To describe subjective presenting motor and non-motor symptoms in individuals with probable and definite idiopathic normal pressure hydrocephalus (iNPH).

Idiopathic normal pressure hydrocephalus (iNPH) is commonly identified with the clinical triad of gait dysfunction, memory impairment, and urinary incontinence. Moreover, non-motor symptoms such as anxiety, depression, and apathy have been described in this population. While the motor aspects of NPH have been likened to Parkinson's disease and other parkinsonian disorders, the extent of overlap in non-motor manifestations has not been well described.

This is a retrospective study describing patient reported motor and non-motor symptoms of probable and definite iNPH according to the Japanese guidelines seen at the University of Connecticut NPH clinic between January 2020 to June 2023.

Out of the 135 patients in the NPH clinic, 54 (40%) patients met the inclusion criteria. Thirty-one (57%) were male, with a mean age of 77 years + 7, and a mean duration of symptoms attributed to NPH of 3.9 years + 2.92. The most frequently reported motor symptoms after gait dysfunction (98%) included generalized slowness (46%), handwriting changes (46%), tremor (43%), hypophonia (37%), and trouble turning in bed (37%). Among nonmotor symptoms, occurring after cognitive changes (85%) and urinary dysfunction (78%), patients reported sleep disturbances (63%), depression (56%), anxiety (54%), fatigue (50%), and constipation (46%). Interestingly 30% reported symptoms suggestive of REM behavioral sleep disorder (RBD) and 24% reported hyposmia. Orthostatic symptoms were observed in 39% of patients.

Our study contributes to an expanded understanding of patient-reported motor and nonmotor symptoms of probable and definite iNPH. Notably, our study reveals an overlap between nonmotor symptoms in NPH and those observed in synucleopathies, with presence of RBD and hyposmia. Further studies are needed to better understand the spectrum of nonmotor symptoms in this population and their impact on quality of life.