can mean different things to different people.Some people use the term for vertigo or spinning sensation, some use it for the feeling of near fainting (presyncope
) or syncope, some use it for unsteadiness while trying to walk etc.
To ascertain the exact cause of dizziness a detailed history is of paramount importance. Investigations can only contribute in this regard but cannot confirm the cause.
Like you suspect a Postural Hypotension
needs to be ruled out. Blood pressure needs to be measured while lying down and while standing. Its also important to know if she has any associated symptoms like blurring of vision, slurring of speech or diplopia
(seeing objects as two ) or unsteadiness on walking when she feels giddy. If these symptoms are present it could suggest a Vertebrobasilar TIA (Transient Ischemic Attack
Other possibilities that needs consideration include a Peripheral Vestibular problem which could be manifesting as giddiness.Its important to enquire about any hearing deficits or sensation of ringing in the ear.
In the elderly giddiness could be due to multiple causes rather than a single cause, like a Neuropathy, musculoskeletal problem, Parkinsonism or visual impairment
Cardiac causes like abnormal heart rhythms needs exclusion. Another cause of giddiness is psychogenic or more commonly seen in anxious or depressed people.
Among the many reasons mentioned...A Neurologist
should be able to help in determining the exact cause. Hope this helps as an overview !