Table 1.
Baseline characteristics of patients with type 2 diabetes mellitus in the UK Biobank
| Characteristics | Total (n=19 360) |
Social isolation | Loneliness | |||
| Least social isolation (n=7409) |
Moderate social isolation (n=8147) |
Most social isolation (n=3804) |
No loneliness (n=17 873) |
Loneliness (n=1487) |
||
| Age, mean (SD), years | 59.4 (7.0) | 60.0 (6.9) | 59.3 (7.1) | 58.6 (7.1) | 59.6 (7.0) | 58.0 (7.2) |
| Gender, male, n (%) | 11 820 (61.1) | 4594 (62.0) | 4811 (59.1) | 2415 (63.5) | 10 884 (60.9) | 936 (62.9) |
| Ethnicity, white, n (%) | 17 057 (88.1) | 6587 (88.9) | 7162 (87.9) | 3308 (87.0) | 15 746 (88.1) | 1311 (88.2) |
| Assessment centre, n (%) | ||||||
| England | 17 237 (89.0) | 6549 (88.4) | 7295 (89.5) | 3393 (89.2) | 15 925 (89.1) | 1312 (88.2) |
| Scotland | 1233 (6.4) | 481 (6.5) | 495 (6.1) | 257 (6.8) | 1124 (6.3) | 109 (7.3) |
| Wales | 890 (4.6) | 379 (5.1) | 357 (4.4) | 154 (4.0) | 824 (4.6) | 66 (4.4) |
| Currently employed, n (%) | 8545 (44.1) | 3135 (42.3) | 3680 (45.2) | 1730 (45.5) | 7937 (44.4) | 608 (40.9) |
| College or university degree, n (%) | 4776 (24.7) | 1888 (25.5) | 1945 (23.9) | 943 (24.8) | 4485 (25.1) | 291 (19.6) |
| Townsend Deprivation Index* | −0.5 (3.4) | −1.2 (3.1) | −0.4 (3.4) | 0.5 (3.6) | −0.6 (3.3) | 0.4 (3.6) |
| Current smokers, n (%) | 2228 (11.5) | 638 (8.6) | 946 (11.6) | 644 (16.9) | 1974 (11.0) | 254 (17.1) |
| Alcohol consumption status, n (%) | ||||||
| Not current | 2867 (14.8) | 935 (12.6) | 1222 (15.0) | 710 (18.7) | 2572 (14.4) | 295 (19.8) |
| Less than three times a week | 10 545 (54.5) | 3770 (50.9) | 4552 (55.9) | 2223 (58.4) | 9713 (54.3) | 832 (56.0) |
| Three or more times a week | 5948 (30.7) | 2704 (36.5) | 2373 (29.1) | 871 (22.9) | 5588 (31.3) | 360 (24.2) |
| Physical activity (MET score), mean (SD) | 9.6 (5.1) | 10.3 (4.9) | 9.5 (5.1) | 8.8 (5.2) | 9.7 (5.0) | 8.7 (5.3) |
| TV watching time (hours/day), mean (SD) | 3.4 (2.0) | 3.3 (1.7) | 3.5 (1.9) | 3.8 (2.4) | 3.4 (1.9) | 4.0 (2.5) |
| Healthy diet score, median (IQR) | 3 (2–4) | 3 (2–4) | 3 (2–4) | 3 (2–3) | 3 (2–4) | 2 (2–3) |
| Sleep duration, n (%) | ||||||
| Short (<7 hours/day) | 5382 (27.8) | 1754 (23.7) | 2326 (28.6) | 1302 (34.2) | 4771 (26.7) | 611 (41.1) |
| Normal (7–8 hours/day) | 11 719 (60.5) | 4746 (64.1) | 4893 (60.1) | 2080 (54.7) | 11 043 (61.8) | 676 (45.5) |
| Long (>8 hours/day) | 2259 (11.7) | 909 (12.3) | 928 (11.4) | 422 (11.1) | 2059 (11.5) | 200 (13.4) |
| Anxiety, n (%) | 89 (0.5) | 24 (0.3) | 43 (0.5) | 22 (0.6) | 78 (0.4) | 11 (0.7) |
| Depression, n (%) | 296 (1.5) | 66 (0.9) | 135 (1.7) | 95 (2.5) | 240 (1.3) | 56 (3.8) |
| Ever seeking help from physicians due to anxiety or depressive symptoms, n (%) | 6797 (35.1) | 2298 (31.0) | 2954 (36.3) | 1545 (40.6) | 5982 (33.5) | 815 (54.8) |
| Obesity status (kg/m2) | ||||||
| Underweight or normal weight, n (%) | 1893 (9.8) | 713 (9.6) | 812 (10.0) | 368 (9.7) | 1776 (9.9) | 117 (7.9) |
| Overweight, n (%) | 6548 (33.8) | 2697 (36.4) | 2702 (33.2) | 1149 (30.2) | 6141 (34.4) | 407 (27.4) |
| Obese, n (%) | 10 919 (56.4) | 3999 (54.0) | 4633 (56.9) | 2287 (60.1) | 9956 (55.7) | 963 (64.8) |
| Grip strength (kg), mean (SD) | 30.6 (11.1) | 31.1 (11.1) | 30.4 (11.0) | 30.1 (11.0) | 30.7 (11.0) | 29.6 (11.2) |
| Systolic blood pressure (mm Hg), mean (SD) | 145 (18) | 145 (18) | 145 (18) | 144 (19) | 145 (19) | 142 (18) |
| Diastolic blood pressure (mm Hg), mean (SD) | 83 (10) | 83 (10) | 83 (10) | 83 (11) | 83 (10) | 83 (10) |
| Hyperlipidaemia, n (%) | 13 265 (68.5) | 5129 (69.2) | 5558 (68.2) | 2578 (67.8) | 12 217 (68.4) | 1048 (70.5) |
| Estimated glomerular filtration rate, mean (SD), mL/min/1.73 m2 | 89.8 (15.6) | 89.5 (15.1) | 90.0 (15.7) | 90.3 (16.2) | 89.7 (15.5) | 91.2 (16.3) |
| Family history of diabetes, n (%) | 7061 (36.5) | 2690 (36.3) | 3034 (37.2) | 1337 (35.1) | 6484 (36.3) | 577 (38.8) |
| HbA1c, median (IQR), % | 6.8 (6.2–7.5) | 6.7 (6.1–7.4) | 6.8 (6.2–7.5) | 6.8 (6.2–7.7) | 6.7 (6.2–7.5) | 6.9 (6.2–7.7) |
| Diabetes duration, median (IQR), years | 4.0 (1.0–8.0) | 4.0 (1.0–8.0) | 4.0 (1.0–8.0) | 4.0 (1.0–8.0) | 4.0 (1.0–8.0) | 4.1 (1.0–9.0) |
| Diabetes medication use, n (%) | ||||||
| Neither | 7227 (37.3) | 2877 (38.8) | 3007 (36.9) | 1343 (35.3) | 6752 (37.8) | 475 (31.9) |
| Oral antidiabetic drug only | 9584 (49.5) | 3628 (49.0) | 4036 (49.5) | 1920 (50.5) | 8822 (49.4) | 762 (51.2) |
| Insulin | 2549 (13.2) | 904 (12.2) | 1104 (13.6) | 541 (14.2) | 2299 (12.9) | 250 (16.8) |
| Chronic kidney disease, n (%) | 328 (1.7) | 107 (1.4) | 141 (1.7) | 80 (2.1) | 298 (1.7) | 30 (2.0) |
| Diabetes-related microvascular disease, n (%) | 321 (1.7) | 102 (1.4) | 145 (1.8) | 74 (1.9) | 290 (1.6) | 31 (2.1) |
| Neurodegenerative disease, n (%) | 52 (0.3) | 15 (0.2) | 19 (0.2) | 18 (0.5) | 43 (0.2) | 9 (0.6) |
| Respiratory disease, n (%) | 717 (3.7) | 227 (3.1) | 301 (3.7) | 189 (5.0) | 627 (3.5) | 90 (6.1) |
| Digestive disease, n (%) | 269 (1.4) | 78 (1.1) | 118 (1.4) | 73 (1.9) | 243 (1.4) | 26 (1.7) |
| Rheumatoid arthritis, n (%) | 318 (1.6) | 124 (1.7) | 135 (1.7) | 59 (1.6) | 289 (1.6) | 29 (2.0) |
| Osteoarthritis, n (%) | 2130 (11.0) | 774 (10.4) | 882 (10.8) | 474 (12.5) | 1927 (10.8) | 203 (13.7) |
*Positive values of the index indicate areas with high material deprivation, whereas those with negative values indicate relative affluence.
HbA1c, haemoglobin A1c; IQR, interquartile range; MET, metabolic equivalent of task; SD, standard deviation.