Effect of Body Mass Index and Psychosocial Traits on Total Knee Replacement Costs in Patients with Osteoarthritis.
Clinical and psychosocial attributes are associated with clinical outcomes after total knee replacement (TKR) surgery in patients with osteoarthritis (OA), but their relationship with TKR-related costs is less clear. Our objective was to evaluate the effect of clinical and psychosocial attributes on TKR costs.



We conducted a 6-month prospective cohort study of patients with knee OA who underwent TKR. We examined baseline demographic, clinical [body mass index (BMI) and comorbidities], and psychosocial attributes (social support, locus of control, coping, depression, anxiety, stress, and self-efficacy); baseline and 6-month OA clinical outcomes [Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain and function]; and 6-month direct and indirect TKR-related costs. Multiple regression was performed to identify determinants of TKR-related costs.



We included 212 patients; 66% were women, 71% were white, and the mean age was 65.2 years. The mean baseline WOMAC pain score was 55 (SD 19) and WOMAC function score was 54 (SD 20). Mean total TKR-related costs were US$30,831 (SD $9893). Multivariate regression analyses showed that increasing BMI and anxiety levels and decreasing levels of positive social interactions were associated with increased costs. A lower cost scenario with a lower range of normal BMI (19.5), highest positive social interaction, and no anxiety predicted TKR costs to be $22,247. Predicted costs in obese patients (BMI 36) with lowest positive social interaction and highest anxiety were $58,447.



Increased baseline BMI, anxiety, and poor social support lead to higher TKR-related costs in patients with knee OA. Preoperative interventions targeting these factors may reduce TKR-related costs, and therefore be cost-effective.
From the Hospital Municipal Dr. Héctor M. Cura, Buenos Aires, Argentina; University of Texas MD Anderson Cancer Center; St. Luke's Episcopal Health System, Houston, Texas, USA.C.A. Waimann, MD, Hospital Municipal Dr. Héctor M Cura; R.J. Fernandez-Mazarambroz, BBA, University of Texas MD Anderson Cancer Center; S.B. Cantor, PhD, University of Texas MD Anderson Cancer Center; M.A. Lopez-Olivo, MD, PhD, University of Texas MD Anderson Cancer Center; A.G. Barbo, MS, University of Texas MD Anderson Cancer Center; G.C. Landon, MD, St. Luke's Episcopal Health System; S.J. Siff, MD, St. Luke's Episcopal Health System; H. Lin, PhD, University of Texas MD Anderson Cancer Center; M.E. Suarez-Almazor, MD, PhD, University of Texas MD Anderson Cancer Center.
Christian A
CA
Waimann
From the Hospital Municipal Dr. Héctor M. Cura, Buenos Aires, Argentina; University of Texas MD Anderson Cancer Center; St. Luke's Episcopal Health System, Houston, Texas, USA.C.A. Waimann, MD, Hospital Municipal Dr. Héctor M Cura; R.J. Fernandez-Mazarambroz, BBA, University of Texas MD Anderson Cancer Center; S.B. Cantor, PhD, University of Texas MD Anderson Cancer Center; M.A. Lopez-Olivo, MD, PhD, University of Texas MD Anderson Cancer Center; A.G. Barbo, MS, University of Texas MD Anderson Cancer Center; G.C. Landon, MD, St. Luke's Episcopal Health System; S.J. Siff, MD, St. Luke's Episcopal Health System; H. Lin, PhD, University of Texas MD Anderson Cancer Center; M.E. Suarez-Almazor, MD, PhD, University of Texas MD Anderson Cancer Center.
Rodrigo J
RJ
Fernandez-Mazarambroz
From the Hospital Municipal Dr. Héctor M. Cura, Buenos Aires, Argentina; University of Texas MD Anderson Cancer Center; St. Luke's Episcopal Health System, Houston, Texas, USA.C.A. Waimann, MD, Hospital Municipal Dr. Héctor M Cura; R.J. Fernandez-Mazarambroz, BBA, University of Texas MD Anderson Cancer Center; S.B. Cantor, PhD, University of Texas MD Anderson Cancer Center; M.A. Lopez-Olivo, MD, PhD, University of Texas MD Anderson Cancer Center; A.G. Barbo, MS, University of Texas MD Anderson Cancer Center; G.C. Landon, MD, St. Luke's Episcopal Health System; S.J. Siff, MD, St. Luke's Episcopal Health System; H. Lin, PhD, University of Texas MD Anderson Cancer Center; M.E. Suarez-Almazor, MD, PhD, University of Texas MD Anderson Cancer Center.
Scott B
SB
Cantor
From the Hospital Municipal Dr. Héctor M. Cura, Buenos Aires, Argentina; University of Texas MD Anderson Cancer Center; St. Luke's Episcopal Health System, Houston, Texas, USA.C.A. Waimann, MD, Hospital Municipal Dr. Héctor M Cura; R.J. Fernandez-Mazarambroz, BBA, University of Texas MD Anderson Cancer Center; S.B. Cantor, PhD, University of Texas MD Anderson Cancer Center; M.A. Lopez-Olivo, MD, PhD, University of Texas MD Anderson Cancer Center; A.G. Barbo, MS, University of Texas MD Anderson Cancer Center; G.C. Landon, MD, St. Luke's Episcopal Health System; S.J. Siff, MD, St. Luke's Episcopal Health System; H. Lin, PhD, University of Texas MD Anderson Cancer Center; M.E. Suarez-Almazor, MD, PhD, University of Texas MD Anderson Cancer Center.
Maria A
MA
Lopez-Olivo
From the Hospital Municipal Dr. Héctor M. Cura, Buenos Aires, Argentina; University of Texas MD Anderson Cancer Center; St. Luke's Episcopal Health System, Houston, Texas, USA.C.A. Waimann, MD, Hospital Municipal Dr. Héctor M Cura; R.J. Fernandez-Mazarambroz, BBA, University of Texas MD Anderson Cancer Center; S.B. Cantor, PhD, University of Texas MD Anderson Cancer Center; M.A. Lopez-Olivo, MD, PhD, University of Texas MD Anderson Cancer Center; A.G. Barbo, MS, University of Texas MD Anderson Cancer Center; G.C. Landon, MD, St. Luke's Episcopal Health System; S.J. Siff, MD, St. Luke's Episcopal Health System; H. Lin, PhD, University of Texas MD Anderson Cancer Center; M.E. Suarez-Almazor, MD, PhD, University of Texas MD Anderson Cancer Center.
Andrea G
AG
Barbo
From the Hospital Municipal Dr. Héctor M. Cura, Buenos Aires, Argentina; University of Texas MD Anderson Cancer Center; St. Luke's Episcopal Health System, Houston, Texas, USA.C.A. Waimann, MD, Hospital Municipal Dr. Héctor M Cura; R.J. Fernandez-Mazarambroz, BBA, University of Texas MD Anderson Cancer Center; S.B. Cantor, PhD, University of Texas MD Anderson Cancer Center; M.A. Lopez-Olivo, MD, PhD, University of Texas MD Anderson Cancer Center; A.G. Barbo, MS, University of Texas MD Anderson Cancer Center; G.C. Landon, MD, St. Luke's Episcopal Health System; S.J. Siff, MD, St. Luke's Episcopal Health System; H. Lin, PhD, University of Texas MD Anderson Cancer Center; M.E. Suarez-Almazor, MD, PhD, University of Texas MD Anderson Cancer Center.
Glenn C
GC
Landon
From the Hospital Municipal Dr. Héctor M. Cura, Buenos Aires, Argentina; University of Texas MD Anderson Cancer Center; St. Luke's Episcopal Health System, Houston, Texas, USA.C.A. Waimann, MD, Hospital Municipal Dr. Héctor M Cura; R.J. Fernandez-Mazarambroz, BBA, University of Texas MD Anderson Cancer Center; S.B. Cantor, PhD, University of Texas MD Anderson Cancer Center; M.A. Lopez-Olivo, MD, PhD, University of Texas MD Anderson Cancer Center; A.G. Barbo, MS, University of Texas MD Anderson Cancer Center; G.C. Landon, MD, St. Luke's Episcopal Health System; S.J. Siff, MD, St. Luke's Episcopal Health System; H. Lin, PhD, University of Texas MD Anderson Cancer Center; M.E. Suarez-Almazor, MD, PhD, University of Texas MD Anderson Cancer Center.
Sherwin J
SJ
Siff
From the Hospital Municipal Dr. Héctor M. Cura, Buenos Aires, Argentina; University of Texas MD Anderson Cancer Center; St. Luke's Episcopal Health System, Houston, Texas, USA.C.A. Waimann, MD, Hospital Municipal Dr. Héctor M Cura; R.J. Fernandez-Mazarambroz, BBA, University of Texas MD Anderson Cancer Center; S.B. Cantor, PhD, University of Texas MD Anderson Cancer Center; M.A. Lopez-Olivo, MD, PhD, University of Texas MD Anderson Cancer Center; A.G. Barbo, MS, University of Texas MD Anderson Cancer Center; G.C. Landon, MD, St. Luke's Episcopal Health System; S.J. Siff, MD, St. Luke's Episcopal Health System; H. Lin, PhD, University of Texas MD Anderson Cancer Center; M.E. Suarez-Almazor, MD, PhD, University of Texas MD Anderson Cancer Center.
Heather
H
Lin
From the Hospital Municipal Dr. Héctor M. Cura, Buenos Aires, Argentina; University of Texas MD Anderson Cancer Center; St. Luke's Episcopal Health System, Houston, Texas, USA.C.A. Waimann, MD, Hospital Municipal Dr. Héctor M Cura; R.J. Fernandez-Mazarambroz, BBA, University of Texas MD Anderson Cancer Center; S.B. Cantor, PhD, University of Texas MD Anderson Cancer Center; M.A. Lopez-Olivo, MD, PhD, University of Texas MD Anderson Cancer Center; A.G. Barbo, MS, University of Texas MD Anderson Cancer Center; G.C. Landon, MD, St. Luke's Episcopal Health System; S.J. Siff, MD, St. Luke's Episcopal Health System; H. Lin, PhD, University of Texas MD Anderson Cancer Center; M.E. Suarez-Almazor, MD, PhD, University of Texas MD Anderson Cancer Center. msalmazor@mdanderson.org.
Maria E
ME
Suarez-Almazor
D000223:Adaptation, Psychological; D000368:Aged; D001007:Anxiety / Q000523:psychology; D019645:Arthroplasty, Replacement, Knee / Q000191:economics / Q000523:psychology*; D015992:Body Mass Index; D003863:Depression / Q000523:psychology; D005260:Female; D006801:Humans; D007389:Internal-External Control; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000191:economics / Q000523:psychology / Q000601:surgery*; D011446:Prospective Studies; D020377:Self Efficacy; D012944:Social Support; D013315:Stress, Psychological / Q000523:psychology
ECONOMIC EVALUATION; OBESITY; OSTEOARTHRITIS; PSYCHOSOCIAL DETERMINANTS; TOTAL KNEE REPLACEMENT