Volume 32, Number 6—June 2026
Research
Association of Frailty and Frailty Trajectory with Risk for Respiratory Infectious Diseases
Table 1
Baseline characteristics of participants in the first and final assessment of physical frailty in a study of association of frailty and frailty trajectory with risk for RIDs*
| Characteristics | First assessment |
Final assessment |
|||||||
|---|---|---|---|---|---|---|---|---|---|
| Frail, n = 9,075 | Prefrail, n = 144,734 |
Nonfrail, n = 269,882 |
p value† | Frail, n = 409 |
Prefrail, n = 8,350 |
Nonfrail, n = 8,089 |
p value† | ||
| Mean follow-up, y (SD) |
12.29 (3.34) |
13.02 (2.64) |
13.37 (2.25) |
<0.001 |
8.96 (2.33) |
9.50 (1.59) |
9.69 (1.44) |
<0.001 |
|
| Mean age, y (SD) |
57.86 (7.63) |
56.96 (8.08) |
55.97 (8.09) |
<0.001 |
62.40 (7.52) |
62.10 (7.29) |
60.36 (7.46) |
<0.001 |
|
| Sex | <0.001 | <0.001 | |||||||
| M | 3,327 (36.7) | 62,077 (42.9) | 127,389 (47.2) | 169 (41.3) | 3,950 (47.3) | 4,144 (51.2) | |||
| F |
5,748 (63.3) |
82,657 (57.1) |
142,493 (52.8) |
240 (58.7) |
4,400 (52.7) |
3,945 (48.8) |
|||
| Ethnicity | <0.001 | <0.001 | |||||||
| White | 7,793 (85.9) | 133,415 (92.2) | 259,028 (96.0) | 389 (95.1) | 8,122 (97.3) | 7,927 (98.0) | |||
| Another race |
1,282 (14.1) |
11,319 (7.8) |
10,854 (4.0) |
20 (4.9) |
228 (2.7) |
162 (2.0) |
|||
| Education | <0.001 | <0.001 | |||||||
| High | 1,398 (15.4) | 41,353 (28.6) | 99,556 (36.9) | 106 (25.9) | 3,505 (42.0) | 3,868 (47.8) | |||
| Intermediate | 4,061 (44.7) | 73,466 (50.8) | 135,111 (50.1) | 219 (53.5) | 4,056 (48.6) | 3,688 (45.6) | |||
| Low |
3,616 (39.8) |
29,915 (20.7) |
35,215 (13.0) |
84 (20.5) |
789 (9.4) |
533 (6.6) |
|||
| Smoking status | <0.001 | <0.001 | |||||||
| Never | 4,229 (46.6) | 76,799 (53.1) | 154,029 (57.1) | 209 (51.1) | 4,909 (58.8) | 4,944 (61.1) | |||
| Previous | 3,047 (33.6) | 50,681 (35.0) | 91,828 (34.0) | 156 (38.1) | 2,918 (34.9) | 2,676 (33.1) | |||
| Current |
1,799 (19.8) |
17,254 (11.9) |
24,025 (8.9) |
44 (10.8) |
523 (6.3) |
469 (5.8) |
|||
| Alcohol status | <0.001 | <0.001 | |||||||
| Never | 1,060 (11.7) | 8,211 (5.7) | 8,440 (3.1) | 30 (7.3) | 320 (3.8) | 220 (2.7) | |||
| Previous | 1,025 (11.3) | 6,629 (4.6) | 6,649 (2.5) | 37 (9.0) | 275 (3.3) | 184 (2.3) | |||
| Current |
6,990 (77.0) |
129,894 (89.7) |
254,793 (94.4) |
342 (83.6) |
7,755 (92.9) |
7,684 (95.0) |
|||
| Mean (SD) Townsend deprivation index |
0.74 (3.59) |
−0.93 (3.24) |
−1.66 (2.88) |
<0.001 |
−0.54 (3.44) |
−1.91 (2.75) |
−2.27 (2.53) |
<0.001 |
|
| Mean (SD) sleep duration, h/d |
6.81 (2.22) |
7.07 (1.37) |
7.15 (1.08) |
<0.001 |
6.97 (2.19) |
7.22 (1.16) |
7.21 (0.99) |
<0.001 |
|
| Mean (SD) cumulative dietary risk factor score |
5.29 (1.45) |
4.99 (1.42) |
4.91 (1.38) |
<0.001 |
5.29 (1.38) |
4.88 (1.33) |
4.87 (1.32) |
<0.001 |
|
| Mean (SD) PM2.5, μg/m3 |
10.34 (1.11) |
10.07 (1.06) |
9.93 (1.04) |
<0.001 |
10.26 (1.13) |
10.01 (1.06) |
9.92 (1.02) |
<0.001 |
|
| Mean (SD) NO2, μg/m3 |
29.28 (7.69) |
27.33 (7.64) |
26.23 (7.56) |
<0.001 |
28.02 (6.97) |
26.35 (6.92) |
25.71 (6.72) |
<0.001 |
|
| Mean (SD) NO, μg/m3 |
48.91 (16.56) |
45.24 (15.86) |
43.19 (15.28) |
<0.001 |
47.05 (14.94) |
43.78 (14.63) |
42.46 (13.87) |
<0.001 |
|
| BMI category‡ | <0.001 | <0.001 | |||||||
| Underweight | 62 (0.7) | 758 (0.5) | 1,184 (0.4) | 3 (0.7) | 36 (0.4) | 46 (0.6) | |||
| Normal weight | 1,369 (15.1) | 36,742 (25.4) | 100,907 (37.4) | 68 (16.8) | 2,577 (31.1) | 3,481 (43.6) | |||
| Overweight | 2,728 (30.1) | 60,162 (41.6) | 118,895 (44.1) | 131 (32.4) | 3,664 (44.2) | 3,369 (42.2) | |||
| Obese |
4,916 (54.2) |
47,072 (32.5) |
48,896 (18.1) |
202 (50.0) |
2,013 (24.3) |
1,096 (13.7) |
|||
| RIDs | <0.001 | <0.001 | |||||||
| N | 6,882 (75.8) | 125,900 (87.0) | 246,801 (91.4) | 337 (82.4) | 7,695 (92.2) | 7,627 (94.3) | |||
| Y | 2,193 (24.2) | 18,834 (13.0) | 23,081 (8.6) | 72 (17.6) | 655 (7.8) | 462 (5.7) | |||
*Values are no. (%) except as indicated. Data are from UK Biobank (https://www.ukbiobank.ac.uk) during 2006–2010 for the first assessment and during 2012–2013 for the final assessment. BMI, body mass index; PM2.5, particulate matter <2.5 mm; NO, nitrogen oxide; NO2, nitrogen dioxide; RIDs, respiratory infectious diseases. †Calculated by analysis of variance, Kruskal-Wallis H, or χ2 test. p<0.05 considered statistically significant. ‡Underweight <18.5 kg/m2; normal weight, 18.5 kg/m2 to <25 kg/m2; overweight, 25 kg/m2 to <30 kg/m2; obese, >30 kg/m2.
1These first authors contributed equally to this article.
Page created: April 22, 2026
Page updated: June 01, 2026
Page reviewed: June 01, 2026
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