Nine patients were inadvertently omitted from the 2000-2001 follow-up visit, changing the total from 822 to 831. This affected the text, and values in Figure 1, Table 2 and Table 4. Acronyms indicating normal and impaired glucose tolerance (NGT and IGT) were used incorrectly when normal and impaired glucose tolerance (NGM and IGM) were intended. This affected the text, Figure 1 and Figure 2. The authors have added a link to the Hoorn studies website for up to date versions of Tables 2, 3 and 4, including new visits and new variables. The article has been corrected.