Prevalence refers to the presence of a health-related condition (e.g., CKD) in a particular population at a specific point in time (point prevalence) or, less frequently, during a specific period (period prevalence); it may be expressed as a count (number of prevalent cases) or as the proportion of cases in the population (prevalence of the condition).

Without awareness and knowledge of chronic kidney disease (CKD in the general and medical communities, the burden of CKD (prevalence and incidence) cannot be diminished. Early awareness of CKD could slow progression to kidney failure and mitigate associated complications and outcomes.

Identification of those at risk for development of CKD forms an integral part of a CKD surveillance system. First, examining changes in the burden of risk factors for CKD can help predict the potential future burden of CKD. For example, if the prevalence of an important risk factor is rising, it is likely that the prevalence of CKD will rise accordingly. Second, assessing the burden of risk factors can also help identify which interventions are likely to have the most impact on reducing the burden of CKD. Early intervention in those with risk factors may help prevent or delay the onset of CKD, or in the case of established CKD, help slow progression or reduce related morbidity and mortality.

CKD is characterized by a high burden of comorbidities such as cardiovascular disease, obesity, diabetes, hypertension, and others. Many of these conditions can be both a cause and consequence of CKD. In the presence of CKD, outcomes among patients with other comorbidities are typically worse than in the absence of CKD.  The most important consequences of CKD include renal disease progression that has the potential to lead to end stage renal disease (ESRD), or death.

Assessment of the processes of care and practice patterns related to the detection and management of CKD is an integral part of a national CKD surveillance system. Tracking the processes of care related to CKD could be instrumental in facilitating the implementation of early diagnostic steps and institution of appropriate therapies to either prevent the development of disease or slow progression of established disease. Examination of administrative health care data is a cost-efficient method for tracking processes of care in the practice setting.

Although the prevalence of CKD and its risk factors in U.S. children and adolescents is expected to be far lower than that in the adult population, capturing information about this population in a CKD surveillance system is of utmost importance, as these children and adolescents will likely become part of the at-risk adult population, or even the adult CKD population, over time. Additionally, children and adolescents with CKD differ in many important ways (in both cause and outcomes of disease) and thus should be examined separately from their adult counterparts.

Recipients of solid organ transplants have been recognized as being at very high risk for developing CKD. Hence, they regarded here as a “special population.” Fortunately, data from the comprehensive national Scientific Registry for Transplant Recipients (SRTR) are a rich source of information on this topic.

Traditional topics considered for inclusion in the surveillance system cover areas of chronic kidney disease that are widely accepted and of direct relevance to public health based upon peer-reviewed research published over time. The section on emerging topics is designed to bring to light recent advances in chronic kidney disease relevant to public health surveillance of CKD. While it currently focuses on risk factors – both modifiable and non-modifiable, it is intended in the future to include other topics that provide novel insights into the burden of kidney disease, its geographic distribution and temporal trends, advances in processes of care (both diagnostic and therapeutic), and newer insights into awareness of CKD, associated health outcomes or health system capacity. These emerging topics could eventually evolve into more established concepts warranting formal attention in a CKD surveillance system and potentially even have widespread population health management, prevention and/or policy implications.