Figure 1 Prevalence among 28 patients diagnosed with idiopathic normal‐pressure hydrocephalus of concomitantly fulfilled clinical criteria for cerebrovascular disease (CVD) or Alzheimer's disease (AD) according to the National Institute of Neurological and Communicative Disorders and Stroke and the Alzheimer's Disease and Related Disorders Association criteria. Eight patients fulfilled criteria for both CVD and AD. One patient was lost to follow‐up. The patients are subgrouped according to improvement after shunt operation (n = 9), no clinical change (n = 10) and clinical deterioration (n = 8).