Table 1.
Participants' characteristics by their type 2 diabetes mellitus status
| Participants’ characteristics | No. cases | No T2DM n = 473 (93.1%) | T2DM n = 35 (6.9%) | P-value |
|---|---|---|---|---|
| Age, mean (SD) | 505 | 35.27 (14.87) | 51.09 (13.26) | <0.001 |
| Gender: male, n (%) | 508 | 158 (33.4) | 25 (71.4) | <0.001 |
| Ethnicity: Bulgarian, n (%) | 507 | 403 (85.4) | 31 (88.6) | 0.804 |
| Education, n (%) | 508 | 0.148 | ||
| Basic | 5 (1.1) | 2 (5.7) | ||
| Upper secondary | 238 (50.3) | 18 (51.4) | ||
| Bachelor/master | 218 (46.1) | 14 (40.0) | ||
| PhD, DSc | 12 (2.5) | 1 (2.9) | ||
| Marital status, n (%) | 507 | 0.071 | ||
| Married/having a spouse | 292 (61.7) | 23 (67.6) | ||
| Single | 151 (31.9) | 6 (17.6) | ||
| Widowed | 9 (1.9) | 2 (5.9) | ||
| Divorced | 21 (4.4) | 3 (8.8) | ||
| Occupation, n (%) | 507 | <0.001 | ||
| Employed | 262 (55.5) | 21 (60.0) | ||
| Studying | 171 (36.2) | 2 (5.7) | ||
| Unemployed | 15 (3.2) | 3 (8.6) | ||
| Retired | 24 (5.1) | 9 (25.7) | ||
| Socioeconomic status, n (%) | 506 | 0.007 | ||
| Lower | 122 (25.9) | 16 (45.7) | ||
| Middle | 331 (70.3) | 16 (45.7) | ||
| Upper | 18 (3.8) | 3 (8.6) | ||
| BMI, mean (SD) | 502 | 22.98 (4.08) | 27.80 (4.95) | <0.001 |
| Sport activity, mean (SD) | 477 | 1.37 (2.35) | 0.30 (0.89) | <0.001 |
| Wholegrain meals, mean (SD) | 476 | 3.53 (3.07) | 2.77 (3.35) | 0.200 |
| Alcohol beverages, mean (SD) | 469 | 1.22 (1.58) | 1.60 (2.48) | 0.381 |
| Meat meals, mean (SD) | 481 | 4.16 (2.86) | 3.14 (1.07) | <0.001 |
| Soda beverages, mean (SD) | 468 | 1.63 (2.19) | 0.63 (1.31) | <0.001 |
| Sweet treats, mean (SD) | 475 | 3.48 (2.42) | 2.05 (2.44) | 0.002 |
| Pack years of smoking, mean (SD) | 500 | 5.09 (11.67) | 14.21 (18.66) | 0.009 |
| Family history of T2DM: Yes, n (%) | 496 | 139 (30.2) | 18 (51.4) | 0.013 |
| Years residential exposure to loud noise, mean (SD) | 497 | 2.70 (6.93) | 2.38 (7.87) | 0.815 |
| Years occupational exposure to loud noise, mean (SD) | 501 | 2.98 (7.23) | 8.93 (12.74) | 0.010 |
| Noise sensitivity, mean (SD) | 473 | 3.32 (0.76) | 3.57 (0.64) | 0.042 |
| Noise annoyance, mean (SD) | 504 | 5.50 (2.27) | 5.69 (1.43) | 0.477 |
| Sleep disturbance, mean (SD) | 505 | 3.97 (3.09) | 5.69 (2.26) | <0.001 |
| Self-reported traffic intensity, n (%) | 492 | 0.001 | ||
| Very rare/no traffic | 90 (19.5) | 7 (22.6) | ||
| Moderately busy street | 169 (36.7) | 2 (6.5) | ||
| Considerably busy street | 76 (16.5) | 5 (16.1) | ||
| Heavy traffic | 64 (13.9) | 8 (25.8) | ||
| Extremely busy street/extreme traffic | 62 (13.4) | 9 (29.0) | ||
| Perceived air quality, mean (SD) | 480 | 5.49 (2.10) | 5.56 (2.23) | 0.853 |
| Perceived severity of air pollution, mean (SD) | 481 | 5.71 (2.16) | 6.00 (2.16) | 0.475 |
| Air pollution annoyance, mean (SD) | 480 | 5.75 (2.29) | 6.53 (2.11) | 0.050 |
| Duration of residence, mean (SD) | 480 | 15.26 (13.67) | 26.82 (17.09) | 0.001 |
| Bedroom location: Noisy façade side, n (%) | 477 | 116 (26.0) | 16 (53.3) | 0.001 |
| Nights with open bedroom windows, mean (SD) | 460 | 5.68 (2.27) | 6.05 (1.83) | 0.286 |
| Lden [dB], n (%) | 299 | <0.001 | ||
| 51-55 | 18 (6.4) | 0 (0.0) | ||
| 56-60 | 23 (8.2) | 3 (15.8) | ||
| 61-65 | 60 (21.4) | 1 (5.3) | ||
| 66-70 | 93 (33.2) | 0 (0.0) | ||
| 71-75 | 80 (26.8) | 13 (68.4) | ||
| 76-80 | 6 (2.1) | 2 (10.5) | ||
| >80 | 0 (0.0) | 0 (0.0) | ||
| PM2.5 [μg/m3], n (%) | 330 | 0.267 | ||
| 0.0-17.5 | 2 (0.6) | 0 (0.0) | ||
| 17.5-20.3 | 38 (12.3) | 3 (13.6) | ||
| 20.3-25.0 | 41 (13.3) | 1 (4.5) | ||
| 25.0-40.0 | 127 (41.2) | 6 (27.3) | ||
| 40.0-66.8 | 100 (32.5) | 12 (54.5) | ||
| BaP [ng/m3], n (%) | 330 | 0.961 | ||
| 0.0-1.0 | 1 (0.3) | 0 (0.0) | ||
| 1.0-3.75 | 56 (18.2) | 3 (13.6) | ||
| 3.75-6.0 | 86 (27.9) | 6 (27.3) | ||
| 6.0-9.75 | 164 (53.2) | 13 (59.1) | ||
| 9.75-14.02 | 1 (0.3) | 0 (0.0) |
Note. T2DM = Type 2 diabetes mellitus, BaP = Benzo alpha pyrene, PM2.5 = Particulate matter pollutants of ≤2.5 μm in aerodynamic diameter, Lden = Day-evening-night equivalent sound level, BMI = Body mass index, Percentages are reported within columns. Calculations are based on the valid number of cases in the original dataset (i.e., excluding cases with missing values on “type 2 diabetes status” and/or respective participants’ characteristics)