More than seven percent of the Dutch population is in the first stages of kidney damage and are therefore at higher risk of getting cardiovascular disease and type 2 diabetes. This can be determined at an early stage by testing the urine for the presence of the protein microalbuminuria.This is one of the results of the PREVEND study (Prevention of Renal and Vascular End-stage Disease). For this study all the inhabitants of the city of Groningen were asked, in 1997, to complete a brief questionnaire and provide morning urine. Of the 41,000 respondents, 8,600 persons were immediately invited for further examination. In 2001 they were screened again. Thanks to the early detection it is possible to start treatment at an early stage, as a result of which expensive treatments and hospital admissions are often no longer needed.