Sympathetic Activity in Patients with Type 2 Diabetes Mellitus Treated with Empagliflozin or Hydrochlorothiazide

Changes in sympathetic nervous system activity may contribute to beneficial effects of sodium glucose transporter (SGLT2) inhibition on cardiovascular outcomes. We hypothesized that SGLT inhibition with empagliflozin lowers sympathetic activity compared with hydrochlorothiazide (HCT) to discern SGLT2-specific actions from non-specific responses to increased natriuresis. In this double-blind, randomized study patients with type 2 diabetes mellitus on metformin monotherapy received either 25 mg/day empagliflozin (n=20) or 25 mg/day HCT (n=21) for 6 weeks. Muscle sympathetic nerve activity (MSNA) , blood pressure, cardiovascular, and metabolic biomarkers were assessed at baseline and end of treatment. Empagliflozin significantly increased urinary glucose excretion (difference in change from baseline 47.4 mmol/l vs. HCT) , reduced fasting plasma glucose (-1.91 mmol/l) , HbA1c (-0.58%) , and body weight (-1.23 kg, all p<0.05) . Office systolic blood pressure decreased with both treatments. MSNA (burst frequency -1.95 [95% confidence interval -8.67; 4.78] bursts/min) , baroreflex heart rate control (0.84 [-1.18; 2.87] ms/mmHg) and plasma catecholamines did not change significantly with either treatment. MSNA increased with higher body weight loss with both treatments, but more pronounced and significant only with HCT (p=0.0015) . In conclusion, neither empagliflozin nor HCT treatment led to clinically relevant changes in sympathetic activity. Given the important role of the sympathetic nervous system in the progression of cardiovascular disease, mechanisms attenuating sympathetic activity in the face of increased sodium excretion deserve further attention. Disclosure K.Heusser: None. J.Tank: None. A.Fischer: None. T.Heise: Advisory Panel; Novo Nordisk A/S, Research Support; ADOCIA, AstraZeneca, Biocon, Boehringer Ingelheim International GmbH, Crinetics Pharmaceuticals, Inc., Eli Lilly and Company, Gan & Lee Pharmaceuticals, Genova, Nestlé, Neuraly Inc., Novo Nordisk A/S, Sanofi, Zealand Pharma A/S, Speaker's Bureau; Eli Lilly and Company, Gan & Lee Pharmaceuticals, Novo Nordisk A/S. J.Jordan: Consultant; Novo Nordisk, Other Relationship; Eternygen, Research Support; Boehringer Ingelheim International GmbH.