Higher mortality and longer length of stay in hospitalized patients with newly diagnosed diabetes.

Aims: We investigated the association between diabetes status at admission and in-hospital outcomes in all hospitalized patients, regardless of the reason for admission.

Methods: All individuals aged 20 years or older who were admitted to Yongin Severance Hospital between March 2020 and February 2022 were included in study. Subjects were categorized into three groups: non-DM, known DM, and newly diagnosed DM, based on medical history, anti-diabetic medications use, and laboratory test. Hospitalization-related outcomes, including in-hospital mortality and length of hospital stay, were compared between groups.

Results: 33,166 participants were enrolled. At hospitalization, 6,572 (19.8 %) subjects were classified as known DM, and another 2,634 (7.9 %) subjects were classified as newly diagnosed DM. In-hospital mortality was highest in newly diagnosed DM (HR 1.89, 95% CI 1.58-2.26, p < 0.001) followed by known DM (HR 1.41, 95% CI 1.18-1.69, p < 0.001) compared to non-DM. Length of hospital stay was significantly longer in newly diagnosed DM (median [IQR] 9.0 [5.0-18.0],days) than known DM (median [IQR] 5.0 [3.0-10.0],days)(p < 0.001) and non-DM (median [IQR] 4.0 [2.0-7.0],days). After adjusting for multiple covariates, newly diagnosed diabetes was independently associated with increased in-hospital mortality (p < 0.001).

Conclusions: Diabetes status at admission was closely linked to hospitalization-related outcomes. Notably, individuals with newly diagnosed diabetes demonstrated a higher risk of in-hospital mortality and a prolonged length of hospital stay.