#5300 HUMANISTIC BURDEN OF RARE KIDNEY DISEASES: UNDERSTANDING THE IMPACT OF IGAN AND FSGS ON PATIENTS AND CARE-PARTNERS STUDY (HONUS): A US IGAN RESULTS UPDATE
Authors: Szklarzewicz Justyna , Bensink Mark 
Published: June 2023

Abstract

Background and Aims
While immunoglobulin A nephropathy (IgAN) has been shown to be associated with clinical and economic burden, the humanistic burden associated with IgAN is less understood. HONUS is a multi-national, cross-sectional survey study to evaluate the humanistic burden associated with rare kidney diseases, including IgAN, from the patient and caregiver perspectives in the US and Europe.

Method
The study recruited adult patients (≥18 years old) with their care-partners and parents/care-partners of youth (8-17 years old) with IgAN or focal segmental glomerulosclerosis (FSGS). Participants completed an online survey with questions on demographic and clinical characteristics, health-related quality of life (HRQoL) (ie, 12-Item Short Form Survey [SF-12]), anxiety and depression (ie, Generalized Anxiety Disorder Assessment [GAD-7], Patient Health Questionnaire [PHQ-9]), most burdensome symptoms, fear and uncertainty for the future, and disease impact on work productivity (ie, Work Productivity and Activity Impairment [WPAI]). The current analysis is based on information from adults with IgAN and their care-partners in the US before September 2022. Descriptive analyses were conducted, with continuous variables summarized using means, medians, and standard deviations (SD), and categorical variables summarized using frequency counts and percentages.

Results
A total of 96 pairs of adults with IgAN and their care-partners in the US were included in the analysis. The mean age of adult patients was 37.5 and the majority were Caucasian (86.5%) and female (53.1%). Median time since diagnosis was 5.6 years. More than half of patients (59.4%) were in chronic kidney disease stage 3 or 4, while 5.2% were in end-stage renal disease and had received a kidney transplant. Hypertension (31.3%), anemia (25.0%), and depression (18.8%) were the most common comorbidities. In terms of HRQoL, patient's mean (SD) SF-12 physical and mental component scores (PCS, MCS) were reported at 46.9 (7.4) and 41.1 (9.1), respectively, reflecting worse HRQoL (lower score) than previously published US general population scores (PCS and MCS of 50 [10]). Moderate and severe anxiety was reported by 28.1% and 1.0% of patients, respectively; moderate, moderately severe, and severe depression was reported by 51.0%, 2.1% and 1.0% of patients, respectively. The most burdensome symptoms reported by patients were constipation (82.3%), lower back pain (79.2%), and bone or joint pain (77.1%). Based on a 4-week recall period, 25.0% of adult patients reported being ‘very much bothered’ or ‘extremely bothered’ by bone or joint pain (22.9% for lower back pain, 10.4% for constipation). Most patients (96.9%) reported feeling fear and uncertainty for the future due to their disease, of which 52.1% reported the frequency of fear and uncertainty to be ‘often’. Among employed patients (72.9%), percent absenteeism was reported in 6.9%, presenteeism in 27.1%, overall work productivity loss in 31.4%, and activity impairment in 36.2% because of IgAN-related reasons. Most paired care-partners (87.5%) were partners of patients, with a mean age of 39.5 years. The mean SF-12 PCS and MCS of care-partners were 50.4 and 43.6, respectively. Moderate anxiety was reported in 13.5% of care-partners, with none reporting severe anxiety; moderate and moderately severe depression was reported in 35.4% and 5.2% of care-partners, respectively. Almost all care-partners (99.0%) reported feeling fear and uncertainty for the future due to the disease of their cared ones, of which 39.6% reported the frequency of this worry to be ‘often’. Among employed care-partners (93.8%), 9.8% reported absenteeism, 27.3% reported presenteeism, 33.2% reported overall work productivity loss, and 31.9% reported activity impairment due to IgAN-related reasons.

Conclusion
Patients with IgAN experience impaired HRQoL, depression, anxiety, and poor productivity, compared to previously reported US general population estimates. This also impacts the HRQoL, in terms of mental components, and productivity of care-partners. Both patients with IgAN and their care-partners also report widespread fear and uncertainty for the future.