A simple blood test mismatch linked to kidney failure and death

A major global study suggests that a hidden mismatch between two common blood tests could quietly signal serious trouble ahead. When results from creatinine and cystatin C—two markers used to assess kidney health—don’t line up, the risk of kidney failure, heart disease, and even death appears to rise sharply. Researchers found that this gap is especially common among hospitalized and older patients, and that relying on just one test may miss early warning signs.