1 Background
Chronic kidney disease (CKD) was defined as an abnormality of kidney
structure or function that can adversely affect health1. CKD has become an
important public health problem, and is associated with high rates of
disability and mortality. In 2016, global years lived with disability
among men age 15 to 49 years of age with CKD was 0.81% and deaths were
1.94% 2. The prevalence
of CKD (stages 1-5) is estimated to be 3% to 18% globally3, and around 8.6% for
adult males and 9.6% for adult females in high-incomes countries4. A cross-sectional
survey based on a nationally representative sample of Chinese adults
estimated that around 120 million persons have CKD, with a prevalence of
CKD of around 11% 5.
Persons with CKD have a reduced life expectancy due to increased
cardiovascular disease and increased all-cause mortality6. CKD and associated
morbidities are important drivers of increased health care costs7. Importantly, in many
patients CKD is not diagnosed until it is in a late stage8. Thus, it is important
to identify factors that may predict the development of CKD so that
early interventions may be given to prevent or delay its development.
The association of glucose metabolism and the development of CKD has
been extensively investigated over the past decade. Diabetes is the
leading cause of CKD, and up to one-third of adults with newly diagnosed
diabetes already have CKD9. Diabetes is thought
to be responsible for almost 40% of new cases of CKD10. Pre-diabetes also
increases the risk of developing CKD11,12.
Diabetes and pre-diabetes diagnosed according to an elevated fasting
plasma glucose (FPG) and/or 2-hour oral glucose tolerance test (OGTT)
and/or elevated hemoglobin (HbA1c) based on World Health Organization
(WHO) 13 or American
Diabetes Association (ADA)14 criteria are closely
related with the development of CKD. Several studies11,15,16have shown positive associations between CKD and FPG, OGTT, and HbA1c,
as well as fasting insulin level, homeostasis model assessment of
insulin resistance (HOMA-IR), and HOMA-β. A wide body of evidence
supports that abnormalities of glucose metabolism are related with the
development if CKD. However, associations have mainly been identified
through cross-sectional studies; longitudinal data associating indices
of glucose metabolisms and CKD are limited. In addition, few studies
have examined if any single index of glucose metabolism is superior for
predicting the development of CKD.
Thus, the purpose of this study was to use longitudinal data to
investigate associations between glucose metabolism indices and CKD in a
Chinese population, and determine which index is superior for predicting
CKD.