Department of Gastroenterology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, China.
Am J Gastroenterol. 2013 Sep;108(9):1516-25. doi: 10.1038/ajg.2013.198. Epub 2013 Aug 6.
Bloating and distention are often attributed to dietary factors by patients with irritable bowel syndrome (IBS). This study examined the effects of gas production and visceral hypersensitivity on digestive symptoms after lactose ingestion in a population with lactase deficiency.
IBS patients (n=277) and healthy controls (HCs, n=64) underwent a 20-g lactose hydrogen breath test (LHBT) with evaluation of hydrogen gas production and lactose intolerance (LI) symptoms. Abdominal distention (199 IBS, 40 HCs) was measured during LHBT. Rectal sensitivity (74 IBS, 64 HCs) was assessed by barostat studies.
Hydrogen production and distention were similar in IBS patients and HCs during LHBT; however, LI was more frequent in IBS (53.8 vs. 28.1%, P<0.001), especially bloating (39.0% vs. 14.1%, P<0.001) and borborygmi (39.0 vs. 21.9%, P=0.010). Only 59.0% of patients with bloating had distention. No correlation was observed between girth increment and bloating (P=0.585). IBS patients had lower rectal sensory thresholds (P=0.001). Multivariate analysis indicated that hydrogen production increased bloating (odds ratio (OR) 2.19, 95% confidence interval (CI) 1.09-4.39, P=0.028) and borborygmi (OR 12.37, 95% CI 3.34-45.83, P<0.001) but not distention (P=0.673). Visceral hypersensitivity was associated with bloating (OR 6.61, 95% CI 1.75-25.00, P=0.005) and total symptom score (OR 3.78, 95% CI 1.30-10.99, P=0.014).
Gas production and visceral hypersensitivity both contribute to digestive symptoms, especially bloating and borborygmi, in IBS patients after lactose ingestion. Objective abdominal distention is not correlated with subjective bloating.
肠易激综合征（IBS）患者常将腹胀归咎于饮食因素。本研究旨在研究乳糖不耐受（LI）人群中，产气量和内脏高敏性对乳糖摄入后消化症状的影响。
IBS 患者（n=277）和健康对照者（HC，n=64）进行 20g 乳糖氢呼气试验（LHBT），评估氢气生成和乳糖不耐受（LI）症状。LHBT 期间测量腹胀（199 例 IBS，40 例 HC）。通过测压法研究评估直肠敏感性（74 例 IBS，64 例 HC）。
LHBT 期间，IBS 患者和 HC 之间的氢气生成和腹胀相似；然而，IBS 患者中 LI 更为常见（53.8%比 28.1%，P<0.001），尤其是腹胀（39.0%比 14.1%，P<0.001）和肠鸣（39.0%比 21.9%，P=0.010）。仅有 59.0%的腹胀患者有腹胀。腹围增加与腹胀无相关性（P=0.585）。IBS 患者直肠感觉阈值较低（P=0.001）。多变量分析表明，氢气生成增加腹胀（比值比（OR）2.19，95%置信区间（CI）1.09-4.39，P=0.028）和肠鸣（OR 12.37，95% CI 3.34-45.83，P<0.001），但不增加腹胀（P=0.673）。内脏高敏性与腹胀（OR 6.61，95% CI 1.75-25.00，P=0.005）和总症状评分（OR 3.78，95% CI 1.30-10.99，P=0.014）相关。
乳糖摄入后，产气和内脏高敏性均导致 IBS 患者出现消化症状，尤其是腹胀和肠鸣。客观腹胀与主观腹胀无相关性。
