Objective: COVID-19 in people with diabetes is associated with a disproportionately worse prognosis. DKA is an acute complication of diabetes with a mortality rate of approximately 0.67%. Little is known about the natural history of DKA in the presence of COVID-19. This study aimed to explore the effects of COVID-19 on presentation, clinical course and outcome in patients presenting with DKA. Design: Retrospective cohort study. Methods: All patients treated for DKA between 1 March 2020 and 30 May 2020 were included. Patients were categorised as COVID-positive or COVID-negative based on swab test. A pre-COVID group was established using data from 01 March 2019 to 30 May 2019 as external control. Data regarding demographics, diabetes type, pH, bicarbonate, lactate, glucose, DKA duration, complications and outcome were collected. Results: A total of 88 DKA episodes were included in this study. There was no significant difference in the severity or duration of DKA between the three groups. COVID-positive T1DM were more hyperglycaemic on admission compared to COVID-negative and pre-COVID patients. There was an over representation of T2DM in COVID-positive patients with DKA than in pre-COVID or COVID-negative groups. Conclusion: COVID-19 appears to influence the natural history of DKA differently in T1DM and T2DM. Patients with T1DM and COVID-19 presented with more hyperglycaemia (60mmol/l (35.9-60.0) vs. 31.4mmol/l (28.0-39.1) vs. 24mmol/l (20.2-33.75), respectively). Patients with T2DM were unusually presenting in DKA when infected with COVID-19 with greater ICU need and higher mortality rates. A collaborative, multi-centre study is needed to provide more definitive results.

Since elderly people are prone to develop both hypo- and hyper-natraemia, we have investigated the biochemical and hormonal responses to overnight (9 h) abstinence from fluids and subsequent oral water load (20 ml/kg) in a group of healthy elderly (E) (mean age 68 years) and young (Y) (mean age 28 years) volunteers. The elderly subjects had significantly higher baseline plasma osmolality (E 293.5 +/- 0.5, Y 290.5 +/- 0.8 mOsm/kg, p < 0.05) but lower urinary osmolality (E 508 +/- 47, Y 842 +/- 52 mOsm/kg, p < 0.001) and lower plasma vasopressin (E 0.5 +/- 0.1, Y 2.3 +/- 0.6 pmol/l, p < 0.001) than the young. There was a significant difference in the mode of excretion, particularly maximum free water clearance (E 6.0 +/- 0.6, Y 10.1 +/- 0.8 ml/min) but no difference in the overall ability to excrete the water load (at 4 h E 93 +/- 8%, Y 92 +/- 5%, p > 0.05). The biochemical and hormonal results suggest that the elderly subjects were in a state similar to partial cranial diabetes insipidus which may predispose them to dehydration and hypernatraemia. The reduction in maximum free water clearance may predispose them to hyponatraemia if excess fluid is administered.

This study confirms that suckling is a potent stimulus to thirst in the mother, and is not associated with vasopressin release or dependent on any measurable alterations in osmoregulation. What actually stimulates thirst during breast feeding remains unknown, but there are two potential explanations for these observations: (1) suckling sends nerve impulses to the paraventricular and supraoptic nuclei in the hypothalamus which may have afferents within the central nervous system which stimulates a thirst response simultaneous with oxytocin release; (ii) a learned anticipation of thirst may be occurring in a situation associated with expectant fluid loss to preserve homeostasis.

No abstract

No abstract