Factors Affecting Potential For Recovery Of Function Following a Stroke Numerous studies have attempted to establish the prognostic indicators for functional

recovery following stroke however the factors associated with poor outcomes are far from clear. Wade et al, (1985) found that in a group of 99 patients, urinary incontinence present between 7 and 10 days post stroke was associated with poor survival (chi-square = 5.3 ; p < 0.05) and an increase in the level of disability at 3 months. There is no chi- square value for the relationship between dependence and incontinence although a p value of < 0.05 for all functions recorded is stated.

In the study of 976 patients Wade and Langton Hewer (1987) use a multiple regression analysis to establish the prognostic indicators for recovery. This is an inappropriate method of analysis as it requires at least an interval measuring scale in order to produce statistically valid results (Aitman, 1995). Of all the measures used in this study, including the Barthel Index, Motricity scores and sitting balance, only age fulfilled this requirement, therefore the results are invalid. Wade's (1985) earlier findings however, have subsequently been confirmed by Gelber et al., (1994) in their study of urinary retention during the first 24 hours following a stroke.

The results of Wade's studies also suggested that age, correctly analysed, was an important prognostic indicator of functional recovery; however, in their review of studies associating increasing age with poor outcomes Jeffery and Good (1995) suggest that this is less clear. This lack of agreement between studies may in part be due to the method of measurement of functional recovery used to identify associations between age and prognosis in this domain. It is unclear whether the functional status of the patients is achieved as a result of recovery or their ability to compensate for loss of function.

Nakayama et al., (1994) using the Barthel Index to measure levels of residual disability suggested that whilst older and younger patients had the same degree of neurological recovery, older patients demonstrated a lower level of improvement on the Barthel Index. Kaira (1994) also found that younger patients had higher Barthel Index scores than older patients in a study of 245 patients randomised to either stroke units or medical wards. As it would appear that the Barthel Index may not measure ’normality’ it is difficult to establish the clinical significance of this information .

Jeffery and Good (1995) reinforce this problem by suggesting that the reported 7% decrease in total Barthel score gain for every 10 year increase in age found by Nakayama et al., (1994) may be due to the fact that older patients have ‘less compensatory ability

than other patients. ’ This view supports the earlier presentation that the Barthel Index is

a measure of compensation rather than a measure of the patient’s recovery. Indeed further studies have presented conflicting reports of association between age and recovery, Borucki et al., (1992) also using the Barthel Index found evidence of a difference between age and total Barthel scores.

Jeffery and Good (1995) suggest that age and severity of stroke at admission may, in combination, determine functional outcomes. Reporting a study by Alexander (1994), in which admission severity and age interacted to reduce the probability of home discharge, Jeffery and Good summarise by stating the older more severely involved patients tend to benefit less from rehabilitation. This research will be discussed in the light of the findings of this study where the levels of severity were recorded at admission using the National Institute of Health Stroke Scale (Brott et al., 1989) and the Rankin handicap scale (Rankin 1957).

Wade et al., (1987) also reported that the functional ability and sitting balance were prognostic factors to recovery. Using the multiple regression analysis of Barthel scores, Motricity Index scores (Demeurisse et al., 1980), visual fields, IQ, sitting balance and cogitative function, they found that good sitting balance had the worse outcome. This is clinically highly unlikely and in contrast to previous studies (Prescott et al., 1982). It might be suggested that the inappropriate method of analysis, discussed earlier, may have contributed to Wade’s (1987) unusual findings.

Riddoch et al., (1995), in their review of prognostic indicators for functional recovery, present conflicting reports of the effect of lesion site on levels of recovery. Denes et al., (1982), in a study of unilateral spatial neglect following stroke, found that patients with right sided brain damage (RBD) took longer to become independent than patients with a left sided brain damage (LBD). Wade et al., (1984) using the Barthel Index to measure levels of disability found that patients with a LBD attended rehabilitation for longer and had better Barthel scores than RBD patients. They state that the longer stay was probably a reflection of the speech therapy requirements as apparently these patients

were not receiving physiotherapy during this period. However, in conclusion, Wade states that the side of the lesion did not affect physical outcomes even though they reported higher Barthel Scores at discharge in LBD patients. The conflict between summary and evidence in this study make it difficult to establish whether Wade et al., were agreeing or disagreeing with the findings of Denes et al.

The question of unilateral spatial neglect and functional prognosis has also received considerable attention in the literature. Denes stating that this impairment is found more frequently in RBD patients and that it ‘seems to be crucial in hampering their

performance.' On closer inspection however the sample studied was only 12 with 8 RBD

patients having unilateral neglect and 5 LBD patients not conclusive evidence of a relationship between hemispheres and the presence of neglect. Using a modified ADL scale developed by De Lagi et al., (1960) Denes states that LBD patients improved more than RBD patients, however as the ADL scale included 8 areas of motor skills, personal hygiene and feeding the final mean scores being used to obtain a t value it is impossible to establish what the actual difference between the left and right lesion sites were. The effects of lesion site on functional recovery and the research literature reviewed will be discussed further in the fight of the findings of this study.

From the literature review it can be seen that a number of authors have attempted to establish links between factors such as age and severity of initial impairment and functional outcomes. However, the review has identified a considerable lack of consensus regarding the prognostic indicators for functional recovery. This may, as Blanc-Garin (1994) suggest, be due to the inter-individual variations between subjects together with the multi-faceted nature of recovery and or compensation or it may, in part, be due to the validity and reliability of the measures used.

Any study therefore into the effectiveness of either therapeutic interventions or comparisons of service provision and outcome must ensure that measures of effect are used that are patient orientated, reliable and valid. A further issue requiring review pertains to the concept of spontaneous recovery as there appears in the literature, to be conflicting opinions (Lind, 1982; Smith et al.,1981), regarding this process and the recovery of functions attributable to physiotherapy intervention.