Evaluation of the quality of life dynamics by methods of survival analysis in patients with hip joint ar-throplasty

Abstract. Introduction The study deals with the approaches to the analysis of the dynamics in the course of a long-term postoperative period in patients who underwent hip arthroplasty. Aim To feature the variants in the course of a long-term postoperative period in patients who underwent arthroplasty of the hip joint. Materials and methods 806 patients (age range, 9 to 88 years) suffering from osteoarthritis underwent primary total hip arthroplasty (THA). Statistical analysis was carried out using the R programming language, freely available at https://cran.r-project.org. The probability of maintaining satisfactory quality of life (QoL) at a certain time of observation t (year of observation) was assessed with the Kaplan-Meier method. To compare the likelihood of maintaining a satisfactory QoL level throughout the observation period in several groups (for example, patients of different sexes), the logrank test was used. Results By year 6 of follow-up, the following tendency emerges regarding the age of the patients. The indicators are the best in young patients (up to 44 years old), where the probability of maintaining a satisfactory QoL evaluation was 0.92 (0.84; 0.96). A somewhat lower values were observed in the patients of the middle age group (from 45 to 64 years old) – 0.87 (0.78; 0.92). Excellent and good QoL was found in patients aged 65 and older, 0.83 (0.76; 0.88). Discussion Survival analysis methods have been used for the first time in traumatology and orthopedics. Previous researchers assessed the long-term results of the quality of specialized traumatological and orthopedic care without considering censored observations. Thus, the coverage of the investigated clinical observations averaged 80-85%. Information about 10-15% of cases was excluded from the studies. The proposed method of analysis provides information about all patients. Conclusions Five years following THA, an excellent and good quality of life could be expected in 85 % of patients. Satisfactory and poor levels are observed in 15 % of patients. At 5-year follow-up after THA, the quality of life is worse in older female groups with severe concomitant pathology; however, there are no statistically significant differences. This is a tendency, and requires further study.