TY - JOUR

T1 - Transcutaneous vagal nerve stimulation for treating gastrointestinal symptoms in individuals with diabetes

T2 - a randomised, double-blind, sham-controlled, multicentre trial

AU - Kornum, Ditte S.

AU - Bertoli, Davide

AU - Kufaishi, Huda

AU - Wegeberg, Anne-Marie

AU - Okdahl, Tina

AU - Mark, Esben B.

AU - Høyer, Katrine L.

AU - Frøkjær, Jens B.

AU - Brock, Birgitte

AU - Krogh, Klaus

AU - Hansen, Christian S.

AU - Knop, Filip K.

AU - Brock, Christina

AU - Drewes, Asbjørn M.

N1 - Publisher Copyright: © The Author(s) 2024.

PY - 2024

Y1 - 2024

N2 - Aims/hypothesis: Diabetic gastroenteropathy frequently causes debilitating gastrointestinal symptoms. Previous uncontrolled studies have shown that transcutaneous vagal nerve stimulation (tVNS) may improve gastrointestinal symptoms. To investigate the effect of cervical tVNS in individuals with diabetes suffering from autonomic neuropathy and gastrointestinal symptoms, we conducted a randomised, sham-controlled, double-blind (participants and investigators were blinded to the allocated treatment) study. Methods: This study included adults (aged 20–86) with type 1 or 2 diabetes, gastrointestinal symptoms and autonomic neuropathy recruited from three Steno Diabetes Centres in Denmark. Participants were randomly allocated 1:1 to receive active or sham stimulation. Active cervical tVNS or sham stimulation was self-administered over two successive study periods: 1 week of four daily stimulations and 8 weeks of two daily stimulations. The primary outcome measures were gastrointestinal symptom changes as measured using the gastroparesis cardinal symptom index (GCSI) and the gastrointestinal symptom rating scale (GSRS). Secondary outcomes included gastrointestinal transit times and cardiovascular autonomic function. Results: Sixty-eight participants were randomised to the active group, while 77 were randomised to the sham group. Sixty-three in the active and 68 in the sham group remained for analysis in study period 1, while 62 in each group were analysed in study period 2. In study period 1, active and sham tVNS resulted in similar symptom reductions (GCSI: −0.26 ± 0.64 vs −0.17 ± 0.62, p=0.44; GSRS: −0.35 ± 0.62 vs −0.32 ± 0.59, p=0.77; mean ± SD). In study period 2, active stimulation also caused a mean symptom decrease that was comparable to that observed after sham stimulation (GCSI: −0.47 ± 0.78 vs −0.33 ± 0.75, p=0.34; GSRS: −0.46 ± 0.90 vs −0.35 ± 0.79, p=0.50). Gastric emptying time was increased in the active group compared with sham (23 min vs −19 min, p=0.04). Segmental intestinal transit times and cardiovascular autonomic measurements did not differ between treatment groups (all p>0.05). The tVNS was well-tolerated. Conclusions/interpretation: Cervical tVNS, compared with sham stimulation, does not improve gastrointestinal symptoms among individuals with diabetes and autonomic neuropathy. Trial registration: ClinicalTrials.gov NCT04143269 Funding: The study was funded by the Novo Nordisk Foundation (grant number NNF180C0052045) Graphical Abstract: (Figure presented.)

AB - Aims/hypothesis: Diabetic gastroenteropathy frequently causes debilitating gastrointestinal symptoms. Previous uncontrolled studies have shown that transcutaneous vagal nerve stimulation (tVNS) may improve gastrointestinal symptoms. To investigate the effect of cervical tVNS in individuals with diabetes suffering from autonomic neuropathy and gastrointestinal symptoms, we conducted a randomised, sham-controlled, double-blind (participants and investigators were blinded to the allocated treatment) study. Methods: This study included adults (aged 20–86) with type 1 or 2 diabetes, gastrointestinal symptoms and autonomic neuropathy recruited from three Steno Diabetes Centres in Denmark. Participants were randomly allocated 1:1 to receive active or sham stimulation. Active cervical tVNS or sham stimulation was self-administered over two successive study periods: 1 week of four daily stimulations and 8 weeks of two daily stimulations. The primary outcome measures were gastrointestinal symptom changes as measured using the gastroparesis cardinal symptom index (GCSI) and the gastrointestinal symptom rating scale (GSRS). Secondary outcomes included gastrointestinal transit times and cardiovascular autonomic function. Results: Sixty-eight participants were randomised to the active group, while 77 were randomised to the sham group. Sixty-three in the active and 68 in the sham group remained for analysis in study period 1, while 62 in each group were analysed in study period 2. In study period 1, active and sham tVNS resulted in similar symptom reductions (GCSI: −0.26 ± 0.64 vs −0.17 ± 0.62, p=0.44; GSRS: −0.35 ± 0.62 vs −0.32 ± 0.59, p=0.77; mean ± SD). In study period 2, active stimulation also caused a mean symptom decrease that was comparable to that observed after sham stimulation (GCSI: −0.47 ± 0.78 vs −0.33 ± 0.75, p=0.34; GSRS: −0.46 ± 0.90 vs −0.35 ± 0.79, p=0.50). Gastric emptying time was increased in the active group compared with sham (23 min vs −19 min, p=0.04). Segmental intestinal transit times and cardiovascular autonomic measurements did not differ between treatment groups (all p>0.05). The tVNS was well-tolerated. Conclusions/interpretation: Cervical tVNS, compared with sham stimulation, does not improve gastrointestinal symptoms among individuals with diabetes and autonomic neuropathy. Trial registration: ClinicalTrials.gov NCT04143269 Funding: The study was funded by the Novo Nordisk Foundation (grant number NNF180C0052045) Graphical Abstract: (Figure presented.)

KW - Autonomic neuropathy

KW - Diabetic gastroenteropathy

KW - Gastrointestinal dysmotility

KW - Gastrointestinal symptoms

KW - Gastroparesis

KW - Heart rate variability

KW - Vagal nerve stimulation

U2 - 10.1007/s00125-024-06129-0

DO - 10.1007/s00125-024-06129-0

M3 - Journal article

C2 - 38546822

AN - SCOPUS:85188918779

VL - 67

SP - 1122

EP - 1137

JO - Diabetologia

JF - Diabetologia

SN - 0012-186X

IS - 6

ER -