Health Related Quality of Life in Adults with 13 Chronic Diseases before Age 65 and after Age 65 Using Fuzzy Rough Analysis of SF-36 Domains

An important factor in quality-of-life research is age. The deterioration of health-related quality of life (HR - QoL) in a group of patients is repeatedly emphasized. It is necessary to analyze which diseases (groups of diseases), in which spheres and how strongly they reduce HR - QoL. The purpose of this study was to analyze the level of HR-QoL experienced in each sphere and evaluate their influence in a given disease before and at age 65 and older. The cross-sectional study was carried out in Poland on a group of 7620 patients in 13 different disease groups. HR-QoL was assessed using the SF-36. Inclusion criteria were: age≥18 years, chronic disease ≥2 years, no other comorbidities (double verification of the criterion: treatment at a specialist clinic for a given chronic disease and questions excluding other comorbidities), and consent to participate in the study. Analysis was performed in two age groups (&;lt65 and ≥ 65 years old) using fuzzy set method, a hierarchical cluster analysis and Student's t test. Correlation analysis in the group of patients before 65 years of age indicated a strong correlation between the variables: LD-RE (0.88), DSD-C-RP (0.75). In the group aged 65 and older indicated strong correlations between: NS-HCh (0.78) and NS-BP (0.70). CD, CVD and NS (with the exception of the RE sphere) were among the group of diseases that most severely lowered HR - QoL in the individual spheres of the SF-36 in the group of patients under 65 years of age. Among patients 65 and older, the group of diseases lowering HR - QoL was much more numerous: CD, CVD, NS, DM, DS, DSD-C, DSD-Th and depended on the individual spheres of quality of life assessed in the SF-36. DSD-C, DM, DS lowered HR - QoL of the older group of patients in the spheres: PF, RP, BP, GH, VT, SF, RE.