Prevalence of idiopathic normal pressure hydrocephalus in older adult population in Shanghai, China: A population-based observational study.

INTRODUCTION

Idiopathic normal pressure hydrocephalus (iNPH), a condition that primarily affects the elderly, has an unclear prevalence rate in China.

METHODS

A cross-sectional survey involving 1491 seniors aged 60 and above in Shanghai was conducted. Clinical symptoms and brain imaging data were collected for the diagnosis of suboptimal probable iNPH (s-probable iNPH). The crude prevalence was calculated and the estimated prevalence was inferred.

RESULTS

The crude prevalence of s-probable iNPH was 3.09% and 2.62% respectively, using DESH score ≥6 and Radscale score ≥7 as the primary imaging diagnostic criteria. The estimated prevalence of Shanghai was 2.59% among people over 60 years old and it rose to 7.99% among people aged over 90, and it was estimated that 134,152 and 11,708, respectively, had s-probable iNPH among the corresponding age group.

DISCUSSION: The prevalence of s-probable iNPH fluctuates based on the radiological scoring systems and the defined thresholds employed, and it tends to rise with advancing age.

HIGHLIGHTS: **Significant Prevalence**: The study identified a substantial prevalence of iNPH in older adults, with rates increasing significantly with age, particularly among those aged 90-99 years and centenarians. **Diagnostic Approach**: The research utilized novel diagnostic methodologies by integrating the DESH score or Radscale score with stringent clinical symptoms, providing a closer approximation to the true prevalence of iNPH. **Gender Disparity**: A marked gender difference was observed, with the prevalence of iNPH being significantly higher in males compared to females across all age groups. **Clinical Implications**: The findings underscore the importance of considering iNPH in the differential diagnosis of dementia, particularly among older male patients presenting with cognitive impairment and gait disturbances. **Public Health Impact**: The estimated number of s-probable iNPH patients in Shanghai highlights the need for increased awareness and better management strategies for this underdiagnosed condition in the aging population.