Ten-year risk of complication and mortality after total hip arthroplasty in morbidly obese patients: a population study

Ten-year risk of complication and mortality after total hip arthroplasty in morbidly obese patients: a population study

Can J Surg 2019;62(6):442-449 | PDF | Appendix

Mina Tohidi, MD; Susan B. Brogly, PhD; Katherine Lajkosz, MSc; Mark M. Harrison, MD; Aaron R. Campbell, MD; Elizabeth VanDenKerkhof, PhD; Stephen M. Mann, MD


Background: The relationship between morbid obesity and long-term patient outcomes after primary total hip arthroplasty (THA) has been understudied. The purpose of this study was to determine the association between morbid obesity and 10-year complications (revision surgery, reoperation, dislocation) and mortality in patients undergoing primary THA.

Methods: We conducted a population-based cohort study of patients aged 45–74 years who underwent primary THA for osteoarthritis between 2002 and 2007 using Ontario administrative health care databases. Patients were followed for 10 years. We estimated risk ratios (RRs) of mortality, reoperation, revision and dislocation in patients with body mass index (BMI) greater than 45 kg/m2 (morbidly obese patients) compared with patients with a BMI of 45 kg/m2 or less (nonmorbidly obese patients).

Results: There were 22 251 patients in the study cohort, of whom 726 (3.3%) were morbidly obese. Morbid obesity was associated with higher 10-year risk of death (RR 1.38, 95% confidence interval [CI] 1.18–1.62). Risks of revision (RR 1.43, 95% CI 0.96–2.13) and dislocation (RR 2.38, 95% CI 1.38–4.10) were higher in morbidly obese men than in nonmorbidly obese men; there were no associations between obesity and revision or dislocation in women. Risk of reoperation was higher in morbidly obese women than in nonmorbidly obese women (RR 1.59, 95% CI 1.05–2.40); there was no association between obesity and reoperation in men.

Conclusion: Morbidly obese patients undergoing primary THA are at higher risk of long-term mortality and complications. There were differences in complication risk by sex. The results of this study should inform perioperative counselling of patients considering THA.


Contexte : Le lien entre l’obésité morbide et les issues à long terme des patients ayant subi une arthroplastie totale primaire de la hanche (ATH) est sous-étudié. Cette étude visait à caractériser l’association entre l’obésité morbide et les complications (chirurgie de révision, réintervention, dislocation) et la mortalité sur 10 ans chez les patients ayant subi une ATH.

Méthodes : Nous avons mené une étude de cohorte basée sur la population auprès de patients de 45 à 74 ans atteints d’arthrose ayant subi une ATH primaire entre 2002 et 2007 en utilisant les bases de données administratives en santé de l’Ontario. Les patients ont été suivis pour une période de 10 ans. Nous avons estimé des rapports de risque (RR) pour la mortalité, la réintervention, la chirurgie de révision et la dislocation chez les patients ayant un indice de masse corporelle (IMC) de plus de 45 kg/m2 (obésité morbide) en comparaison avec les patients ayant un IMC de 45 kg/m2 ou moins.

Résultats : L’étude de cohorte comptait 22 251 patients, dont 726 (3,3 %) étaient atteints d’obésité morbide. L’obésité morbide a été associée à un risque de mortalité sur 10 ans accru (RR 1,38; intervalle de confiance [IC] de 95 % 1,18–1,62). Le risque de chirurgie de révision (RR 1,43; IC de 95 % 0,96–2,13) et de dislocation (RR 2,38; IC de 95 % 1,38–4,10) était plus élevé chez les hommes atteints d’obésité morbide que chez les autres hommes; aucune association n’a été observée entre l’obésité et la chirurgie de révision ou la dislocation chez les femmes. Par contre, le risque de réintervention était accru chez les femmes atteintes d’obésité morbide (RR 1,59; IC de 95 % 1,05–2,40), mais aucune association n’a été établie entre l’obésité et la réintervention chez les hommes.

Conclusion : Les patients atteints d’obésité morbide qui subissent une ATH primaire courent un risque plus élevé de complications et de mortalité à long terme. Des différences ont été observées dans les risques de complications selon le sexe. Les résultats de cette étude devraient guider l’offre de conseils aux patients qui envisagent l’ATH.

Accepted Apr. 2, 2019

Acknowledgements: This study was supported by ICES, which is funded by an annual grant from the Ontario Ministry of Health and Long-Term Care (MOHLTC). The opinions, results and conclusions reported in this paper are those of the authors and are independent from the funding sources. No endorsement by ICES or the Ontario MOHLTC is intended or should be inferred. Parts of this material are based on data and information compiled and provided by CIHI. However, the analyses, conclusions, opinions and statements expressed herein are those of the authors and not necessarily those of CIHI. Funding for this project was provided by the Department of Surgery, Queen’s University.

Affiliations: From the Division of Orthopaedic Surgery, Department of Surgery, Kingston Health Sciences Centre, Queen’s University, Kingston, Ont. (Tohidi, Harrison, Campbell, Mann); the Department of Public Health Sciences, Queen’s University, Kingston, Ont. (Tohidi); the Department of Surgery, Queen’s University, Kingston, Ont. (Brogly); ICES, Queen’s University, Kingston, Ont. (Brogly, Lajkosz, VanDenKerkhof); the School of Nursing, Queen’s University, Kingston, Ont. (VanDenKerkhof); and the Department of Anesthesiology and Perioperative Medicine, Kingston Health Sciences Centre, Kingston, Ont. (VanDenKerkhof).

Competing interests: None declared.

Contributors: M. Tohidi, S. Brogly, M. Harrison, A. Campbell and S. Mann designed the study. K. Lajkosz acquired and analyzed the data, which M. Tohidi, S. Brogly, E. VanDerKerkhof and S. Mann also analyzed. M. Tohidi wrote the article, which all authors reviewed and approved for publication. All authors agreed to be accountable for all aspects of the work.

DOI: 10.1503/cjs.017318

Correspondence to: S.M. Mann, Department of Surgery, Queen’s University, Victory 3, Kingston Health Sciences Centre, 76 Stuart St, Kingston ON K7L 2V7, steve.mann@kingstonhsc.ca