[New diagnostic criteria and classification of diabetes mellitus]

World Health Organisation (WHO) has recently proposed new diagnostic criteria and classification of diabetes mellitus. A major change in diagnostic criteria is lowering of diagnostic fasting plasma glucose level: level of 7.0 mM/L or more in two separate samples is sufficient for the diagnosis. Diagnostic criteria for plasma glucose in 120-min. of oral glucose tolerance test are unchanged. Newly recommended fasting level seems to correlate better with 120-min. value and to be a good marker of increased cardiovascular risk. The new classification describes impaired glucose regulation with two stages: impaired fasting glycaemia (plasma glucose of 6.1-7.0 mM/L) which is a new category and impaired glucose tolerance. Both subcategories are not real clinical entities, but markers of diabetic and cardiovascular risk. Diabetes mellitus, as a clinical entity, is separated in four classes: type 1, type 2, other specific types and gestational diabetes. Gestational diabetes includes any glucose intolerance in pregnancy. The Croatian Board for Diabetes Mellitus recommends acceptance of these criteria and classification for clinical use in the country and suggests that OGTT be performed for metabolic syndrome detection in cases of impaired fasting glycaemia.