This information was copied from the below website. It is also another condition worth mentioning.
The symptoms of NORMAL PRESSURE HYDROCEPHALUS may mimic those of Alzheimer's, Parkinson's Disease, and other types of Dementia, making NPH more difficult to diagnose. Although Alzheimer's patients may eventually develop gait disturbance and incontinence, with Normal Pressure Hydrocephalus, gait disturbance tends to present first, then incontinence, and last, dementia. With Alzheimer's Disease, confusion and dementia are the first symptoms to appear, with other symptoms developing later in the progression of the disease. Similar symptoms may appear in Small Vessel Disease, Alzheimer's Disease, Parkinson's Disease, Dementia With Lewy Bodies, or a number of other neurological conditions. Dementia and weakness in the arms and legs may also be caused by medication, vitamin deficiency (such as B12), or chemical imbalance.
Primarily NPH is seen in adults over 55 (the median age is said to be mid-70's), and they may have a variety of symptoms caused by more than one medical condition or disease. Any of the symptoms below may be caused by other medical and neurological conditions and may not indicate NPH, OR, a patient may have more than one neurological disorder. Normal Pressure Hydrocephalus is estimated to represent 5%-10% of all cases of dementia.
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