Obesity phenotype and patient-reported outcomes in moderate and severe chronic kidney disease: a cross-sectional study from the CKD-REIN cohort study

Purpose To evaluate the association between obesity phenotypes and health-related quality of life (HRQoL) in non-dialysis-dependent CKD patients. Methods Data from the national CKD-REIN cohort which included 3033 patients with stage 3-4 CKD were used. Patients were divided into three groups: non-obese (NO) patients (BMI < 30 kg/m(2)), metabolically healthy obese (MHO) (BMI >= 30 kg/m(2) and <= 1 criterion NCEP/ATP III), and metabolically unhealthy obese (MUO) (BMI >= 30 kg/m(2) and 2 criteria NCEP/ATP III). HRQoL was measured by the KDQOL-36 which comprised three disease-specific dimensions: symptoms, effects, and burden and two summaries scores: physical (PCS) and mental (MCS). We used a mixed effect model with adjustment on sociodemographic characteristics and comorbidities. Results A total of 2693 patients completed the self-administered questionnaires. MHO patients accounted for 3.4% of the cohort and for 12% of obese patients. In the NO group, average HRQoL scores were 77.215.9 for symptoms, 83.5 +/- 16.5 for effects, 76.8 +/- 22.7 for burden, 43.5 +/- 9.7 for PCS, and 47.9 +/- 7.0 for MCS. In the multivariate analysis, scores were similar in MHO and NO patients, but significantly different with those in MUO patients: symptoms (-0.7; p = 0.71 vs. -3.0; p = 0.0025), effects (+1.2; p = 0.57 vs. -4.3; p < 0.0001), burden (+2.7; p = 0.31 vs. -3.6; p = 0.0031), and PCS (-0.6; p = 0.58 vs. -4.3; p < 0.0001). MCS was not associated with obesity phenotypes. Conclusions This study demonstrated an association between obesity phenotypes and QoL in non-dialysis-dependent CKD patients. MUO patients had worse QoL than NO and MHO patients even after adjustment on comorbidities.