Ketoacidosis at diagnosis of type 1 diabetes in children in northern Finland: temporal changes over 20 years.

OBJECTIVE To study the frequency of diabetic ketoacidosis (DKA) over a 20-year period among children diagnosed with type 1 diabetes in northern Finland. RESEARCH DESIGN AND METHODS The study population comprised 585 patients (328 boys) diagnosed with type 1 diabetes aged <15 years in the Department of Pediatrics, Oulu University Hospital, between 1 January 1982 and 31 December 2001. The data for clinical characteristics were collected retrospectively from the patients' case records. The earlier 10-year period (1982-1991) was compared with the later 10-year period (1992-2001). Two definitions for DKA were used: DKA(i) pH <7.30 or DKA(ii) pH <7.30 and/or bicarbonate <15 mmol/l. RESULTS During the later 10-year period, children less often had DKA at diagnosis [DKA(i) 15.2 vs. 22.4%, P = 0.028, and DKA(ii) 18.9 vs. 29.5%, P = 0.003]. The proportion of young children aged <5 years at diagnosis increased over time, but the frequency of DKA also was lower in this age-group during 1992-2001 compared with the earlier 10-year period [DKA(i) 17.7 vs. 32.1%, P = 0.052, and DKA(ii) 20.3 vs. 42.6%, P = 0.005]. In children aged <2 years at diagnosis, the frequency of DKA remained high during 1992-2001 [DKA(i) 39.1% and DKA(ii) 47.8%]. CONCLUSIONS The overall frequency of DKA in children with newly diagnosed type 1 diabetes decreased over a 20-year period in northern Finland. However, children aged <2 years are still at high risk for DKA at diagnosis.