65 Insulin-treated diabetes patients (type 1, type 2, type 3c), hospitalized in the University Hospital Halle (Saale) between 1.6.2017 and 31.12.2019 were screened and enrolled for participation in this observational cohort study based on the inclusion and exclusion criteria. The number of recruited study participants was limited by in- and exclusion criteria and by the scheduled time frame of study, a power calculation for study size was not possible. All patients provided written informed consent. Staff physicians treating the patients were unaware whether or not patients participated in this study. In addition, staff physicians did not participate in this study in any way. Thus all decisions made in study patients reflected the staff physician`s opinion and were not influenced by the organizers or by persons conducting this observational study. The ethics committee of the Medical Faculty of the Martin-Luther University Halle-Wittenberg approved this study protocol (Study number 2017-28). Data acquisition was performed according to the principles of the Declaration of Helsinki and Good Clinical Practice (E6, revision 2) from 2015.
Inclusion criteria
- Insulin-treated diabetes patients (type 1, type 2 or Type 3c Diabetes mellitus), diagnosed for at least one year before study enrollment,
- age: 18 - 99 years
- male or female
Cohort specific inclusion criteria:
- Group 1: hypertensive crisis at admission (systolic blood pressure > 180 mmHg)
- Group 2: absence of hypertensive crisis or symptomatic hypoglycemia at admission.
- Group 3: symptomatic hypoglycemia at admission
Exclusion criteria
- age below 18 years or more than 99 years
- an active tumour disease or curative care within 5 years,
- gravidity or women with child-bearing potential with no safe forms of contraception,
- severe pain (visual analogue scale from 1-10: >3),
- known secondary cause o arterial hypertension,
- septicaemia,
- allergies to adhesives, inability to use FGM
- current use of glucocorticoids,
- psychiatric disorders and all forms of dementia with lack of ability to provide an informed consent, - stage-5 chronic kidney disease (defined by estimated GFR < 15ml/min)
- acute kidney injury (AKI) with need for renal-replacement therapy
- acute or chronic heart failure (New York Heart Association class higher than 2).
Study Visits
Visit 1: Within 24 hours after admission for study recruitment and group allocation. Medical history was taken, clinical examination was carried out. Patients received instructional materials and behavioral counseling regarding diabetes care, a FGM sensor (FreeStyle libre, Abbott Diabetes Care, Abbott GmbH, Wiesbaden, Germany). A 24-hour ABPM and Holter electrocardiogram were placed.
Visit 2: Within 48 hours after admission, venous blood glucose, plasma catecholamines, serum cortisol, and routine laboratory parameters including serum creatinine and HbA1c were determined.
Visit 3: Prior to discharge or 14 days after Visit 2 (whatever applied first), the FGM sensor was removed, data were retrieved and analyzed. Concomitant medication including daily cumulative insulin dose and laboratory parameters including serum creatinine, estimated glomerular filtration rate (eGFR), if applicable, were recorded. In case of an evolving AKI as shown by an increase (>0.3 mg/dL) of serum creatinine by discharge, eGFR was not calculated. In case of an AKI prior to hospitalization as shown by a decrease (>0.3 mg/dL) of serum creatinine by discharge or in case of no change (>0.3 mg/dL) of serum creatinine by discharge, eGFR at discharge was provided.
Analysis
If applicable, both the hypertensive crisis and symptomatic hypoglycemia events at admission were used for cohort allocation and were not considered as an event for analysis. In addition, information on missing data was provided in the Tables. Continuous data were given as mean ± standard deviation. To test for normality, Kolmogorov-Smirnov test was used. For group-wise comparisons, an ordinary one-way Analysis of Variance test was used as a parametric test, Kruskal-Wallis test was used, if data showed no Gaussian distribution. As post-hoc tests, Tukey or Dunn`s test were used, where appropriate.
Primary Outcome parameters:
Number of post-admission hypoglycemic episodes (tissue glucose level < 3.9 mmol/L) per 24h of FGM
Secondary Outcome parameters:
- Change in concomitant classes and defined daily dose (DDD) of antihypertensive medications, by discharge,
- Change in daily cumulative insulin dose by discharge
- Comparison of plasma catecholamines, heart rate variability (the standard deviation of RR intervals derived from Holter electrocardiogram), HbA1c among groups