some of the common medical complications are congenital heart defects, hearing loss, cataracts, dislocations, leukaemia, chronic constipation, sleep apnea (interrupted breathing during sleep) and dementia. Dementia is usually referred to as the inability to memorise, recognise, make decisions or make judgments that interfere with normal routine work. The most frequent form of dementia is Alzheimer's disease and the low data holding capacity syndrome.