Evaluation of the quality of life dynamics in comorbid patients with hip and knee joint arthroplasty

BACKGROUND: In recent years, in traumatology and orthopedics, statistical methods of survival analysis have been used to assess long-term treatment results, which make it possible to take into account censored clinical observations. This method of statistical analysis allows to take into account both cases of attrition from care and cases of incomplete follow-ups. There is no concurrent point of view on the dependence of the long-term results of hip and knee arthroplasty on the comorbidity of a patient. This circumstance fosters a special study using survival analysis.

AIM: To study the long-term results of total hip and knee arthroplasty in the patients with osteoarthritis. To determine the patients’ quality of life depending on the presence of pronounced concomitant pathology.

MATERIALS AND METHODS: The groups of patients with comorbidity and without significant concomitant pathology have been compared. The first group included 806 patients aged 19 to 88 years who underwent primary total hip replacement in the Clinic of Traumatology and Orthopedics of the North-Western State Medical University named after I.I. Mechnikov from 2014 to 2018 in connection with osteoarthritis. The second group consisted of 376 patients aged 43 to 85 years who underwent primary total KR due to osteoarthritis in the V.A. Baranov Republican Hospital (Petrozavodsk) in 2016–2019. Statistical data processing and graph design have been carried out with R programming language with open access via https://cran.r-project.org. The probability of maintaining a satisfactory assessment of the quality of life by a certain observation point t (year of observation) has been assessed using the Kaplan–Mayer method. The logrank test has been used in order to compare the probability of maintaining a satisfactory assessment of quality of life during the entire follow-up period in the groups of patients with and without polymorbidity.

RESULTS: At the end of the 5th year of follow-up, the probability of maintaining excellent and good quality of life after hip replacement with a 95% confidence interval was 0.88 (0.81; 0.94) in the patients without comorbidity, 0.84 (0.79; 0.88) in the patients with severe concomitant pathology. Test statistics (Z = 0.93) and p = 0.31 indicate statistically insignificant differences in survival curves between the groups of patients with varying degrees of comorbidity.

When analyzing the five-year results of the knee replacement, the quality of life among patients with high and low comorbidity did not differ significantly. The probability of excellent and good quality of life at the 5th year of follow-up in practically healthy patients and in cases of mild therapeutic disease was 0.78 (0.67; 0.88); with a high degree of comorbidity — 0.74 (0.65; 0.81).

CONCLUSIONS: By the end of the 5th year of follow-up of the patients who have undergone hip or knee replacement due to osteoarthritis, an excellent and good quality of life can be expected on average in 80% of the patients. Satisfactory and unsatisfactory — in 20% of the patients. Excellent and good quality of life 5 years after hip or knee arthroplasty in the patients with severe comorbidity does not significantly differ from that in the practically healthy patients without comorbidity (p > 0,05).