References for this Review were identified through searches of PubMed, the Cochrane Library, and related articles from January, 1970, to September, 2009, by use of the terms “stroke and medical complications”, “cardiac complications of stroke”, “myocardial infarction and stroke”, “cardiac arrhythmias and stroke”, “congestive heart failure and stroke”, “infections and stroke”, “pneumonia and stroke”, “urinary tract infection and stroke”, “fever and stroke”, “venous thrombosis and stroke”,
ReviewMedical complications after stroke
Introduction
Stroke is a leading cause of death and disability worldwide. Medical complications are frequent among individuals who have had a stroke, increasing the length of hospitalisation as well as the costs of care. These complications are a major cause of death in the acute and subacute stroke phases.1, 2, 3 Pre-existing medical conditions, advanced age, and pre-stroke disability can affect an individual's risk for developing these events. Patients with severe, disabling strokes are particularly vulnerable.1, 4, 5, 6, 7 Medical complications can hinder functional recovery and are associated with poorer functional outcome after adjusting for stroke severity and age.1 The explanation for this association is unclear but these events probably interfere with rehabilitative therapies. Furthermore, fever, hyperglycaemia, systemic inflammatory response, hypoxia, or medications used to treat some of these complications might have a directly damaging physiological effect on an injured brain or might compromise its capability for plastic change.
Most medical complications develop within the first few weeks of stroke.1, 6, 8 Some events, such as cardiac abnormalities, dysphagia, and pneumonia, are often apparent early after stroke onset whereas others, such as bed sores, venous thrombosis, and falls, can occur after several days. Many complications are preventable or, when this is not possible, early recognition and treatment can be effective in ameliorating these events early in their course. Therapeutic dilemmas can arise when treatment of a systemic complication poses a potentially harmful effect on the stroke-injured brain. These situations require appropriate tailoring of management strategies after considering the risks and benefits of different treatment approaches. For example, an acute myocardial infarction after an acute stroke might require withholding of thrombolytic therapies and even modification of other coronary revascularisation procedures. Additional considerations could involve the choice of antiplatelet drug, whether to use β blockers, or which blood pressure goals to pursue. Other situations when standard management practices might need to be altered in the context of a new stroke could include the use of anticoagulants for treating deep vein thrombosis (DVT) or pulmonary embolism in patients with intracerebral haemorrhage or antithrombotic treatment in patients with ischaemic stroke and gastrointestinal haemorrhage.
Several investigators have systematically collected and analysed data on medical complications after stroke and others have focused on specific medical events after stroke. The reported frequency of such complications has varied (table) owing to differences in study designs and inception cohorts. Most studies have involved the collection of data from an inpatient cohort either in a hospital setting or at a rehabilitation facility, enrolling patients at different time points during their stroke recovery. Time to enrolment might have affected which complications were observed; studies that were done during rehabilitation are more likely to have omitted patients who died from either medical or neurological complications during hospitalisation. However, patients at rehabilitation facilities probably had more disabling strokes than patients who were discharged from hospital earlier, and patients with less severe deficits are likely to have been discharged earlier. Some investigators have relied on participants enrolled in a randomised controlled trial for analysis; in general, these individuals might have been healthier than patients who have been excluded from trial participation owing to substantial comorbidities. The criteria used for identifying complications have also varied across these studies—some have used a retrospective case ascertainment method from medical records whereas others were prospective but used different criteria. Despite these shortcomings, these reports provide useful insights into systemic medical complications in patients with stroke.
In this Review, we discuss some of the important medical complications after a stroke and highlight the relevant preventive and treatment aspects of care based on published data. We focus on non-neurological medical complications of stroke with an emphasis on those that occur in the acute and subacute phases of stroke recovery. Only major systemic medical complications are discussed; neurological complications such as seizures, encephalopathy, recurrent strokes, and some systemic complications such as hypertension and hyperglycaemia are beyond the scope of this paper and have not been included.
Section snippets
Cardiac complications
Stroke and ischaemic heart disease share several risk factors. Underlying cardiac diseases such as atrial fibrillation, valvular heart disease, or congestive heart failure increase the risk of stroke, and stroke can provoke disturbances in autonomic control and predispose patients to cardiac complications.10, 11, 12, 13, 14, 15 The occurrence of serious cardiac events and non-stroke vascular death in patients with stroke is therefore high.16 Data from the Virtual International Stroke Trials
Pneumonia
Pneumonia is one of the most frequent medical complications of stroke1, 2, 3, 4, 5, 6, 8, 9 and the most common cause of fever within the first 48 h after an acute stroke.1, 38 After adjusting for important confounders and covariates in individuals who have had stroke, pneumonia led to a threefold increased risk of death.39 Most stroke-related pneumonias are believed to result from aspiration:1 inhalation of colonised bacteria that seed pharyngeal material or that reside in the gingival
Dysphagia
Between 37% and 78% of patients with stroke develop dysphagia.45 This wide range indicates differences in study designs and investigative techniques that have been used to identify cases. Dysphagia leads to restriction of oral intake, putting patients at risk of undernutrition and dehydration. Dysphagia is also a major risk factor for stroke-associated pneumonia and is associated with poor outcomes and institutionalisation.43, 45 Although the swallowing centres are located in the lower
Urinary tract infections
Urinary tract infections are a frequent occurrence in patients with acute stroke.1, 2, 3, 4, 5, 6, 7, 8, 9 Increased age, use of urinary catheters, stroke severity,88, 89 and female sex89, 90 are independent predictors of urinary tract infections after a stroke. Most patients seem to have uncomplicated urinary tract infections;1, 7 some studies have found an association between urinary tract infections and poor outcome88, 89 but this association is attenuated when examined in the presence of
Deep vein thrombosis
DVT is a major concern in the post-stroke period, particularly in patients with limb paralysis. Older studies that used 125I-fibrinogen screening showed a high prevalence of DVT of about 50% within the first 2 weeks after a hemiparetic stroke, in the absence of thromboprophylaxis.98 The reported incidence is lower in studies that used venography and Doppler ultrasound.99 A prospective study that have used MRI for direct thrombus imaging of the lower extremities and pelvis detected venous
Hip fractures
Patients with stroke are at increased risk for fractures, particularly those that involve the hip joint.118, 119, 120 Hip fractures are associated with high morbidity and mortality in the elderly. In a large hospital-based study, the risk of fractures was found to be sevenfold higher during the first year after stroke, compared with the general population, and declined thereafter.121 This finding seems to coincide with an increase in mobility of patients during the first year after their stroke
Fatigue
Many patients report substantial fatigue after a stroke, which can cause functional limitations.143 Post-stroke fatigue has usually been attributed to an adjustment reaction or depression.144, 145 Patients with depression and severe disabilities seem to be at increased risk.146 The cause of post-stroke fatigue is probably multi-factorial. Physical deconditioning, associated medical ailments, and effects of medications are likely to play an important part. A recent population-based study has
Conclusions
Care of patients with stroke is often complicated by the occurrence of adverse medical events. These events not only affect the overall wellbeing of the patient but some complications, such as infections, pyrexia, and hypoxia, can have more directly injurious consequences on the brain. In recent years, there has been a rapid growth of modern stroke care units fuelled by reports of better outcomes of patients managed in these units.171 This improvement in outcomes has been largely attributed to
Search strategy and selection criteria
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