Table 1.
Characteristics and DED prevalence of the study population
| Characteristics | Number of subjects (%) | Number of patients with DED | DED prevalence (%) | Chi square | P value |
|---|---|---|---|---|---|
| Gender | 149.0810 | < 0.0001 | |||
| Male | 11,686 (48.85) | 6736 | 57.64 | ||
| Female | 12,236 (51.15) | 7993 | 65.32 | ||
| Age (years old) | 351.0333 | < 0.0001 | |||
| < 25 | 4969 (20.77) | 2579 | 51.90 | ||
| 25–45 | 10,895 (45.54) | 6648 | 61.02 | ||
| > 45 | 8058 (33.68) | 5502 | 68.28 | ||
| Keratorefractive surgery | 43.5570 | < 0.0001 | |||
| No | 20,330 (84.98) | 12,340 | 60.70 | ||
| Yes | 3592 (15.02) | 2389 | 66.51 | ||
| Diabetes | 32.7384 | < 0.0001 | |||
| No | 21,926 (91.66) | 13,381 | 61.03 | ||
| Yes | 1996 (8.34) | 1348 | 67.54 | ||
| Arthritis | 136.1486 | < 0.0001 | |||
| No | 22,003 (91.98) | 13,309 | 60.49 | ||
| Yes | 1919 (8.02) | 1420 | 74.00 | ||
| Thyroid diseases | 11.1371 | 0.0008 | |||
| No | 22,503 (94.07) | 13,796 | 61.31 | ||
| Yes | 1419 (5.93) | 933 | 65.75 | ||
| Antihistamine | 65.9711 | < 0.0001 | |||
| No | 22,414 (93.70) | 13,652 | 60.91 | ||
| Yes | 1508 (6.30) | 1077 | 71.42 | ||
| OC | 6.5310 | 0.0106 | |||
| No | 23,122 (96.66) | 14,271 | 61.72 | ||
| Yes | 800 (3.34) | 458 | 57.25 | ||
| Diuretics | 33.8723 | < 0.0001 | |||
| No | 22,921 (95.82) | 14,025 | 61.19 | ||
| Yes | 1001 (4.18) | 704 | 70.33 | ||
| DU drugs | 57.8380 | < 0.0001 | |||
| No | 23,361 (97.65) | 14,297 | 61.20 | ||
| Yes | 561 (2.35) | 432 | 77.01 | ||
| Diazepam | 72.7696 | < 0.0001 | |||
| No | 23,170 (96.86) | 14,154 | 61.09 | ||
| Yes | 752 (3.14) | 575 | 76.46 | ||
| CO (days)* | 6.3735 | 0.0116 | |||
| < 124 | 17,338 (72.48) | 10,760 | 62.06 | ||
| ≥ 124 | 6584 (27.52) | 3969 | 60.28 | ||
| NO2 (days)* | 2.9279 | 0.0871 | |||
| < 150 | 15,968 (66.75) | 9771 | 61.19 | ||
| ≥ 150 | 7954 (33.25) | 4958 | 62.33 | ||
| O3 (days)* | 1349.9078 | < 0.0001 | |||
| < 125 | 17,770 (74.28) | 9733 | 54.77 | ||
| ≥ 125 | 6152 (25.72) | 4996 | 81.21 | ||
| PM10 (days)* | 63.8984 | < 0.0001 | |||
| < 102 | 15,071 (63.00) | 8989 | 59.64 | ||
| ≥ 102 | 8851 (37.00) | 5740 | 64.85 | ||
| PM2.5 (days)* | 5.0322 | 0.0249 | |||
| < 143 | 17,195 (71.88) | 10,663 | 62.01 | ||
| ≥ 143 | 6727 (28.12) | 4066 | 60.44 | ||
| SO2 (days)* | 256.7553 | < 0.0001 | |||
| < 101 | 17,555 (73.38) | 10,276 | 58.54 | ||
| ≥ 101 | 6367 (26.62) | 4453 | 69.94 | ||
| Total | 23,922 (100.00) | 14,729 | 61.57 | – | – |
* The number of days in which the pollutant concentration exceeds the “extreme value”