The Impairment Caused by a Stroke

Suffering from a stroke is one of the worst medical conditions to be plagued by. Caplan and Billar (2018), state that stroke brings with it lifelong impairment that can be difficult to recover from even after undergoing much therapy for this purpose (Caplan and Billar 2018). According to Tan and Markus (2015), a stroke is a crippling ailment, and once it does occur for a patient, doctors try their best to come up with ways and means by which the risk of stroke can be minimized for the future (Tan and Markus 2015).  In the view of Flegel et al. (1987), people who suffer from a stroke can die in the first instance, and if they are lucky enough to survive, can die in the second or third instance. Hence the risk of encountering a stroke in the future has to be minimized at all costs (Flegel et al. 1987). This essay examines important literature undertaken to determine whether it is aspirin or heparin that proves to be more effective when reducing the recurrence of a stroke. The essay concludes that aspirin proves to be far more effective than heparin could ever be for recurrent stroke reduction, based on the results of the research reviewed for this purpose.

Robert Hart (2003), argues, that for neurologists, patients of atrial fibrillation who have suffered from a transient ischaemic attack or ischaemic stroke, suffering a very high chance of suffering from recurrent stroke (Hart 2003). He points out how such patients need to be treated over the long term with an adjusted dose of warfarin for the purpose of secondary prevention of stroke. He goes onto say that for the acute and adequate management of such patients, aspirin needs to be administered right until therapeutic anticoagulation has been successfully achieved (Hart 2003). Robert Harts states very clearly in his research that aspirin is capable of reducing the recurrence of a stroke by as much as twenty percent but that it should ideally be used for patients who are at a low risk of suffering from a recurrent stroke (Hart 2003). For high risk patients, he believes that the administering of adjusted warfarin will prove to be far more effective. He argues that adjusted warfarin proves to be particularly successfully in reducing the onset of a recurrent stroke for patients who already have cerebral ischaemia (Hart 2003). In other words, adjusted warfarin helps patients who are already suffering from stroke like conditions or have suffering one stroke at least,  in the first place instead of actually preventing the occurrence of a stroke (Hart 2003). Robert Harts goes on to point out the pros and cons of adjusted warfarin and aspirin both, arguing how the latter constitutes a far safe method of treating a stroke, especially for preventing the recurrence of a stroke compared to the former (Hart 2003).  He also refers to the use of heparin to reduce recurrent strokes in his research, arguing that while heparin has been traditionally considered an important drug for stroke reduction, two randomized clinical trials have challenged this practice (Hart 2003). Based on these randomized trials, it was seen that heparin does not bring about any improvement for patients suffering from stroke nor does it bring about any reduction in stroke recurrence (Hart 2003). Hart concludes that only adjusted warfarin and aspirin can be regarded as the two drugs that can bring about stroke reduction and that more clinical research is needed to locate drugs that are safer than adjusted warfarin and far more effective than aspirin, for reducing the recurrence of a stroke (Hart 2003).

Research on Recurrent Stroke Reduction

Hans Christoph Diener (2018), mentions in his research, the famous TOPAS study that was carried out for the purpose of studying the efficacy and safety of using heparin certoparin during a double blind and randomized multicenter dose finding trial that experimented on patients suffering from acute ischemic stroke (Diener 2018).  He talks about how as many as four hundred of these patients were randomized into four different treatment group and that too within a time-frame of twelve hours since the onset of the stroke (Diener 2018). One treatment group administered 8000 u axa or certoparinn heparin two times every single day, the second treatment group administered 5000 u axa two times every day, the third group administered 3000 u axa twice every day and the fourth group administered 3000 u axa certoparin once every single day (Diener 2018). For this experiment, the main efficacy variable constituted proportion of patients who reached favorable functional outcomes within three months. At the clinical trial entry, computed tomography was performed, both after a period of seven days as well as upon clinical deterioration (Diener 2018). It was seen as a result of this trial study that in the course of the certoparin heparin treatment, just one single deep vein thrombosis situation was evident. No pulmonary embolism could be detected (Diener 2018).  Hans-Christoph Diener concludes that increasing the dosage of certoparin heparin of 8000 uxa from being administered once daily to being administered twice daily did not bring about any improvement in functional outcomes for patients suffering from conditions like ischemic stroke (Diener 2018).  It is also important to note in this respect that severe bleeding tended be a lot more frequent only for the group being administered the highest dose (Diener 2018). He thus goes onto argue that heparinoids or full dose heparin is something that cannot be recommended for patients who suffer from conditions like acute ischemic stroke. He states that whether the subgroups of patients who are at the risk of experiencing progressive strokes or who have cardiac sources of embolism could benefit or not is something that remains to be seen (Diener 2018). He does however firmly believe that the administration of a low dose of low molecular heparin can help in preventing conditions like pulmonary embolism and deep vein thrombosis (Diener 2018). 

According to Pereira and Brown (2000), acute stroke treatment that makes use of heparin or aspirin is something that was studied in great detail, during the Chinese Acute Stroke Trial (CAST) and during the International Stroke Trial (IST). As a part of both these trials as many as forty thousand patients were randomized altogether (Pereira and Brown 2000). By combining the results of both the trials it was seen that an aspirin dosage ranging between 150 to 300 miligram when administered within forty eight hours of the onset or occurrence of a stroke is what produced a significant but small improvement in outcome or death dependency (Pereira and Brown 2000). Four to six months after the onset of stroke, around one patient per hundred were treated (Pereira and Brown 2000). A significant reduction was seen the recurrent ischaemic strokes of similar degrees and which was not in any way associated with the significant rise in cerebral haemorrhage. Pereira and Brown (2000), thus argue, that aspirin is something that should be used only for early secondary prevention of recurrent stroke and that too after excluding the cerebral haemorrhage upon scanning the patient (Pereira and Brown 2000). They argue that heparin is not a substance that is capable of improving clinical outcomes for patients after a stroke and this applies even for patients who suffer from atrial fibrillation (Pereira and Brown 2000). They say that heparin was seen to decrease the recurrent ischaemic stroke quite significantly during the international stroke trial (IST), but this came at the expense of a very significant rise in cerebral haemorrhage. For Pereira and Brown (2000), heparinoids and heparins of low molecular weight are not really beneficial in any way. Heparin therefore cannot be regarded as useful for routine therapy when it is used to treat patients suffering from acute stroke. Pereira and Brown (2000), conclude by saying that if heparin is used for patients who went through an acute ischaemic stroke, it should be limited only to the patients who are at the risk of contracting deep vein thrombosis or any kind of early recurrence of a stroke. Only then can the application of heparin dose prove to be effective for stroke patients, and that too in a very mild and limited way (Pereira and Brown 2000).

Aspirin Helps Reduce Recurrence of Stroke

According to Rothwell et al (2016), the use of aspirin is something that is recommended greatly for the secondary prevention of a stroke following a transient ischaemic attack based on trials that demonstrate a thirteen percent reduction in the long term risks of recurrent strokes (Rothwell et al. 2016). They go onto argue that the risk of suffering from a recurrent stroke continues to be quite high but this is so only for the first few days following transient ischaemic attack (Rothwell et al. 2016). Observational studies in their view have demonstrated well enough how the administering of early medication can prove to be far more beneficial than long term trials when it comes to reducing recurrent strokes (Rothwell et al. 2016). The researchers specifically argue that the short term benefits associated with early aspirin dosage for patients suffering from transient ischaemic attacks, is something that has been greatly underestimated, and it requires further investigation (Rothwell et al. 2016). The researchers pooled data from as many as 15778 participants for the purpose of their study from as many as twelve trials of control versus aspirin in secondary prevention (Rothwell et al. 2016). It was seen that aspirin brought about a reduction in the six week risk period associated with recurrent ischaemic stroke by as much as sixty percent and that it disabled the possibility of any fatal ischaemic stroke by as much as seventy percent. The greatest benefit of aspirin dosage application was witnessed in patients suffering from minor strokes or transient ischaemic attacks (Rothwell et al. 2018). Aspirin was seen to have such an impact on the reduction of recurrent stroke largely due to substantial reductions in severity. Some further reductions could be seen in the recurrent of ischaemic stroke when aspirin was used from six to twelve weeks, but no benefit could be detected for the period after twelve weeks. Rothwell et al. (2016), thus conclude that medical treatment can greatly reduce risk of recurrent stroke and that aspirin can be identified as a key intervention here. The early benefits associated with the administration of aspirin to patients suffering from transient ischaemic attack needs to be studied in detail. Furthermore, they argue, that the unrecognized effect that aspirin can have on the severity of any early recurring stroke, and the diminishing benefits associated with its long term use both have important implications for deciphering future mechanisms or course of action (Rothwell et al. 2016). 

Chaturvedi et al. (2011) argue, that aspirin is by far the only possible antiplatelet agent that is capable of generating effective results when applied for the early treatment of patients suffering from acute ischaemic attacks or mild stroke. It works as a great form of secondary prevention for stroke (Chaturvedi et al. 2011). They state that while clopidogrel tends to be more effective than aspirin when it comes to preventing the endpoints of any ischemic stroke, vascular death or myocardial infarction, it is not known to be better than aspirin as far as the prevention of any recurrent stroke is concerned, in patients who are subjected to regular transient ischaemic attacks or stroke like conditions (Chaturvedi et al. 2011). They refer to the use of heparin for treating stroke and preventing the onset of any recurrent stroke in their research, and argue that the use of heparin for such treatment is something that has generated a great deal of controversy over the years, but the early reviews of the use of heparin seem to indicate that its application may be way more harmful and far less beneficial than it is thought to be (Chaturvedi et al. 2011). They also describe a study that comprised of seven trials constituting as many as four thousand and two hundred patients, where heparin was compared with other forms of treating stroke like the use of placebo or aspirin, with the heparin dose having been administered within a period of forty eight hours after the onset of a stroke (Chaturvedi et al. 2011). They argue that the study revealed that the reduction in recurrent stroke for patients was seen to be non significant over a period of seven to fourteen days. There was on other hand a substantial increase in the occurrence of symptomatic intracranial hemorrhages and similar rates of disability or death in the follow up studies that were undertaken (Chaturvedi et al. (2011). The researchers conclude by stating that patients who are at a very high risk of suffering from a recurrent stroke need to be treated with clopidogrel or aspirin for best results. The use of aspirin is characterized by mild side effects and it stands as a wonderful measure for preventing recurrent strokes if used in the early stages of treatment (Chaturvedi et al. 2011).

Robert Hart’s Research on Warfarin and Aspirin

In the view of Johnston et al (2016), after carrying out a double blind international trial on as many as 13, 199 patients suffering from non-severe ischemic stroke, it is Ticagrelor that proves to be far more in-effective than aspirin when it comes to reducing the recurrent of stroke in patients. Both the safety and the efficacy of ticagrelor application was tested as a part of this study when compared to the administering of aspirin (Johnston et al. 2016). It was found by the researchers that ticagrelor helped in controlling minimal or minor bleeding but when it came to efficacy in particular (Johnston et al. 2016). Ticagrelor had little or no impact on reducing the recurrence of a stroke in the same way that aspirin did, even though the impact that aspirin is known to have on patients in this respect is considered by researchers as one that is rather mild in nature (Johnston et al. 2016).

The research studies that have been discussed above clearly indicate that while there are many ways by which a recurrent stroke can be reduced by doctors for patients suffering from acute ischaemic attacks, it is aspirin that proves to be the most effective form of treatment. Heparin as the studies above indicate, bring about little or no improvement in recurrent stroke reduction, while other forms of treatment like adjusted warfarin can have a toxic impact on the body when used (Hart 2003; Chaturvedi et al. 211; Johnston et al. 2016; Rothwell et al. 2016). Aspirin is not only effective in reducing recurrent strokes but its impact is also quite mild. It does not trigger dangerous chemical consequences in the body of the patient when consumed (Rothwell et al. 2016). Aspirin is especially effective when it is used in the early stages of treating a patient who is suffering from or has suffered from a stroke (Rothwell et al. 2016). It may not bring any immediate relief for the patient who has gone through a stroke but it can certainly have a vital role to play in ensuring that the risk of the stroke has been well minimized (Chaturvedi et al. 2011). 

References:

Caplan, L. and Biller, J. eds., 2018. Uncommon causes of stroke. Cambridge University Press

Chaturvedi, G. and Abraham, A., 2011. What Is the Best Approach to Medical Therapy for Patients with Ischemic Stroke?. Hospitalist, 2011(5).

Fac.org.ar. (2018). Diener HC – Treatment of Acute Ischemic Stroke with Heparin. [online] Available at: https://www.fac.org.ar/scvc/llave/stroke/diener/dieneri.htm [Accessed 8 Oct. 2018].

Flegel, K.M., Shipley, M.J. and Rose, G., 1987. Risk of stroke in non-rheumatic atrial fibrillation. The Lancet, 329(8532), pp.526-529.

Hart, R.G., 2003. Secondary prevention of stroke in patients with atrial fibrillation: what every neurologist should know. Practical Neurology, 3(5), pp.260-267.

Johnston, S.C., Amarenco, P., Albers, G.W., Denison, H., Easton, J.D., Evans, S.R., Held, P., Jonasson, J., Minematsu, K., Molina, C.A. and Wang, Y., 2016. Ticagrelor versus aspirin in acute stroke or transient ischemic attack. New England Journal of Medicine, 375(1), pp.35-43.

Pereira, A.C. and Brown, M.M., 2000. Aspirin or heparin in acute stroke. British medical bulletin, 56(2), pp.413-421., pp.1577-1582.

Rothwell, P.M., Algra, A., Chen, Z., Diener, H.C., Norrving, B. and Mehta, Z., 2016. Effects of aspirin on risk and severity of early recurrent stroke after transient ischaemic attack and ischaemic stroke: time-course analysis of randomised trials. The Lancet, 388(10042), pp.365-375.

Tan, R.Y. and Markus, H.S., 2015. Monogenic causes of stroke: now and the future. Journal of neurology, 262(12), pp.2601-2616