Narcolepsy and odor: preliminary report

This study has been carried out to test the clinical hypothesis of personal smell as a hint to the diagnosis of narcoleptic patients.

Sweat samples from narcoleptic and healthy controls were tested independently by two trained dogs and their positive or negative detection compared to the gold standard diagnosis for narcolepsy. Neither trainer nor dog knew the source of the sample selected or its placement in the search device. Twelve narcoleptic patients, both sexes and various ages, recruited from April 2011 to June 2012 and diagnosed according to standard criteria, through their clinical records and nocturnal polysomnography plus multiple sleep latency test, made up the patient group. The control group was made up of 22 healthy volunteer without sleep disorders, both sexes and various ages. Sweat samples from both patients and controls were collected following the same protocol to avoid contamination, and tested independently by two trained dogs.

Eleven narcoleptic were detected positive by the dogs while only three controls.

It seems that narcoleptic patients have a distinct typical odor that trained dogs can detect. The development of olfactory test could be a useful method in the screening of narcolepsy while opens a new research area.