Association between left-handedness and gastrointestinal symptoms

Several studies have shown associations between left-handedness and several chronic diseases such as bronchial asthma and inflammatory bowel disease. Perceptual responses within the brain-gut axis play a crucial role in the development of the cardinal symptoms of functional gastrointestinal (GI) diseases, including dyspepsia and irritable bowel syndrome (IBS). The aim of this study was to determine the association between left-handedness and GI symptoms or diseases.

2,447 Japanese who underwent a routine health check-up were asked to complete a self-report questionnaire regarding age, gender, writing handedness and GI symptoms experienced over the past 3 months, including heartburn, acid regurgitation, epigastric pain, postprandial fullness, abdominal pain/discomfort, nausea and/or chest pain. Symptoms were positive when their frequency was 2 to 3 days per month or more. Diagnosis of dyspepsia and IBS was performed according to the Rome III Integrative Questionnaire.

Left-handedness was observed in 177 (7.2%) subjects. Early satiation, abdominal pain/fullness and postprandial fullness were less commonly observed in left-handed individuals. After adjustment for age and sex, left-handedness was found to be significantly associated with decreased OR for early satiation (OR = 0.43; 95% CI: 0.23-0.78). There were no significant associations between left-handedness and GERD (gastroesophageal reflux disease), dyspepsia or IBS.

This study demonstrated a significant negative association between left-handedness and early satiation. The findings suggest that cerebral lateralization may affect the development of GI symptoms.