Table 1 Baseline demographic factors and comorbidity of study participants according to IDA
IDA Group | Non-IDA Group | p-value | |
|---|---|---|---|
N = 19,397 | N = 38,794 | ||
Age | 49.08 (17.54) | 49.08 (17.54) | 0.999 |
≦ 50 | 12,024 (61.99) | 24,069 (62.04) | |
>  50 | 7373 (38.01) | 14,725 (37.96) | |
Gender | 1.000 | ||
 Female | 14,891 (76.77) | 29,782 (76.77) | |
 Male | 4506 (23.23) | 9012 (23.23) | |
Income level | <  0.001 | ||
 Low | 9366 (48.29) | 19,247 (49.61) | |
 Intermediate | 8604 (44.36) | 16,523 (42.59) | |
 High | 1427 (7.36) | 3024 (7.80) | |
Comorbidity | |||
 Hypertension | 4991 (25.73) | 7874 (20.30) | <  0.001 |
 DM | 2719 (14.02) | 3529 (9.10) | <  0.001 |
 Dyslipidemia | 2822 (14.55) | 4435 (11.43) | <  0.001 |
 Hyperthyroidism | 551 (2.84) | 752 (1.94) | <  0.001 |
 Hypothyroidism | 199 (1.03) | 257 (0.66) | <  0.001 |
 COPD | 3618 (18.65) | 5606 (14.45) | <  0.001 |
 Stroke | 1642 (8.47) | 2235 (5.76) | <  0.001 |
 CAD | 2490 (12.84) | 3594 (9.26) | <  0.001 |
 CKD | 888 (4.58) | 412 (1.06) | <  0.001 |
 Cirrhosis | 566 (2.92) | 216 (0.56) | <  0.001 |
 Iron supplementation | 12,450 (64.19) | 1551 (4.00) | <  0.001 |
Area | <  0.001 | ||
 Urban | 11,393 (58.74) | 23,754 (61.23) | |
 Suburban | 5974 (30.80) | 11,479 (29.59) | |
 Rural | 1286 (6.63) | 2216 (5.71) | |
 Remote area | 744 (3.84) | 1345 (3.47) | |