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Impact of body mass on hospital resource use in total hip arthroplasty
John A Batsis1, James M Naessens, Mark T Keegan
1Section of General Internal Medicine, Department of Medicine, Dartmouth-Hitchcock Medical Center, 1 Medical Center Drive, Lebanon, NH 03756, USA. john.batsis@gmail.com
Insights
Body mass index (BMI) did not affect length of stay or overall costs for elective total hip arthroplasty (THA). Morbidly obese patients had higher operative costs but similar resource utilization, indicating obesity does not increase THA costs.
Area of Science:
- Orthopedics
- Public Health
- Health Economics
Background:
- Obesity is a growing public health concern, impacting various medical procedures.
- Understanding the relationship between body mass index (BMI) and outcomes in total hip arthroplasty (THA) is crucial for resource allocation and patient management.
Purpose of the Study:
- To investigate the association between pre-operative BMI and post-operative outcomes.
- To evaluate the impact of BMI on resource utilization, including length of stay (LOS) and costs, following elective THA.
Main Methods:
- Retrospective cohort analysis of 5642 primary elective THA patients (1996-2004).
- Patients stratified into normal, overweight, obese, and morbidly obese BMI categories.
- Regression analyses used to assess outcomes, including LOS and total costs.
Main Results:
- No significant differences in adjusted length of stay or overall institutional costs across BMI groups.
- Morbidly obese patients incurred higher operative and anesthesia costs but lower blood bank costs.
- Higher likelihood of nursing home transfer for morbidly obese patients, but no differences in 30-day mortality, re-admissions, or re-operations.
Conclusions:
- Pre-operative BMI does not significantly impact length of stay or overall acute care costs for elective THA.
- Despite increased operative expenses, obesity does not lead to greater resource utilization in elective THA.
- These findings suggest that elective THA is resource-efficient across different BMI categories.
Objective:
To determine the impact of BMI on post-operative outcomes and resource utilization following elective total hip arthroplasty (THA).
Design:
A retrospective cohort analysis on all primary elective THA patients between 1996 and 2004. Primary outcomes investigated using regression analyses included length of stay (LOS) and costs (US dollars).
Setting:
Mayo Clinic Rochester, a tertiary care centre.
Subjects:
Patients were stratified by pre-operative BMI as normal (18.5-24.9 kg/m(2)), overweight (25.0-29.9 kg/m(2)), obese (30.0-34.9 kg/m(2)) and morbidly obese (> or =35.0 kg/m(2)). Of 5642 patients, 1362 (24.1 %) patients had a normal BMI, 2146 (38.0 %) were overweight, 1342 (23.8 %) were obese and 792 (14.0 %) were morbidly obese.
Results:
Adjusted LOS was similar among normal (4.99 d), overweight (5.00 d), obese (5.02 d) and morbidly obese (5.17 d) patients (P = 0.20). Adjusted overall episode costs were no different (P = 0.23) between the groups of normal ($17,211), overweight ($17,462), obese ($17,195) and morbidly obese ($17,655) patients. Overall operative and anaesthesia costs were higher in the morbidly obese group ($5688) than in normal ($5553), overweight ($5549) and obese ($5593) patients (P = 0.03). Operating room costs were higher in morbidly obese patients ($3418) than in normal ($3276), overweight ($3291) and obese ($3340) patients (P < 0.001). Post-operative costs were no different (P = 0.30). Blood bank costs differed (P = 0.002) and were lower in the morbidly obese group ($180) compared with the other patient groups (P < 0.05). Other differences in costs were not significant. Morbidly obese patients were more likely to be transferred to a nursing home (24.1 %) than normal (18.4 %), overweight (17.9 %) or obese (16.0 %) patients (P = 0.001 each). There were no differences in the composite endpoint of 30 d mortality, re-admissions, re-operations or intensive care unit utilization.
Conclusions:
BMI in patients undergoing primary elective THA did not impact LOS or overall institutional acute care costs, despite higher operative costs in morbidly obese patients. Obesity does not increase resource utilization for elective THA.
