Aims: 

The aim of the study was to find out whether CRS is changed in children with gastro-oesophageal reflux disease (GORD) and children with Type 1 Diabetes mellitus (DM). Information from literature claim that heightened exposure of distal oesophagus to acid in adult patients causes an appreciable increase in cough reflex sensitivity. Opposite, CRS could be weakened according to the presence of autonomic neuropathy (DAN) in children with DM.

Methods: 

The CRS test was performed in 35 children suffering from Diabetes mellitus type 1 and in 20 children with symptoms suggestive of GORD. The results were compared with the group of age-matched 27 healthy children. Cough was induced by inhalation of capsaicin aerosol in doubling concentrations (0.61-1250 mmol/l) for 400 ms each. CRS was defined as the lowest capsaicin concentration that evoked 2 or more coughs (C2 parameter).

Results: 

A significant decrease (P = 0.005) of CRS was found in diabetic children with DAN [n = 12; C2: 221.0 mmol/l (95%CI: 75.7- 644.8 mmol/l)] compared with diabetic children without DAN [n = 23; C2: 42.7 mmol/l (95% CI: 23.1-79.0 mmol/l)]. CRS in the group of children with suspected GORD [C2: 17.0 mmol/l (6.4-45.6 mmol/l)] and with confirmed GORD [C2: 13.4 mmol/l (3.6-50.9 mmol/l)] were significantly elevated (P < 0.05) compared with healthy children [C2: 72.1 mmol/l (25.5 203.9 mmol/l)].

Conclusion: 

We have found that CRS is decreased in diabetic children with DAN when compared with diabetic children without DAN. The CRS changes in children suffering from GORD are similar to those described in adult patients with GORD.