Non-Medical Risk Factors as Avoidable Determinants of Excess Mortality in Children with Chronic Kidney Disease. A Prospective Cohort Study in Nicaragua, a Model Low Income Country.

BACKGROUND: The widely recognized clinical and epidemiological relevance of the socioeconomic determinants of health-disease conditions is expected to be specifically critical in terms of chronic diseases in fragile populations in low-income countries. However, in the literature, there is a substantial gap between the attention directed towards the medical components of these problems and the actual adoption of strategies aimed at providing solutions for the associated socioeconomic determinants, especially in pediatric populations. We report a prospective outcome study on the independent contribution and reciprocal interaction of the medical and socioeconomic factors to the hard end-point of mortality in a cohort of children with chronic kidney disease in Nicaragua. METHODS AND FINDINGS: Every child (n = 309) diagnosed with chronic kidney disease (CKD) and referred to the tertiary unit of Pediatric Nephrology in Managua (Nicaragua) from a network of nine hospitals serving 80% of the country's pediatric population was registered between January 2005 and December 2013. The three main socioeconomic determinants evaluated were family income, living conditions and the family's level of education. Further potential determinants of the outcomes included duration of exposure to disease, CKD stage at the first visit as suggested by the KDOQI guidelines in children, the time it took the patients to reach the reference centre and rural or urban context of life. Well-defined and systematically collected medical and socioeconomic data were available for 257 children over a mean follow-up period of 2.5±2.5 years. Mortality and lost to follow-up were considered as outcome end-points both independently and in combination, because of the inevitably progressive nature of the disease. A high proportion (55%) of children presented in the advanced stages of CKD (CKD stage IV and V) at the first visit. At the end of follow-up, 145 (57%) of the 257 cohort children were alive, 47 (18%) were lost to follow-up and 65 (25%) had died. Cox regression analysis showed an independent contribution to mortality of CKD stage at diagnosis and of level of education, with overlapping HR values (HR and 95%CI: 2.66; 1.93-3.66 and 2.72; 1.71-4.33, respectively). CONCLUSIONS: The unfavourable socioeconomic and cultural background of the pediatric study cohort and the severity of kidney damage at diagnosis were the key determinants of the clinical risk conditions at baseline and of the mortality outcome. Long-term structural interventions on such backgrounds must be adopted to assure effectiveness of medical care and to assure an earlier diagnosis of CKD in these patients. The translation-extension of our results is currently underway with an agenda which includes: 1) better integration of chronic pediatric conditions into primary care strategies to promote prevention and early timely referral; 2) the consideration of socioeconomic conditions as a mandatory component of the packages of best-care; 3) the formulation and flexible adaptation of guidelines and educational programs, based on the information generated by a context-specific, epidemiological monitoring of needs and outcomes, guaranteed by an effective database.

Impact of global economic disparities on practices and outcomes of chronic peritoneal dialysis in children: insights from the International Pediatric Peritoneal Dialysis Network Registry.

UNLABELLED: BACKGROUND, OBJECTIVES, AND METHODS: The number of patients on chronic peritoneal dialysis (CPD) is increasing rapidly on a global scale. We analyzed the International Pediatric Peritoneal Dialysis Network (IPPN) registry, a global database active in 33 countries spanning a wide range in gross national income (GNI), to identify the impact of economic conditions on CPD practices and outcomes in children and adolescents. RESULTS: We observed close associations of GNI with the fraction of very young patients on dialysis, the presence and number of comorbidities, the prevalence of patients with unexplained causes of end-stage kidney disease, and the rate of culture-negative peritonitis. The prevalence of automated PD increased with GNI, but was 46% even in the lowest GNI stratum. The GNI stratum also affected the use of biocompatible peritoneal dialysis fluids, enteral tube feeding, calcium-free phosphate binders, active vitamin D analogs, and erythropoiesis-stimulating agents (ESAs). Patient mortality was strongly affected by GNI (hazard ratio per $10 000: 3.3; 95% confidence interval: 2.0 to 5.5) independently of young patient age and the number of comorbidities present. Patients from low-income countries tended to die more often from infections unrelated to CPD (5 of 9 vs 15 of 61, p = 0.1). The GNI was also a strong independent predictor of standardized height (p < 0.0001), adding to the impact of congenital renal disease, anuria, age at PD start, and dialysis vintage. Patients from the lower economic strata (GNI < $18 000) had higher serum parathyroid hormone (PTH) and lower serum calcium, and achieved lower hemoglobin concentrations. No impact of GNI was observed with regard to CPD technique survival or peritonitis incidence. CONCLUSIONS: We conclude that CPD is practiced successfully, albeit with major regional variation related to economic differences, in children around the globe. The variations encompass the acceptance of very young patients and those with associated comorbidities to chronic dialysis programs, the use of automated PD and expensive drugs, and the diagnostic management of peritonitis. These variations in practice related to economic difference do not appear to affect PD technique survival; however, economic conditions seem to affect mortality on dialysis and standardized height, a marker of global child morbidity.