In the JournalsPerspective

Poverty fails to explain racial disparities in total knee replacement

Anne R. Bass

Poverty does not increase the risk for total knee replacement failure or revision among black or white patients, and fails to explain observed racial disparities associated with the procedure, according to data published in Arthritis Care & Research.

“Blacks are at increased risk of total knee replacement (TKR) revision than whites, and blacks report significantly more pain and worse function 2 years after TKR,” Anne R. Bass, MD, of the Hospital for Special Surgery, and colleagues wrote. “We previously showed that racial disparities in patient reported outcomes are strongly influenced by community poverty and education. Whether disparities in TKR revision risk are related to poverty is unknown.”

To determine whether community poverty can explain racial disparities in patients who undergo total knee replacement, Bass and colleagues studied all black and white residents of New York state enrolled in the Hospital for Special Surgery knee replacement registry, and who received the procedure between Jan. 1, 2008, and Feb. 6, 2012.

 
Poverty does not increase the risk for total knee replacement failure among black or white patients, according to data.
Source: Adobe

The researchers included 4,062 patients who provided baseline questionnaire information, had a geo-codable address, were state residents, were either black or white and underwent unilateral total knee replacement in their study. Among the participants, 9% were black and 8% lived in census tracts where more than 20% lived below the poverty line.

These participants were linked to the Statewide Planning and Research Cooperative System database, with information spanning from Jan. 1, 2008, to Dec. 31, 2014, to find revisions performed at other medical centers. In addition, the researchers linked participants to residential census tracts using geo-coded addresses.

Bass and colleagues used multivariate Cox regression to determine predictors of total knee replacement revision, with multivariate logistic regression used to analyze predictors of failure. Failure was defined as undergoing revision in New York state within 2 years following surgery, or demonstrating a “not improved” or “worsening” quality of life score 2 years after surgery.

According to the researchers, 3% of participants required revision a median of 454 days following surgery. The risk for revision was higher among black participants compared with whites (HR = 1.69; 95% CI, 1.01-2.81). However, after completing multivariable analysis, only younger age, male sex and constrained prosthesis were predictors of surgery revision. Failure occurred in 7% of patients who completed 2-year follow-up surveys. Risk factors for failure were nonosteoarthritis indications for total knee replacement, low surgeon volume and low expectations survey score.

Neither black race nor community poverty were predictors for failure. In addition, poverty was not associated with surgery revision.

“To our surprise, community poverty had no relationship to revision rates and, after controlling for other variables, race was not a factor either,” Bass told Healio Rheumatology. “Our explanation is that everyone in our study had surgery at HSS, a high-volume orthopedic hospital, since high hospital and surgeon volume is known to be associated with better TKR outcomes.” – by Jason Laday

Disclosure: The researchers report no relevant financial disclosures.

Anne R. Bass

Poverty does not increase the risk for total knee replacement failure or revision among black or white patients, and fails to explain observed racial disparities associated with the procedure, according to data published in Arthritis Care & Research.

“Blacks are at increased risk of total knee replacement (TKR) revision than whites, and blacks report significantly more pain and worse function 2 years after TKR,” Anne R. Bass, MD, of the Hospital for Special Surgery, and colleagues wrote. “We previously showed that racial disparities in patient reported outcomes are strongly influenced by community poverty and education. Whether disparities in TKR revision risk are related to poverty is unknown.”

To determine whether community poverty can explain racial disparities in patients who undergo total knee replacement, Bass and colleagues studied all black and white residents of New York state enrolled in the Hospital for Special Surgery knee replacement registry, and who received the procedure between Jan. 1, 2008, and Feb. 6, 2012.

 
Poverty does not increase the risk for total knee replacement failure among black or white patients, according to data.
Source: Adobe

The researchers included 4,062 patients who provided baseline questionnaire information, had a geo-codable address, were state residents, were either black or white and underwent unilateral total knee replacement in their study. Among the participants, 9% were black and 8% lived in census tracts where more than 20% lived below the poverty line.

These participants were linked to the Statewide Planning and Research Cooperative System database, with information spanning from Jan. 1, 2008, to Dec. 31, 2014, to find revisions performed at other medical centers. In addition, the researchers linked participants to residential census tracts using geo-coded addresses.

Bass and colleagues used multivariate Cox regression to determine predictors of total knee replacement revision, with multivariate logistic regression used to analyze predictors of failure. Failure was defined as undergoing revision in New York state within 2 years following surgery, or demonstrating a “not improved” or “worsening” quality of life score 2 years after surgery.

According to the researchers, 3% of participants required revision a median of 454 days following surgery. The risk for revision was higher among black participants compared with whites (HR = 1.69; 95% CI, 1.01-2.81). However, after completing multivariable analysis, only younger age, male sex and constrained prosthesis were predictors of surgery revision. Failure occurred in 7% of patients who completed 2-year follow-up surveys. Risk factors for failure were nonosteoarthritis indications for total knee replacement, low surgeon volume and low expectations survey score.

Neither black race nor community poverty were predictors for failure. In addition, poverty was not associated with surgery revision.

“To our surprise, community poverty had no relationship to revision rates and, after controlling for other variables, race was not a factor either,” Bass told Healio Rheumatology. “Our explanation is that everyone in our study had surgery at HSS, a high-volume orthopedic hospital, since high hospital and surgeon volume is known to be associated with better TKR outcomes.” – by Jason Laday

Disclosure: The researchers report no relevant financial disclosures.

    Perspective
    Carlos M. Alonso

    Carlos M. Alonso

    Psoriatic arthritis is a common inflammatory arthritis that classically occurs in persons with psoriasis. It has been recognized that a large proportion of patients with PsA may develop an aggressive, destructive arthritis; however, it remains unclear if the impact of biologic DMARDs has led to a decreased need for joint surgery in PsA as has been demonstrated in rheumatoid arthritis.

    This Danish nationwide registry-based study by Guldberg-Moller and colleagues showed that the cumulative incidence of any joint surgery among patients with PsA was 1.7%, 10.4%, 28.9% after 5, 10, and 15 years respectively — which was double that of individuals in the general population cohort at any given calendar period. Of further interest, patients with PsA in the 18-40 year old cohort had a higher incidence rate of joint surgery than those in the general population aged 60 years and older at 15 years.

    This study illustrates a significant health burden associated with PsA and underscores the need to implement aggressive treat-to-target strategies in order to prevent erosive disease and loss of joint function, which may lead to either joint sacrificing or non-joint sacrificing surgeries. Additionally, this study serves as a basis for future studies to assess the impact of biologic DMARD therapy on reducing the incidence rates of joint surgeries in the psoriatic arthritis population.

    • Carlos M. Alonso, MD, FACR, RhMSUS
    • Advanced Rheumatology of South Florida
      Member, Medical Policy Committee
      United Rheumatology

    Disclosures: Alonso reports no relevant financial disclosures.