TABLE 1.
Baseline Characteristics of the Study Sample of Adult Participants with Chronic Liver Disease by Hemochromatosis Status Before and After Matchinga
| Patient Characteristics | Unmatched | Matchedb | |||||
|---|---|---|---|---|---|---|---|
| Hemochromatosis (n = 37,237) | No Hemochromatosis (n = 580,659) | Standardized Differencec | Hemochromatosis (n = 37,092) | No Hemochromatosis (n = 37,092) | Standardized Differencec | ||
| Age, mean (SD) | 47.09 (11.32) | 48.82 (10.77) | 0.1574 | 47.09 (11.31) | 47.17 (11.27) | 0.0065 | |
| Age group, years, n (%) | 0.1506 | 0.0069 | |||||
| 18-34 | 5,623 (15.1) | 68,387 (11.8) | 5,592 (15.1) | 5,504 (14.8) | |||
| 35-44 | 7,856 (21.1) | 108,384 (18.7) | 7,827 (21.1) | 7,835 (21.1) | |||
| 45-54 | 12,251 (32.9) | 188,462 (32.5) | 12,204 (32.9) | 12,224 (33.0) | |||
| 55+ | 11,507 (30.9) | 215,426 (37.1) | 11,469 (30.9) | 11,529 (31.1) | |||
| Gender, n (%) | 0.0179 | 0.0023 | |||||
| Male | 17,337 (46.6) | 275,530 (47.5) | 17,271 (46.6) | 17,228 (46.5) | |||
| Female | 19,900 (53.4) | 305,129 (52.6) | 19,821 (53.4) | 19,864 (53.6) | |||
| Region of residence, n (%) | 0.1417 | 0.0055 | |||||
| Northeast | 9,329 (25.1) | 126,950 (21.7) | 9,285 (25.0) | 9,290 (25.1) | |||
| North Central | 7,325 (19.7) | 103,548 (17.8) | 7,296 (19.7) | 7,301 (19.7) | |||
| South | 12,229 (32.8) | 229,570 (39.5) | 12,180 (32.8) | 12,225 (330) | |||
| West | 7,542 (20.3) | 109,865 (18.9) | 7,523 (20.3) | 7,494 (20.2) | |||
| Unknown | 812 (2.2) | 10,726 (1.9) | 808 (2.2) | 782 (2.1) | |||
| Type of health insurance, n (%) | 0.1113 | 0.0155 | |||||
| Unknown | 1,277 (3.4) | 20,366 (3.5) | 1,265 (3.4) | 1,247 (3.36) | |||
| Comprehensive | 779 (2.1) | 16,647 (2.8) | 773 (2.1) | 767 (2.1) | |||
| Exclusive provider organization | 764 (2.1) | 9,871 (1.7) | 759 (2.1) | 746 (2.0) | |||
| Health maintenance organization | 3,881 (10.4) | 75,695 (13.0) | 3,855 (10.4) | 3,886 (10.5) | |||
| Non-capitated point-of-service | 2,869 (7.7) | 44,680 (7.7) | 2,861 (7.7) | 2,829 (7.6) | |||
| Preferred provider organization | 23,815 (64.0) | 354,427 (61.0) | 23,752 (64.0) | 23,859 (64.3) | |||
| Point-of-service with capitation | 169 (0.5) | 2,503 (0.4) | 169 (0.5) | 140 (0.4) | |||
| Consumer-driven health plan | 2,182 (5.9) | 37,395 (6.4) | 2,168 (5.8) | 2,179 (5.9) | |||
| High-deductible health plan | 1,501 (4.0) | 19,075 (3.3) | 1,490 (4.0) | 1,439 (3.9) | |||
| Comorbidity profiled | |||||||
| Charlson Comorbidity Index score, mean (SD) | 0.69 (1.36) | 1.12 (1.82) | 0.2658 | 0.69 (1.36) | 0.71 (1.46) | 0.0125 | |
| Charlson Comorbidity Index score, n (%) | 0.2975 | 0.0049 | |||||
| 0 | 24,372 (65.5) | 301,235 (51.9) | 24,281 (65.5) | 24,305 (65.5) | |||
| 1 | 7,033 (18.9) | 136,867 (23.6) | 6,999 (18.8) | 7,028 (19.0) | |||
| 2 | 2,848 (7.6) | 57,624 (9.9) | 2,838 (7.6) | 2,807 (7.6) | |||
| 3 | 1,423 (3.8) | 38,098 (6.6) | 1,418 (3.8) | 1,421 (3.8) | |||
| 4+ | 1,561 (4.2) | 46,835 (8.1) | 1,556 (4.2) | 1,531 (4.1) | |||
| Type 2 diabetes, n (%) | 5,453 (14.6) | 139,698 (24.1) | 0.2400 | 5,432 (14.6) | 5,452 (14.7) | 0.0015 | |
| Arthritis, n (%) | 15,483 (41.6) | 264,306 (45.5) | 0.0795 | 15,415 (41.6) | 15,430 (41.6) | 0.0008 | |
| Alcohol abuse or dependence, n (%) | 199 (0.5) | 7,970 (1.4) | 0.0863 | 198 (0.5) | 170 (0.5) | 0.0107 | |
| Myocardial infarction, n (%) | 280 (0.8) | 8,893 (1.5) | 0.0734 | 280 (0.8) | 255 (0.8) | 0.0080 | |
aAll demographics data were obtained on index date (first diagnosis date of hemochromatosis for cases and a randomly selected date from all claim records for controls).
bHemochromatosis cases and hemochromatosis-free controls were matched 1:1 using propensity score. The logistic regression model used to estimate propensity scores included age; region of residence; gender; type of health insurance; Charlson Comorbidity Index score (excluding myocardial infarction, rheumatic disease, diabetes without chronic complications, and diabetes with chronic complications); myocardial infarction; type 2 diabetes; arthritis; and alcohol abuse or dependence.
cDifference in means or proportions divided by standard error. Imbalance between the 2 groups was defined as absolute value greater than 0.10; smaller values indicated better balance.
dEstimated during the 12 months before the index date.
SD = standard deviation.