Proteinuria is the medical term for the abnormal presence of excess protein in urine, often reflecting damage to the kidneys' filtering units, the glomeruli. It may be quantified as microalbuminuria, overt proteinuria, or nephrotic-range protein loss, depending on levels. Causes include diabetic nephropathy, hypertensive kidney disease, glomerulonephritis, autoimmune disorders, and certain medications. Persistent proteinuria is a key marker of chronic kidney disease and is associated with higher risks of cardiovascular events and progression to renal failure. For life insurance underwriting, the degree and cause of proteinuria are crucial factors in determining mortality risk, acceptable ratings, or the need for postponement until stability is documented.

Underwriters reviewing applications note when attending physician statements or lab reports mention proteinuria, microalbuminuria, or nephrotic syndrome. They evaluate the underlying diagnosis, blood pressure control, concurrent diabetes, and the trend in kidney function tests. Mild, stable proteinuria in well-controlled patients may be insurable with moderate ratings, while progressive disease or heavy protein loss often leads to postponement or decline. Advisors can add value by obtaining recent nephrology notes, medication lists, and specialist assessments before submitting a case. Explaining that proteinuria reflects systemic vascular and kidney stress helps clients understand why underwriters weigh it heavily when evaluating long-term risk.