31) | |
| BC | 163,006 (40.62) | 55,020 (58.50) | 50 (49.02) | |
Note: N = 495,465.
Abbreviations: BC, body system count; BI, Byles index; BMI, body mass index; CC, condition count; CI, Charlson index.
a
Defined as having two or more items in each approach.
*
P‐value for differences between participants compare those with and without admission (or death) all <0.001, analysed using chi‐squared tests for categorical variables and Wilcoxon rank sum tests for continuous variables.