Skip to main content

Table 1 Demographic and other cohort characteristics

From: Sjogren’s syndrome is associated with higher rate of non-home discharge after primary hip arthroplasty and higher transfusion rates after primary hip or knee arthroplasty: a U.S. cohort study

  Primary TKA Primary THA
Entire cohort No Sjogren’s Syndrome Sjogren’s Syndrome Entire cohort No Sjogren’s Syndrome Sjogren’s Syndrome
National Projectionsa N = 8,127,282a N = 8,114,510a N = 12,772a N = 4,116,485a N = 4,110,263a N = 6222a
Age, Mean (SE); median 66.4 (0.03); 66.5 66.6 (0.02); 66.5 65.0 (0.20); 64.7 65.2 (0.04); 65.9 65.5 (0.04); 66.0 65.7 (0.32); 65.4
Age category
  < 50 430,141 (5.3%) 429,384 (5.3%) 757 (5.9%) 449,642 (10.9%) 449,170 (10.9%) 472 (7.6%)
 50–64 2,872,619 (35.3%) 2,867,321 (35.3%) 5298 (41.5%) 1,364,821 (33.2%) 1,362,528 (33.1%) 2293 (36.9%)
 65–79 3,969,942 (48.8%) 3,963,938 (48.8%) 6004 (47.0%) 1,732,015 (42.1%) 1,729,250 (42.1%) 2765 (44.4%)
  ≥ 80 850,131 (10.5%) 849,418 (10.5%) 713 (5.6%) 566,521 (13.8%) 565,828 (13.8%) 693 (11.1%)
Gender
 Female 5,126,809 (63.1%) 5,114,641 (63.0%) 12,168 (95.3%) 2,330,188 (56.6%) 2,324,441 (56.6%) 5747 (92.4%)
 Male 2,985,796 (36.7%) 2,985,197 (36.8%) 599 (4.7%) 1,776,722 (43.2%) 1,776,247 (43.2%) 475 (7.6%)
Race
 White 5,507,281 (67.8%) 5,497,996 (67.8%) 9285 (72.7%) 2,882,041 (70.0%) 2,877,245 (70.0%) 4796 (77.1%)
 Black 472,393 (5.8%) 471,784 (5.8%) 609 (4.8%) 225,772 (5.5%) 225,579 (5.5%) 193 (3.1%)
 Hispanic 340,292 (4.2%) 339,802 (4.2%) 490 (3.8%) 104,384 (2.5%) 104,234 (2.5%) 150 (2.4%)
 Other/Missing 1,807,101 (22.2%) 1,804,713 (22.2%) 2388 (18.7%) 904,234 (22.0%) 903,151 (22.0%) 1083 (17.4%)
Deyo-Charlson Score
 0 4,104,090 (50.5%) 4,100,452 (50.5%) 3638 (28.5%) 2,193,574 (53.3%) 2,191,576 (53.3%) 1998 (32.1%)
 1 2,064,888 (25.4%) 2,060,861 (25.4%) 4027 (31.5%) 926,286 (22.5%) 924,372 (22.5%) 1914 (30.8%)
  ≥ 2 1,958,305 (24.1%) 1,953,198 (24.1%) 5107 (40.0%) 996,623 (24.2%) 994,314 (24.2%) 2309 (37.1%)
Primary Diagnosis
 Rheumatoid arthritis 64,126 (0.8%) 63,422 (0.8%) 704 (5.5%) 29,173 (0.7%) 28,938 (0.7%) 235 (3.8%)
 Aseptic bone necrosis 21,031 (0.3%) 20,963 (0.3%) 68 (0.5%) 285,623 (6.9%) 284,864 (6.9%) 759 (12.2%)
 Osteoarthritis 7,866,436 (96.8%) 7,854,625 (96.8%) 11,811 (92.5%) 3,447,224 (83.7%) 3,442,590 (83.8%) 4634 (74.5%)
 Other 173,672 (2.1%) 173,488 (2.1%) 184 (1.4%) 354,307 (8.6%) 353,713 (8.6%) 594 (9.5%)
 Fracture 1904 (0.0%) 1904 (0.0%) 0 (0.0%) 117 (0.0%) 117 (0.0%) 0 (0.0%)
Hospital Location/Teaching
 Rural 1,041,159 (12.8%) 1,040,000 (12.8%) 1159 (9.1%) 444,188 (10.8%) 443,736 (10.8%) 452 (7.3%)
 Urban 3,665,766 (45.1%) 3,660,404 (45.1%) 5362 (42.0%) 1,722,391 (41.8%) 1,719,952 (41.8%) 2439 (39.2%)
 Urban Teaching 3,398,114 (41.8%) 3,391,899 (41.8%) 6215 (48.7%) 1,939,989 (47.1%) 1,936,692 (47.1%) 3297 (53.0%)
Insurance
 Medicaid 226,917 (2.8%) 226,680 (2.8%) 237 (1.9%) 138,809 (3.4%) 138,668 (3.4%) 141 (2.3%)
 Medicare 4,631,192 (57.0%) 4,623,773 (57.0%) 7419 (58.1%) 2,234,674 (54.3%) 2,230,839 (54.3%) 3835 (61.6%)
 Other 267,624 (3.3%) 267,297 (3.3%) 327 (2.6%) 102,277 (2.5%) 102,205 (2.5%) 72 (1.2%)
 Private 2,947,676 (36.3%) 2,942,954 (36.3%) 4722 (37.0%) 1,600,830 (38.9%) 1,598,692 (38.9%) 2138 (34.4%)
 Self 36,589 (0.5%) 36,535 (0.5%) 54 (0.4%) 32,307 (0.8%) 32,288 (0.8%) 19 (0.3%)
Income Category
 0-25th percentile 1,511,693 (18.6%) 1,509,616 (18.6%) 2077 (16.3%) 653,243 (15.9%) 652,323 (15.9%) 920 (14.8%)
 25-50th percentile 2,156,222 (26.5%) 2,153,260 (26.5%) 2962 (23.2%) 1,009,677 (24.5%) 1,008,178 (24.5%) 1499 (24.1%)
 50-75th percentile 2,158,012 (26.6%) 2,154,363 (26.5%) 3649 (28.6%) 1,086,953 (26.4%) 1,085,319 (26.4%) 1634 (26.3%)
 75-100th percentile 2,151,430 (26.5%) 2,147,588 (26.5%) 3842 (30.1%) 1,285,854 (31.2%) 1,283,805 (31.2%) 2049 (32.9%)
Hospital Bed size
 Small 1,408,128 (17.3%) 1,405,774 (17.3%) 2354 (18.4%) 685,209 (16.6%) 684,163 (16.6%) 1046 (16.8%)
 Medium 2,107,249 (25.9%) 2,103,919 (25.9%) 3330 (26.1%) 1,037,561 (25.2%) 1,036,014 (25.2%) 1547 (24.9%)
 Large 4,589,661 (56.5%) 4,582,609 (56.5%) 7052 (55.2%) 2,383,797 (57.9%) 2,380,202 (57.9%) 3595 (57.8%)
Hospital Region
 Northeast 1,359,230 (16.7%) 1,357,194 (16.7%) 2036 (15.9%) 818,699 (19.9%) 817,401 (19.9%) 1298 (20.9%)
 Midwest 2,269,799 (27.9%) 2,266,484 (27.9%) 3315 (26.0%) 1,089,883 (26.5%) 1,088,481 (26.5%) 1402 (22.5%)
 South 2,957,629 (36.4%) 2,953,077 (36.4%) 4552 (35.6%) 1,358,856 (33.0%) 1,356,707 (33.0%) 2149 (34.5%)
 West 1,540,624 (19.0%) 1,537,755 (19.0%) 2869 (22.5%) 849,045 (20.6%) 847,673 (20.6%) 1372 (22.1%)
In-hospital Complications and Healthcare Utilization
Transfusion 1,288,545 (15.9%) 1,286,034 (15.8%) 2511 (19.7%) 937,802 (22.8%) 935,821 (22.8%) 1981 (31.8%)
Implant Infection 8165 (0.1%) 8151 (0.1%) 14 (0.1%) 7592 (0.2%) 7573 (0.2%) 19 (0.3%)
Implant Revision 15,310 (0.2%) 15,281 (0.2%) 29 (0.2%) 17,931 (0.4%) 17,884 (0.4%) 47 (0.8%)
Death 7875 (0.1%) 7865 (0.1%) 10 (0.1%) 8889 (0.2%) 8880 (0.2%) 9 (0.2%)
Discharge Status
 Home 4,965,279 (61.1%) 4,957,619 (61.1%) 7660 (60.0%) 2,448,107 (59.5%) 2,444,859 (59.5%) 3248 (52.2%)
 Rehabilitation/inpatient facility 3,130,288 (38.5%) 3,125,196 (38.5%) 5092 (39.9%) 1,649,103 (40.1%) 1,646,152 (40.0%) 2951 (47.4%)
Hospital stay in days: Mean (SE); median 3.53 (0.01); 2.70 3.54 (0.01); 2.70 3.48 (0.03); 2.68 3.71 (0.01); 2.74 3.73 (0.01); 2.75 3.76 (0.06); 2.77
Hospital stay in days
  ≤ 3 5,218,769 (64.2%) 5,210,306 (64.2%) 8463 (66.3%) 2,499,883 (60.7%) 2,496,141 (60.7%) 3742 (60.1%)
  > 3 2,908,513 (35.8%) 2,904,204 (35.8%) 4309 (33.7%) 1,616,602 (39.3%) 1,614,122 (39.3%) 2480 (39.9%)
Total Hospital Charges, in U.S. $, Mean (SE); Median 42,336 (235); 35,891 42,441 (236); 35,946 46,429 (646); 39,793 44,635 (268); 37,658 44,859 (270); 37,785 50,084 (980);
42,495
  1. aU.S. National estimates were based on the following actual counts in the NIS, which is a 20% sample of all U.S. hospitalizations (https://www.hcup-us.ahrq.gov/nisoverview.jsp): TKA,N = 1,690,531; No Sjogren’s syndrome, N = 1,687,895; Sjogren’s syndrome, N = 2636; THA, N = 855,634; No Sjogren’s syndrome, N = 854,353; Sjogren’s syndrome, N = 1281; N (%), unless specified otherwise
  2. Overall, 12,772 (0.2%) of people with TKA hospitalizations had Sjogren’s Syndrome; 6222 (0.2%) of people with THA hospitalizations had Sjogren’s Syndrome
\