Introduction: This systematic literature review analyzed published evidence on IgA nephropathy (IgAN), focusing on US epidemiology, health-related quality of life (HRQoL), and economic burden of illness.Methods: Using Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, Embase®, MEDLINE®, Cochrane, and Econlit (January 2010 to June 2020) were searched, along with relevant congresses (2017)(2018)(2019)(2020).Results: Of 123 epidemiologic studies selected for data extraction, 24 reported IgAN diagnosis rates ranging from 6.3% to 29.7% among adult and pediatric patients undergoing renal biopsy, with all reported US rates <15%. No US studies reported IgAN prevalence. A meta-analysis of US studies calculated an annual incidence of 1.29/100 000 people, translating to an annual US incidence of 4236 adults and children. Relative to Europe, the United States had more patients diagnosed with IgAN in later chronic kidney disease stages. US rates of transition to end-stage renal disease (ESRD) ranged from 12.5% to 23% during 3-3.9 years of observation, rising to 53% during 19 years of observation. Across 8 studies reporting HRQoL, pain and fatigue were the most reported symptoms, and patients consistently ranked kidney function and mortality as the most important treatment outcomes. Patients with glomerulopathy reported worse mental health than healthy controls or hemodialysis patients; proteinuria was significantly associated with poorer HRQoL and depression.
Conclusion:While economic evidence in IgAN remains sparse, management of ESRD is a major cost driver. IgAN is a rare disease where disease progression causes increasing patient burden, underscoring the need for therapies that prevent kidney function decline and HRQoL deterioration while reducing mortality.
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JOURNAL OF HEALTH ECONOMICS AND OUTCOMES RESEARCHthe potential for underdiagnosis or diagnostic delay in regions with limited screening, particularly for patients without severe symptoms. 2,3 It has been reported that up to 50% of patients with IgAN progress to ESRD within 20 years of clinical presentation. 4,[10][11][12] Risk factors for progression to ESRD include persistent proteinuria, hypertension, and reduced glomerular filtration rate. 6,9 Consequences of advanced CKD and kidney failure in IgAN include requirement for dialysis or transplantation, poor health-related quality of life (HRQoL), and increased mortality. 3,4,[13][14][15] Symptoms of CKD and adverse events due to dialysis have a substantial impact on HRQoL, daily living, and ability to work. 13,14 Moreover, patients who undergo transplantation remain at risk of IgAN recurrence due to the underlying pathophysiology. 16 All GN subtypes have the potential to recur post-transplantation, with the prevalence of GN recurrence between 3% and 15%. 17 In addition, kidney transplant patients must deal with the associated life-long regimen of medications to reduce the risk of graft rejection, lifestyle changes, self-care, and medical appointments required to maintain t...