Levothyroxine therapy and impaired clearance are the strongest contributors to small intestinal bacterial overgrowth: Results of a retrospective cohort study

Table 2 Hypo-/achlorhydria

	SIBO		Non-SIBO		χ2 test	OR	RR
	n = 175	%	n = 1634	%	P value
Gastrectomy	4	2.3	11	0.7	0.0491	3.451	0.295
Atrophic gastritis	2	1.1	5	0.3	0.141	-	-
PPI therapy	70	40.0	519	31.8	0.0341	1.432	0.794
Ulcer indicated PPI therapy	5	2.9	47	2.9	0.611	-	-
Gastritis indicated PPI therapy	20	11.4	195	11.9	0.481	-	-
GERD indicated PPI therapy	20	11.4	179	11.0	0.464	-	-
Indicated PPI therapy	42	24.0	395	24.2	0.522	-	-
Not indicated PPI therapy	58	33.1	370	22.6	0.0021	1.728	0.693

¹Statistically significant with P < 0.05 in χ² test. Patients with SIBO had a history of gastrectomy more often and were more likely to take PPI. In subgroup analysis, those patients who received PPI due to peptic ulcer disease, gastritis or GERD had the same risk of developing SIBO, while those patients who did not exhibit such indications had a 1.7-fold increased risk of showing SIBO. SIBO: Small intestinal bacterial overgrowth; PPI: Proton pump inhibitor; GERD: Gastroesophageal reflux disease.