Multivariable-adjusted association of SSc and other clinical variables with healthcare use outcomes and in-hospital implant infection, transfusion, revision, and mortality post-primary THA*.
| Variables | Total Hospital Charges above the Median** | Discharge to Non-home Settings | Length of Hospital Stay > 3 Days | In-hospital Implant Infection | In-hospital Transfusion | In-hospital Revision Surgery | In-hospital Mortality |
|---|---|---|---|---|---|---|---|
| SSc | 0.90 (0.76–1.07) | 1.25 (1.03–1.50) | 1.61 (1.35–1.92) | 0.93 (0.22–3.99) | 1.54 (1.28–1.84) | 9.53 (6.75–13.46) | 2.19 (0.99–4.86) |
| Age category, yrs | |||||||
| < 50 | Ref | Ref | Ref | Ref | Ref | Ref | Ref |
| 50–64 | 0.86 (0.82–0.90) | 1.75 (1.71–1.78) | 1.09 (1.08–1.11) | 0.97 (0.82–1.16) | 1.11 (1.09–1.13) | 0.96 (0.84–1.11) | 0.77 (0.71–0.83) |
| 65–79 | 0.88 (0.84–0.93) | 3.36 (3.28–3.44) | 1.37 (1.35–1.40) | 0.93 (0.74–1.15) | 1.30 (1.26–1.33) | 0.90 (0.76–1.07) | 0.90 (0.81–1.01) |
| ≥ 80 | 1.01 (0.95–1.07) | 10.75 (10.46–11.04) | 1.95 (1.90–1.99) | 0.94 (0.74–1.19) | 1.85 (1.80–1.90) | 0.92 (0.76–1.11) | 2.50 (2.24–2.80) |
| Sex | |||||||
| Male | Ref | Ref | Ref | Ref | Ref | Ref | Ref |
| Female | 0.97 (0.95–1.00) | 1.73 (1.71–1.75) | 1.20 (1.19–1.21) | 0.95 (0.87–1.04) | 1.68 (1.66–1.70) | 1.01 (0.93–1.09) | 0.91 (0.86–0.97) |
| Race/ethnicity | |||||||
| White | Ref | Ref | Ref | Ref | Ref | Ref | Ref |
| Black | 0.61 (0.58–0.64) | 1.67 (1.63–1.70) | 1.38 (1.35–1.41) | 1.16 (0.95–1.41) | 1.39 (1.36–1.42) | 1.24 (1.05–1.47) | 1.07 (0.92–1.24) |
| Hispanic | 0.41 (0.39–0.43) | 1.40 (1.35–1.44) | 1.33 (1.29–1.37) | 1.24 (0.96–1.61) | 1.33 (1.29–1.37) | 1.04 (0.83–1.30) | 0.86 (0.73–1.01) |
| Other/missing | 2.50 (2.40–2.61) | 1.06 (1.05–1.07) | 1.39 (1.37–1.40) | 1.04 (0.93–1.16) | 0.93 (0.92–0.94) | 1.10 (1.00–1.22) | 1.00 (0.93–1.07) |
| Deyo-Charlson score | |||||||
| 0 | Ref | Ref | Ref | Ref | Ref | Ref | Ref |
| 1 | 0.96 (0.93–0.99) | 1.20 (1.19–1.22) | 0.95 (0.94–0.96) | 1.02 (0.91–1.14) | 0.96 (0.95–0.97) | 0.93 (0.84–1.03) | 1.09 (1.02–1.17) |
| ≥ 2 | 0.75 (0.73–0.78) | 0.95 (0.94–0.97) | 0.58 (0.58–0.59) | 1.04 (0.94–1.16) | 0.78 (0.77–0.79) | 0.92 (0.83–1.01) | 1.46 (1.37–1.55) |
| Primary diagnosis | |||||||
| RA | Ref | Ref | Ref | Ref | Ref | Ref | Ref |
| Avascular bone necrosis | 1.03 (0.89–1.21) | 0.89 (0.84–0.95) | 0.84 (0.79–0.89) | 1.53 (0.65–3.60) | 0.82 (0.78–0.88) | 1.25 (0.77–2.02) | 0.89 (0.59–1.34) |
| Osteoarthritis | 0.93 (0.80–1.08) | 0.66 (0.62–0.70) | 0.51 (0.48–0.54) | 0.85 (0.37–1.96) | 0.66 (0.62–0.69) | 0.84 (0.53–1.32) | 0.77 (0.53–1.13) |
| Other | 0.98 (0.84–1.14) | 1.65 (1.55–1.75) | 2.30 (2.18–2.43) | 3.70 (1.59–8.59) | 1.03 (0.97–1.09) | 4.83 (3.04–7.66) | 7.22 (4.95–10.53) |
| Fracture | 0.66 (0.09–5.03) | 11.50 (3.39–39.02) | 11.84 (2.55–54.85) | Not estimable | 1.16 (0.47–2.82) | Not estimable | Not estimable |
| Insurance payer | |||||||
| Private | Ref | Ref | Ref | Ref | Ref | Ref | Ref |
| Medicare | 0.99 (0.96–1.03) | 2.06 (2.02–2.09) | 1.34 (1.32–1.36) | 1.01 (0.86–1.19) | 1.18 (1.16–1.20) | 1.04 (0.91–1.18) | 1.14 (1.04–1.26) |
| Medicaid | 1.38 (1.27–1.51) | 1.72 (1.67–1.77) | 1.70 (1.65–1.74) | 1.76 (1.43–2.17) | 1.17 (1.14–1.21) | 1.53 (1.28–1.82) | 0.89 (0.75–1.05) |
| Other | 1.92 (1.72–2.14) | 1.10 (1.06–1.14) | 1.32 (1.28–1.37) | 1.38 (1.06–1.80) | 1.00 (0.97–1.04) | 1.04 (0.82–1.32) | 0.83 (0.69–1.01) |
| Self | 1.24 (1.05–1.46) | 0.56 (0.52–0.61) | 1.50 (1.43–1.58) | 1.30 (0.84–2.03) | 1.11 (1.04–1.18) | 1.41 (1.01–1.95) | 0.90 (0.64–1.25) |
| Income category, percentile | |||||||
| 0–25th | 2.48 (2.38–2.59) | 0.81 (0.80–0.82) | 0.86 (0.85–0.87) | 0.96 (0.84–1.10) | 0.82 (0.81–0.84) | 0.98 (0.87–1.11) | 0.98 (0.90–1.06) |
| 25th–50th | 2.19 (2.12–2.27) | 0.83 (0.82–0.84) | 0.94 (0.93–0.96) | 0.99 (0.88–1.11) | 0.79 (0.78–0.80) | 1.04 (0.94–1.16) | 0.99 (0.93–1.07) |
| 50th–75th | 1.55 (1.50–1.60) | 0.86 (0.85–0.87) | 0.91 (0.90–0.92) | 0.99 (0.88–1.12) | 0.79 (0.78–0.81) | 0.99 (0.89–1.10) | 0.96 (0.89–1.03) |
| 75th–100th | Ref | Ref | Ref | Ref | Ref | Ref | Ref |
Data are OR (95% CI). Values in bold face indicate significant OR. An OR > 1 indicates that SSc patients had higher odds of that outcome, including in-hospital complication (e.g., mortality) and healthcare use (charges, stay, discharge disposition). A 95% CI that did not include unity (1.0) indicates that the association is statistically significant with a p value < 0.05.
↵* Model included the following variables: age, sex, race, Deyo-Charlson comorbidity index, the underlying primary diagnosis for THA, household income, insurance payer, SSc diagnosis.
↵** Median hospital charges were as follows: 1998, $19,717; 1999, $20,514; 2000, $22,333; 2001, $24,189; 2002, $26,729; 2003, $29,858; 2004, $32,607; 2005, $34,615; 2006, $36,164; 2007, $39,675; 2008, $43,064; 2009, $41,602; 2010, $45,186; 2011, $48,898; 2012, $48,927; 2013, $50,827; 2014, $51,482. SSc: systemic sclerosis; RA: rheumatoid arthritis; THA: total hip arthroplasty.