Mediators of the Association Between Low Socioeconomic Status and Chronic Kidney Disease in the United States

Abstract

Using data collected from 9,823 participants in the 2007-2008 and 2009-2010 cycles of the National Health and Nutrition Examination Survey, we formally investigated potentially modifiable factors linking low socioeconomic status (SES) to chronic kidney disease (CKD) for their presence and magnitude of mediation. SES was defined using the poverty income ratio. The main outcome was CKD, defined as estimated glomerular filtration rate <60 mL/minute/1.73 m(2) (using the Chronic Kidney Disease Epidemiology Collaboration equation) and/or urinary albumin:creatinine ratio ≥30 mg/g. In mediation analyses, we tested the contributions of health-related behaviors (smoking, alcohol intake, diet, physical activity, and sedentary time), comorbid conditions (diabetes, hypertension, obesity, abdominal obesity, and hypercholesterolemia), and access to health care (health insurance and routine health-care visits) to this association. Except for sedentary time and diet, all examined health-related behaviors, comorbid conditions, and factors related to health-care access mediated the low SES-CKD association and contributed 20%, 32%, and 11%, respectively, to this association. In race/ethnicity-specific analyses, identified mediators tended to explain more of the association between low SES and CKD in non-Hispanic blacks than in other racial/ethnic groups. In conclusion, potentially modifiable factors like health-related behaviors, comorbid conditions, and health-care access contribute substantially to the association between low SES and CKD in the United States, especially among non-Hispanic blacks.

Risk Factors for Rapid Kidney Function Decline Among African Americans: The Jackson Heart Study (JHS)

“…24 Mediators of low cosioeconomic status and CKD prevalence appear to be related to modifiable risk factors such as smoking, alcohol use, diet, and physical activity, which are reported to contribute 20% of risk variance, while comorbid conditions contribute 30%, and access to care 11%. 25 The current study found that education was a potent predicator of rapid kidney function decline, while income and access to care trended towards an association.…”

Low socio‐economic status adversely effects dialysis survival in Australia

“…Many of these factors are complex and varied, and a large number of interrelated factors likely contribute. Work from the USA among people with chronic kidney disease has reported potentially modifiable factors such as health‐related behaviours (smoking, alcohol and physical activity), co‐morbid conditions and healthcare access (health insurance and health visits) substantially explain the association between SES and chronic kidney disease . Determining future actions to reduce the gap needs further work.…”

Individual Income Status Correlates with Chronic Kidney Disease in Japan beyond Metabolic Risk Factors: Cross Sectional Study

“…In previous reports, many people with low SES have an unhealthy lifestyle [21] [23] [24]. Priya et al showed that proportion of participants with unhealthy lifestyles, such as high alcohol intake and physical inactivity were higher in participants with low SES [25]. It may be that metabolic risks, such as DM, DL, HT and obesity, in addition to unhealthy lifestyle factors, are mediators of the association between low SES and CKD [25].…”

“…Priya et al showed that proportion of participants with unhealthy lifestyles, such as high alcohol intake and physical inactivity were higher in participants with low SES [25]. It may be that metabolic risks, such as DM, DL, HT and obesity, in addition to unhealthy lifestyle factors, are mediators of the association between low SES and CKD [25]. In summary, unhealthy lifestyles and metabolic risk factors may develop due to low SES, resulting in CKD.…”

“…In this regard, it was interesting that we found a relationship between income and CKD, even in Japan, where healthcare is easy to access. In a past study, health insurance and routine healthcare services were examined as potential meditators of the SES-CKD association, as were health-related behaviors and comorbid conditions [25]. Factors related to healthcare access contributed 11% to the SES-CKD association, indicating that the contribution of healthcare factors is greater than that of health-related behaviors such as smoking or alcohol intake.…”