Qualidade de vida entre pacientes com doença renal crônica em hemodiálise: seguimento de dois anos

Abstract

Kidney transplantation is the therapy that offers longest lifetime and best quality of life (QL) in patients with chronic kidney disease (CKD). However, worldwide there is lack of organs to transplant, causing the need for long-term dialysis therapy. Objectives: To identify changes in QL level and verify the association between variables and initial level and changes in QL in CKD patients undergoing hemodialysis (HD) during a follow-up of 24 months. Materials and methods: The sample consisted of patients undergoing regular HD in the only renal unit in the north of Ceará state, Brazil. We included those older than 18 years who never had kidney transplant and had been under dialysis at for least three months. Hundred and sixty-four patients were submitted to one evaluation and their data composed a transversal analysis. Ninety-two were submitted at least to two evaluations and were studied by longitudinal analysis. At baseline we collected demographic, clinical and laboratory data; classified the patients according to comorbidity by the Khan index; and submitted them to the SF-36 questionnaire in order to measure QL. Every year the patients were re-evaluated with laboratory tests and submitted again to the SF-36. Linear regression by the stepwise method was used to estimate the correlation between variables and initial level of QL. Change in QL level was detected by analysis of variance using co-variables (ANCOVA), considering the initial and final scores, and by the monthly variation rate (final minus initial score divided by number of months of follow-up). Continuous variables were tested for their association with change in QL by linear regression, and the categorical variables were stratified according to monthly variation rate into three groups: improving, worsening, and no change. Results: QL level improved with respect to Social functioning (63.8 vs. 75.0; p=0.001), Role-emotional (39.7 vs. 63.1; p<0.001) and Mental health (63.1 vs. 69.0; p=0.009). Among low comorbidity patients, besides improvement in these dimensions, there was improvement in Physical functioning (56.7 vs. 63.5; p=0.014) and Bodily pain (56.7 vs. 66.5; p=0.009). Age and albumin were strong correlators due to the initial QL level. Age was negatively associated with all eight QL dimensions: Physical functioning (r=-0,312; p<0,001), Role-physical (r=-0,262; p<0,001), Bodily pain (r=-0,157; p=0,049), General health (r=-0,232; p=0,003), Vitality (r=-0,298; p<0,001), Social functioning (r=-0,293; p=<0,001), Role-emotional (r=-0,260; p=0,001) and Mental health (r=-0,217; p=0,006). Albumin was positively associated with: Physical functioning (r=0,218; p=0,006), Bodily pain (r=0,276; p<0,001), General health (r=0,268; p<0,001), Vitality (r=0,270; p<0,001) and Social functioning (r=0,250; p=0,001). Age and creatinine level were associated with changes in QL estimated by monthly variation rate. Age was negatively associated with Bodily pain (r=-0,031; p=0,024), responsible for 9.0% of its variation, and creatinine was positively correlated with General health (r=0,096; p=0,040), responsible for 4.6% in its variation. More women than men worsened in Physical functioning [19 (50.0%) vs. 11 (21.2%); p=0.006]. Conclusions: There was improvement in mental aspects of QL among the patients. This improvement should be seen as a favorable factor to implement interventions aimed at the physical aspects of QL, with special attention to women and high-grade comorbidity patients. Ageing and low level of the laboratory markers related to nutritional status (albumin and creatinine) should be considered as risk markers of poorer QL level.