Endocrine Abstracts

Sodium-glucose co-transporter-2 inhibitors (SGLT2i) are used therapeutically in type 2 diabetes (T2DM), cardiovascular and renal disease. SGLT2i reduce the risk of cardiovascular events, kidney disease progression and hospitalisation for heart failure. A transient osmotic diuresis is expected on initiation. The safety of initiating SGLT2i in patients with arginine-vasopressin deficiency (AVP-D) remains unexplored. Few case reports have cautioned against its use due to risk of hypernatraemia and dehydration. We report a case series of eight patients with AVP-D initiated on SGLT2i under close supervision and their medium-term outcome. All patients (M:F,1:1) were established on desmopressin therapy (DDAVP) for AVP-D due to sellar(n = 3), suprasellar(n = 3) or intracranial(n = 2) tumours. Indications for SGLT2i therapy were: T2DM(n = 7) and heart failure(n = 1). On initiation with oral dapagliflozin 10mg daily, patients monitored their daily weights for a week and reported any osmotic symptom or dehydration (>5% weight loss). Serum biochemistry was checked before and a week after initiation. Data is expressed as median(range). There was no change in weight, serum sodium and urea after a week: 93(72-108) vs. 93(72-110)kg, 138(126-143) vs. 138(132-145)mmol/l and 4.7(2.1-10.7) vs. 4.7(2.6-8.6)mmol/l, respectively. One patient with adipsic AVP-D required an increase in obligate daily fluid intake from 1L to 1.2L due to acute weight loss. 3/8 patients experienced polyuria. Two were managed with uptitration of DDAVP. One patient chose to stop SGLT2i due to developing concurrent vaginal thrush. For the seven patients who were stabilised on SGLT2i there was no incidence of electrolyte imbalance, diabetic ketoacidosis or hospital admission due to osmotic decompensation over a median 13(6-36) months. HbA1c, serum sodium and creatinine remained stable during follow-up. Our data supports the use of SGLT2i in patients with AVP-D under close supervision on initiation. Medium-term data is reassuring.