Effect of cigarette smoking on gastric emptying of solids in Japanese smokers: a crossover study using the 13C-octanoic acid breath test.
BACKGROUND
Cigarette smoking is associated with an increased risk of peptic ulcer and gastroesophageal reflux disease. Gastric emptying disorders may play a role in the development of these upper gastrointestinal diseases. Thus, studies examining a link between smoking and gastric emptying disorders have clinical relevance. This study was conducted to investigate the effect of smoking on gastric emptying of solids in Japanese smokers.


METHODS
The (13)C-octanoic acid breath test was performed in eight male habitual smokers on two randomized occasions (either sham smoking or actively smoking). The time vs (13)CO(2) excretion rate curve was mathematically fitted to a conventional formula of y (t) = m*k*beta*e(-k*t)*(1 - e(-k*t))(beta-1), and the parameters of k and beta were determined: under the crossover protocol, a larger (smaller) beta indicates slower (faster) emptying in the early phase, and a larger (smaller) k indicates faster (slower) emptying in the later phase. The half (13)CO(2) excretion time (t(1/2b) = -[ln(1 - 2(-1/beta))]/k) and the time of maximal (13)CO(2) excretion rate (t(max) = [lnbeta]/k) were also calculated. Between the two occasions, k, beta, t(1/2b), and t(max) were compared by the Wilcoxon signed-rank test.


RESULTS
After smoking, k was significantly increased. No significant differences were found in beta, t(1/2), and t(max) between the two occasions.


CONCLUSIONS
The increase in k suggests the acceleration of gastric emptying in the later phase. For the first time, this study has revealed that acute smoking speeds the gastric emptying of solids in Japanese habitual smokers.
Sanaka
Masaki
M
Department of Internal Medicine, School of Medicine, Teikyo University, 2-11-1 Kaga Itabashi-ku, Tokyo, 173-8605, Japan.
Anjiki
Hajime
H
Tsutsumi
Hiroko
H
Abe
Koichiro
K
Kawakami
Tomotaka
T
Saitoh
Masaki
M
Yamamoto
Takatsugu
T
Ishii
Tarou
T
Kuyama
Yasushi
Y
D000328:Adult; D044466:Asian People; D001944:Breath Tests / Q000379:methods; D002210:Caprylates; D002245:Carbon Dioxide / Q000032:analysis; D002247:Carbon Isotopes; D018592:Cross-Over Studies; D005500:Follow-Up Studies; D005746:Gastric Emptying / Q000502:physiology*; D005764:Gastroesophageal Reflux / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D012907:Smoking / Q000009:adverse effects* / Q000453:epidemiology; D013276:Stomach Ulcer / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology
D002210:Caprylates; D002247:Carbon Isotopes; D002245:Carbon Dioxide; C031492:octanoic acid