Mortality Following Diabetic Ketoacidosis Greater in T2D vs T1D

The rate of mortality resulting from diabetic ketoacidosis (DKA) was found to be increased in patients with type 2 diabetes (T2D) compared with those with T1D, according to the results of a retrospective cohort study published in The Journal of Investigative Medicine. Patients with T2D stayed in the hospital longer with commensurate increased healthcare costs and had an increased likelihood of developing sepsis compared with patients with T1D. 

Shaka and colleagues conducted this study using information regarding 245,170 patients with a primary discharge diagnosis of DKA that was gathered from the Nationwide Inpatient Sample (NIS) database from January 1, 2016, to December 31, 2017. The NIS database accumulates information based on ICD-10 billing and coding from hospital inpatient stays and covers more than 97% of the US population. Of these patients, 225,495 (92%) had T1D and DKA, and 19,675 (8%) had T2D and DKA. The study excluded patients younger than 18 years of age, patients who had an unspecified type of diabetes, and patients who had DKA listed as a secondary diagnosis.

The primary outcome measure compared inpatient mortality rates between T1DM and T2DM in adults hospitalized with DKA. Secondary outcomes compared adverse events in organ systems that occurred as a result of DKA such as rate of sepsis, septic shock, acute kidney failure (AKI), acute respiratory failure (ARF), deep vein thrombosis (DVT), pulmonary embolism (PE), mean length of hospital stay (LOS), and mean total hospital charges (THC).

Patients with T1D and DKA admitted to the hospital were significantly younger, with a mean age of 34.4 years vs 51.1 years for the patients with T2D. There also was a higher proportion of women in the T1D group (51.5%) compared with the T2D group (46.5%). Compared with patients with T1D, patients with T2D had an increased incidence of comorbidities, specifically hypertension (45.1% vs 24.5%, P <.001), chronic kidney disease (10.9% vs 9.1%, P <.001), and congestive heart failure (7.4% vs 3.1%, P <.001).

From 2016 to 2017, there were 650 (0.265%) deaths related to DKA. Despite consisting of only 8% of the patients in the study, patients in the T2D group had a higher adjusted odds ratio (aOR) of inpatient mortality (1.04% vs 0.20%, aOR 2.09; 95% CI, 1.36-3.22, P =.001) compared with patients in the T1D group. Patients with T2D also were more likely to go into septic shock (aOR 2.02; 95% CI, 1.16-3.52, P =.013) compared with those with T1D group. There was also a higher prevalence of AKI among patients with T2D, as the incidence of AKI is higher in patients with diabetes who develop sepsis and go into septic shock. Hospital costs for the T2D group were higher than those for the T1D group ($36,600 vs $27,900, aOR $3800; 95% CI, 1900-5700, P <.001). There were no statistically significant differences in the other secondary outcome measures of mean LOS, ARF, DVT, or PE.

Strengths of this study included the large sample size, the ethnic diversity of patient demographics, and the exploration of outcome-oriented aspects of inpatient admissions for DKA in the United States.

Limitations of this study included a lack of information regarding severity of disease progression and time of initial diagnosis, lack of randomization associated with retrospective studies, possible ICD-10 coding errors, and potential repeat hospitalizations of the same person in the data set because NIS reports data based on DKA hospitalizations rather than on individual patients.

The clinical significance of this study is to promote awareness of DKA as a cause of increased mortality in patients with T2D compared with those with T1D. This study provided necessary information for the development and implementation of a risk-stratification system in clinical practice to predict and prevent adverse outcomes in patients with T2D who are hospitalized with DKA.

Reference

Shaka H, Wani F, El-Amir Z, et al. Comparing patient characteristics and outcomes in type 1 versus type 2 diabetes with diabetic ketoacidosis: a review and a propensity-matched nationwide analysis. J Investig Med. Published online May 10, 2021. doi:10.1136/jim-2021-001901