Extent of tissue damage .
Severity of the initial neurological deficit .
Lesion type and size, where focal lesions have better prospects of recovery [4,19].
Location of lesion. Cortical lesions have a better tendency to recover as opposed to subcortical lesions. Lesions of the dominant hemisphere herald a poorer prognosis than non-dominant hemisphere lesions, as do lesions of sensitive areas in medulla and mid-brain .
Complications such as raised intracranial pressure, metabolic problems, inter-current infection and uncontrolled epilepsy .
Co-existing diseases .
Pre-existing mood disorders and psychiatric illness .
Racial factors have been suggested following a country-wide survey of stroke patients in the USA. Comparable strokes in blacks were more severe and less likely to recover than in white populations .
Genetic factors have been incriminated in relation to different alleles of apolipoprotein E in genes E2, E3 and E4, linked to amyloid deposition in cortex which heralds a tenfold increase in mortality as compared to those who are non-predisposed .
Nutritional status .
Alcoholism and substance misuse .
Pharmaceutical preparations. Experimental evidence suggests that clonidine, haloperi- dol, prazosin, GABA, diazepam, phenytoin and phenobarbitone have an adverse inﬂu- ence on the process of recovery . Preparations that may promote recovery are still experimental and the likely prepa- rations are norepinephrine, amphetamine and nerve growth factors . Investigations in human subjects where ampheta- mine was used for treatment following head injury or stroke are of small scale, with variable results , but a beneficial effect has been suggested in double-blind studies . Bromocriptine was found to enhance ﬂuency in aphasics  but GM1 ganglioside studied in humans revealed no convincing evidence of benefit .
Pre-injury education and intelligence.
Those with higher pre-morbid IQ and higher levels of education have better prospects of improvement .
Appropriate attention by carers and partners and other social factors such as support by friends and family .
Forced use of target organs such as limbs and speech is known to promote recovery  and emphasizes the place of physio- therapy and rehabilitation.
These factors are important in selecting patients for rehabilitation and planning programs to suit each individual. Elderly patients, those with overwhelming general medical problems, poor nutritional state, poor pre-morbid intelligence and pre-existing psychiatric disorders herald a poor prognosis and such patients may need to be excluded from a general rehabilitation program or managed in special placements.
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