CRIC-Visceral Adiposity and Physical Fitness in Chronic Kidney Disease
Condition: Renal Insufficiency, Chronic; Obesity
MeSH terms: Renal Insufficiency, Chronic; Renal Insufficiency
Study type: Observational

Summary: 
      Obesity and chronic kidney disease (CKD) are major public health problems. In contrary to
      observations in general population, higher body mass index in those with pre-existing CKD is
      associated with lower mortality. Chronic Renal Insufficiency Cohort (CRIC) is an ongoing
      observational study to examine the consequences of CKD with a particular focus on
      cardiovascular illness like myocardial infarction (heart attack) and stroke. Among CRIC study
      participants, the investigators propose to obtain visceral and subcutaneous adiposity and
      physical fitness measures and study its associations with patient-centered outcomes. This
      study will help the investigators understand the independent and combined effects of visceral
      adiposity and physical fitness on cardiovascular disease, renal disease progression and death
      among those with CKD. Further, it will identify mechanisms that could be targeted to reduce
      the detrimental effects of visceral adiposity in those with kidney disease.
    

Detailed description: 
      Obesity and chronic kidney disease (CKD) are major public health problems. Obesity
      independent of its relationship with diabetes and hypertension is associated with the
      development and progression of kidney disease. However, higher body mass index (BMI) in those
      with pre-existing CKD is associated with lower mortality (obesity paradox). This may be due
      to the inability of BMI to differentiate fat mass and muscle mass, which may have opposite
      relationship with cardiovascular disease and death. Body fat distribution is a major factor
      of metabolic health with metabolic abnormalities correlating better with visceral than
      subcutaneous adipose tissue. Further, higher fitness levels among those with higher BMI is
      associated with a lower prevalence of cardiovascular risk factors and mortality that might
      explain this obesity paradox. Therefore, among Chronic Renal Insufficiency Cohort (CRIC)
      study participants, the investigators propose (a) to examine whether visceral adiposity is
      associated with a higher incidence of composite outcomes (i.e., mortality, cardiovascular
      events, end stage renal disease, and 50% decline in estimated glomerular filtration rate),
      (b) to determine if physical fitness modifies the association between adiposity and outcomes,
      and (c) to study whether visceral adiposity and physical fitness are associated with altered
      adipokine profile, inflammation, insulin resistance, and oxidative stress. The study proposes
      to enroll 526 patients with varying degrees of kidney disease from 7 clinical centers
      involved in the CRIC study. Visceral adiposity will be measured by magnetic resonance imaging
      (MRI) of the abdomen using a standard protocol, and physical fitness will be measured using a
      400 m walk test during routine CRIC study visits. Results from this study will help the
      Investigators understand the independent and combined effects of visceral adiposity and
      physical fitness on cardiovascular disease and kidney disease progression among CKD patients.
      This study will also highlight potential pathways that mediate the relationship between
      adiposity and outcomes, which will become the focus of future therapeutic investigations in
      CKD.
    

Observational model: Cohort
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        Must be participant in Prospective Cohort Study of Chronic Renal Insufficiency (CRIC). CRIC
        participants are a racially and ethnically diverse group of adult patients with
        mild-to-moderate CRI.
      
Biospecimen description: 
      serum, blood
    
Keywords: CKD, chronic kidney disease, CRIC