Hiccups in Parkinson's disease: an overlooked non-motor symptom?

Although hiccups may be a non-motor symptom of Parkinson's disease (PD), they have attracted little research attention to date.

To investigate the frequency of occurrence of hiccups in PD.

The presence of hiccups was evaluated using face-to-face interviews in 90 PD patients and 100 age-matched controls.

Eighteen (20%) of the PD patients and three (3%) of the control subjects reported frequent hiccups. The reported occurrence of hiccups was significantly higher in PD patients than controls. Nine patients noted that hiccups had appeared in the past, particularly around the onset of PD. One patient was admitted to our hospital because of intractable hiccups before a diagnosis of PD was made. Another eight patients reported the emergence of hiccups following the administration of antiparkinsonian drugs.

Our results suggest that hiccups are more frequent in PD patients than healthy controls. Further studies are required to determine whether hiccups are associated with intrinsic pathology, to dopamine replacement therapy, or both.