Initial D: First Stage Episode 12
There were 53 coded DKA episodes (41 first episodes, 12 recurrences), of which 19 (35.8%) were incorrectly coded, 9 (17.0%) had possible DKA and 25 (47.2%) had confirmed/probable DKA. Of this latter group, 44% had type 1 diabetes, 32% had type 2 diabetes, 12% had latent autoimmune diabetes of adults (LADA) and 12% had secondary diabetes. The overall incidence of confirmed/probable DKA (95% CI) was 35.6 (23.0 to 52.6)/10 000 person-years (178.6 (85.7 to 328.5)/10 000 person-years for type 1 diabetes, 13.3 (5.7 to 26.1)/10 000 person-years for type 2 diabetes, 121.5 (33.1 to 311.0)/10 000 person-years for LADA and 446.5 (92.1 to 1304.9)/10 000 person-years for secondary diabetes). Baseline ln(fasting serum C-peptide) (inversely), glycated hemoglobin and secondary diabetes predicted both incident first confirmed/probable DKA episode and the frequency of DKA (p
Initial D: First Stage Episode 12
During a meanSD 4.11.1 years of follow-up to death or end-2013, there were 41 recorded episodes of first DKA during the follow-up period in FDS2 participants including one coroner-adjudicated death attributed to DKA. Of these 41 cases, 17 (41.5%) were confirmed and 1 (2.4%) probable based on clinical/laboratory data, representing a total of 18 (43.9%) confirmed/probable cases. There were 16 cases (39.0%) that were incorrectly coded as DKA and, in 4 of these who had subsequent additional coded DKA episodes during the period of follow-up, none of these hospitalizations met the criteria for DKA. A further seven participants (17.1%; mean age 62.117.2 years, 57.1% males) could not be categorized because of insufficient data and were not considered further in the present analysis.
The characteristics of FDS2 participants who did not experience an episode of DKA during follow-up and those of the 18 confirmed/probable cases are summarized in table 1. The confirmed/probable cases had a younger age at diagnosis, a longer diabetes duration and a lower BMI than those who did not develop DKA. They were more likely to have forms of diabetes other than type 2 apart from monogenic diabetes, and were more likely to be insulin-treated as a result. They also had a higher glycated hemoglobin (HbA1c), a lower serum C-peptide and a greater likelihood of prior severe hypoglycemia than those without DKA during follow-up. They were more likely to have at least stage 3 renal impairment.
Of the 1725 participants, 25 (1.4%) had at least one missing value among the clinically plausible variables of interest. Age at diabetes diagnosis, BMI, HbA1c, serum C-peptide, insulin use and eGFR had between one and eight missing values that were imputed. In a Cox proportional hazards model, the independent predictors of time to first episode of DKA were the serum C-peptide (inversely), a diagnosis of secondary diabetes and HbA1c (all p
Eight participants (0.5% or 44.4% of those with a first incident DKA episode during follow-up) had one or more further hospitalizations coded as DKA. Of these 12 additional events, 5 were confirmed in three participants and 2 were categorized as probable in two participants (58.3% confirmed/probable cases) after chart review, 3 (25.0%) were incorrectly coded as DKA and 2 (16.7%) could not be categorized because of insufficient data. Of the five with recurrent confirmed/probable DKA, one had type 1 diabetes, two had type 2 diabetes, one had LADA and one had secondary diabetes.
When combined with the first DKA episodes, the overall percentages of the 25 confirmed/probable cases in 1725 FDS2 participants during 7022 person-years of follow-up to death or end-December 2013 (whichever came first), DKA cases by type of diabetes were 32% type 2, 44% type 1, 12% LADA and 12% secondary diabetes. The overall incidence rate (95% CI) was 35.6 (23.0 to 52.6)/10 000 person-years. When subdivided by diabetes type, the overall incidence rates were 13.3 (5.7 to 26.1)/10 000 person-years for type 2 diabetes, 178.6 (85.7 to 328.5)/10 000 person-years for type 1 diabetes, 121.5 (33.1 to 311.0)/10 000 person-years for LADA and 446.5 (92.1 to 1304.9)/10 000 person-years for secondary diabetes including the one fatal case.
All participants were reviewed by the multidisciplinary diabetes team during hospitalization. When there was both a clear precipitating factor (infection in many cases, but a faulty insulin pump in one and accidental omission of insulin treatment by nursing home staff in another) and the admission HbA1c indicated acceptable prior glycemic control, diabetes treatment regimens were not altered, but relevant information including that relating to sick day management was provided before discharge. Adherence was emphasized in those in which this was considered to be a contributing factor, and insulin regimens were intensified in those whose HbA1c was above an appropriate target. This included participants with type 2 diabetes, all of whom were insulin-treated at the time of their first and subsequent DKA episodes.
In a recent US review of electronic hospital data, 11 of 32 (34%) of admissions were not validated by endocrinologist review of biochemical and other data as DKA despite DKA being coded as the diagnosis.6 This is similar to the incorrect coding rates of 39.0% for initial episodes and 41.7% for recurrences in the present study, although we also had seven participants (17.1%) with incomplete data for the initial episode. In most of these latter cases there was no documentation of plasma or urinary ketone concentrations, but other details required for diagnostic confirmation such as the plasma lactate (especially in metformin-treated participants with renal impairment31) may not have been available. These considerations highlight the necessity of medical record validation to correctly ascertain cases of DKA for healthcare quality assessment and planning purposes. In a similar vein, coding of type of diabetes in cases of DKA in the US study was incorrect in one in six cases.6 There are data suggesting that individuals with type 2 diabetes and DKA require higher daily total insulin doses, larger replacement fluid volumes and greater potassium supplementation to resolve their DKA than are used in type 1 diabetes.5 Accurate ascertainment of the type of diabetes could, therefore, influence the nature of initial management, although the effect of more intensive fluid resuscitation and insulin administration on prognosis in DKA complicating type 2 diabetes remains unknown. 041b061a72