German Nephrology Society issues health warnings for marathon runners

The German Society of Nephrology (DGfN) is advising individuals preparing for extreme endurance activities, such as the Berlin Marathon on September 27, to undergo kidney function testing. This recommendation specifically targets people with hypertension, diabetes mellitus, cardiovascular diseases, or pre-existing kidney damage, as these conditions increase the risk of chronic kidney disease (CKD).

Medical experts warn that extreme physical exertion combined with heat, dehydration, and the use of non-steroidal anti-inflammatory drugs (NSAIDs)—such as ibuprofen, diclofenac, or naproxen—can significantly raise the risk of acute kidney injury. To assess organ function, the DGfN suggests monitoring the estimated glomerular filtration rate (eGFR) via blood tests and the albumin-to-creatinine ratio (UACR) via urine tests.

While endurance sports are generally beneficial for healthy, well-prepared individuals, those in high-risk groups should be aware that kidney issues often remain asymptomatic for long periods. Professor Sylvia Stracke of University Medicine Greifswald noted that those with hypertension or diabetes carry an increased risk of previously undetected kidney damage.