Capillary rarefaction: a missing link in renal and cardiovascular disease?

Area of Science:

• Nephrology
• Cardiology
• Vascular Biology

Background:

• Patients with chronic kidney disease (CKD) face elevated risks of cardiovascular morbidity and mortality.
• Capillary rarefaction, a reduction in blood vessel density, is implicated as both a cause and consequence of CKD and cardiovascular disease.
• Endothelial dysfunction and capillary loss are key pathological features in renal and systemic vasculature.

Purpose of the Study:

• To review the literature on human biopsy studies concerning capillary rarefaction in the context of chronic kidney disease and cardiovascular disease.
• To explore the relationship between renal and systemic capillary rarefaction.
• To emphasize the importance of capillary integrity in managing renal and cardiovascular diseases.

Main Methods:

• Systematic review of published human biopsy studies.
• Analysis of findings from non-invasive measurements of capillary density.
• Synthesis of evidence linking capillary rarefaction to CKD and cardiovascular risk factors.

Main Results:

• Renal capillary rarefaction occurs independently of the cause of declining renal function.
• Glomerular hypertrophy may indicate early endothelial dysfunction; peritubular capillary loss is associated with advanced renal disease.
• Systemic capillary rarefaction is detectable in individuals with albuminuria (early CKD) and in those with cardiovascular risk factors, affecting various tissues.

Conclusions:

• Capillary rarefaction is a significant finding in both CKD and cardiovascular disease, affecting renal and systemic vasculature.
• The causal relationship and temporal sequence between renal and systemic capillary rarefaction remain unclear, necessitating further investigation.
• Maintaining capillary integrity is crucial for preventing and managing renal and cardiovascular diseases.