Modified frailty index as a predictor of the long-term functional result in patients undergoing primary total hip arthroplasty

Abstract

Objectives: Total hip arthroplasty (THA) is a well-approved method for the treatment of end-stage osteoarthritis (OA). Due to rising life expectancy, elderly patients burdened with multimorbidity are subjected to THA. Some of these patients present significant depletion of physiological reserves, which is described as the frailty syndrome. This study aims to assess the influence of frailty on the THA outcomes in OA patients. Material and methods: A single-center observational study was conducted to investigate the effect of frailty measured by the modified frailty index-5 (mFI-5) and modified frailty index-11 (mFI-11) on the long-term post-THA outcomes. The analysis included 597 initially screened patients subjected to unilateral, primary THA due to hip OA. The outcomes were assessed during a follow-up visit 3 years after THA. The primary outcome measures were patient-reported (the Western Ontario and McMaster Universities Osteoarthritis Index-WOMAC) and physician-reported scales (the Harris Hip Score-HHS). The secondary outcome measures were the length of hospital stay (LOS), pain complaints, complications, and satisfaction. A correlation analysis was performed (Spearman's R). Results: Three hundred sixty-five patients met the eligibility criteria, including 57.26% women (n = 209) and 42.74% men (n = 156). The mean age was 65.11 ±12.12 years. Patients with high values of mFI-5 (r = 0.19; p < 0.05) and mFI-11 (r = 0.22; p < 0.01) achieved less satisfactory functional outcomes after THA (WOMAC). After age adjustment, mFI-11 (r = 0.17; p < 0.05) was a better predictor of functional outcome (WOMAC) than mFI-5 was (r = 0.15; p = 0.07). The mFI-5 (r = 0.25; p < 0.001) and mFI-11 (r = 0.29; p < 0.001) correlated with longer LOS. Conclusions: The modified frailty index-5 (mFI-5) and modified frailty index-11 (mFI-11) are useful tools to identify patients subjected to THA at a high risk of poor functioning after the procedure. They can be used in preoperative counseling before obtaining informed consent to support surgical decision-making. To our knowledge, this is the first study investigating the impact of the mFI on long-term postoperative functional results in OA treated with THA.

The Update on Instruments Used for Evaluation of Comorbidities in Total Hip Arthroplasty

“…Therefore, it is the most frequently used comorbidity index in THA research [ 13 ] Modified Frailty Index (mFI) According to research, mFI appears to be a reliable index of predicting THA outcomes, including 30-day complications rate, reoperation risk, and length of stay and mortality [ 17 ]. The mFI-11 and mFI-5 can predict the long-term functional outcome of THA and hospitalization duration regardless of age [ 18 ] Elixhauser Comorbidity Method (ECM) Ondneck et al study shows ECM's superiority over mFI and the CCI in predicting THA's adverse outcomes. The ECM outperformed demographic indicators, including age, which is the best demographic index of the procedure's outcome proven in medical practice in most groups presented in the study [ 23 ].…”

“…Previous studies have shown that mFI is a stronger predictor than age or ASA in predicting the length of hospitalization, complications, reoperation, and mortality after THA [ 17 ]. The mFI was recently proven to predict long-term functional outcomes (WOMAC) and length of hospital stay in patients after THA [ 18 ].…”

“… Predictors of the use of analgesic drugs 1 year after joint replacement: a single-centre analysis of 13,000 hip and knee replacements [ 60 ] Rajamaki, TJ 2020 Retrospective 6238 CCI Use of opioids and other analgesics 1 year after surgery Higher CCI is a risk factor of increase postoperative use of analgesics CCI of two or more was associated with a higher risk ratio for the use of any analgesic drugs 4. Modified frailty index as a predictor of the long-term functional result in patients undergoing primary total hip arthroplasty [ 18 ] Pulik, Ł 2020 Retrospective 365 mFI-5 mFI-11 WOMAC (The Western Ontario and McMaster Universities Osteoarthritis Index) HHS (Harris Hip Score) VAS (Visual Analogue Scale) HKASS LOS (length of stay) Complication The mFI-5 and mFI-11 are predictors of WOMAC and LOS 5. Risk stratification in primary total joint arthroplasty: the current state of knowledge [ 11 ] Gronbeck, C 2019 Retrospective 5251 ASA CCI Complication Readmission Reoperation Mortality ASA was a risk factor for most assessed outcomes* ASA was a more reliable risk stratification than CCI* 6.…”

A Simplified Frailty Index Predicts Mortality in Older Adults in Beijing

“…This supports the findings of Mitnitski’s study. 7 Łukasz Pulik 15 and his team also made a modified frailty index (m-FI5 and m-FI11) as a predictor of the long-term functional result in patients undergoing primary total hip arthroplasty. We modified the 68-item FI to 27 items, which included information regarding physical and psychological characteristics, disease status, as well as other variables that showed a correlation between frailty and age.…”

“…However, comparisons with previous studies are difficult as different variables are frequently used to define frailty. 5 , 15 , 16 …”