Abstract Background Gastro-oesophageal reflux disease (GORD) can present with typical symptoms or atypical or laryngopharyngeal reflux (LPR) symptoms. The role of impaired oesophageal motility in these two clinically distinct groups has not been previously examined. Methods This study is a retrospective analysis of 361 consecutive patient records that was extracted from a prospectively populated research database. Patients were categorised by symptom profile as predominantly LPR or GORD (98 GOR and 263 LPR). Presenting symptom profile, pH studies, oesophageal manometry and scintigraphy and the relationship between the above were analysed. Results Severe oesophageal dysmotility was more prevalent in LPR group (P = 0.037). Severe oesophageal dysmotility was strongly associated with isotope aspiration in both groups (P = 0.001). 24 per cent of patients showed evidence of pulmonary aspiration on scintigraphy. Significant correlation was established between total proximal acid on 24-hour pH monitoring and isotope aspiration in both groups (P = 0.00). Rising pharyngeal curves on scintigraphy were the strongest predictors of isotope aspiration (P = 0.00). Conclusion Early research on oesophageal dysmotility has suggested reduced oesophageal clearance in individuals with IOM. This selected group of patients showed a high degree of impaired oesophageal motility, which was associated with rising time-activity curves in both the upper oesophagus and pharynx. The presence of refluxate in the upper oesophagus can stimulate cough via ‘reflex’ afferent pathways and the presence of gastric contents in the pharynx can cause direct irritation to upper airways, both resulting in cough. Reduced pressures in the lower oesophageal sphincter were equally prevalent in LPR and GORD groups and therefore were not discriminatory between the clinical groups. The impairment of oesophageal clearance secondary to diminished oesophageal motility, may offer a plausible explanation for the development of symptoms via combined ‘reflux’ and ‘reflex’ pathways, allowing continued oesophageal exposure or proximal exposure to refluxate. The ROC and cluster analysis demonstrated strong predictive values and linkages between ineffective oesophageal motility and rising pharyngeal time-activity curves for the prediction of lung aspiration. This may form the basis of a new approach to the definitive diagnosis of LPR and lung aspiration. Oesophageal dysmotility is a key factor in pathophysiology of LPR. Severe impaired oesophageal motility is strongly associated with pulmonary aspiration in both LPR and GORD. Disclosure All authors have declared no conflicts of interest.