Cognitive impairment and congestive heart failure 33-36

Nursing knowledge in integrated care38-41

Continuing professional developmentThe contents of the resuscitation trolley

43-52

Multiple-choice self-assessment 54

Practice profile assessment 55

Author guidelines 56Guidelines on writing for Nursing Standards art&science section

Lackey J (2004) Cognitive impairment and congestive heart failure. Nursing Standard. 18, 44, 33-36. Date of acceptance: May 15 2004.

Cognitive impairment andcongestive heart failure

CONGESTIVE HEART failure is a complex syn-drome that results from any structural orfunctional cardiac disorder that impairs theability of the heart to function as a pump (Cowieand Zaphiriou 2002). The management of heartfailure has become a great challenge to the NHSin recent years due to a rising older populationand greater survival rates from acute myocardialinfarction.

Congestive heart failure is a burden on the bud-get of most healthcare systems in the developedworld. Cowie and Zaphiriou (2002) report that con-gestive heart failure accounts for between 1 and 2per cent of healthcare expenditure in the UK. Rogerset al (2000) note its significance as the main cardio-vascular disease, with increasing rates of incidenceand prevalence. The National Service Frameworkfor Coronary Heart Disease (DoH 2000) has addressedthe needs of a rising older population by standar-dising treatment for heart failure to lower mortal-ity and improve quality of life.

When caring for and treating patients with heartfailure, there is a tendency to focus on the physi-cal manifestations of the disease. In the acute set-ting, when the patient is critically ill, physicalstabilisation is paramount. However, having sta-bilised the patient, mental assessment can oftenbe overlooked, even though the reason for admis-sion may have been of a cognitive nature, such asinability to cope with treatment regimens. Lack ofmental assessment may become evident when thepatient demonstrates memory problems, leadingto poor compliance with medication and reducedself-management (Rogers et al 2000). Cognitionrefers to mental activities related to thinking, mem-ory and learning (Riegal et al 2002). This suggeststhat impaired cognition should be suspected whena patient displays changes in memory, judgement,personality or ability to complete usual activities.These traits are often observed in patients withheart failure (Riegal et al 2002).

Almeida and Flicker (2001) report that as manyas 80 per cent of patients with severe heart failureexhibit memory deficits and other cognitive dys-function such as attention deficits. Many patientswith heart failure are older and age can be an inde-pendent cause of poor cognition. Zuccala et al(1997) studied cognitive dysfunction in older patientswith mild to moderate heart failure. They foundimpairment to be common and independently asso-ciated with lower left ventricular ejection fraction.Interestingly, they also reported that deficits werefound in younger patients awaiting cardiac trans-plantation. As with older patients, these deficitswere attributed to reduced cerebral blood flow.

Almeida and Flicker (2001) acknowledge that low

The link between congestive heart failureand cognitive impairment

july 14/vol18/no44/2004 nursing standard 33

Joanne Lackey RN, BA(Hons), Dip HE, is a sister on theCoronary Care Unit, UniversityHospital Aintree, Liverpool. Email:joanne.lackey@aht.nwest.nhs.uk

Cardiovascular disorders

Cognitive impairment

Patient assessment

These key words are based on the subject headings fromthe British Nursing Index. This article has been subject to double-blind review.

Key words

Background The course of heart failure canbe unpredictable and uncontrolledsymptoms are the main problem. This reviewanalyses the current literature surroundingcognitive impairment and heart failure withspecial emphasis on self-management andquality of life. It attempts to explain theextent to which compliance and self-management contribute to acutehospitalisation, and to what extent thepatients mental capability influencescompliance with treatment.Conclusion The literature identifies a linkbetween congestive heart failure and cognitive impairment.

Abstract

art&scienceclinical research education

For related articles and authorguidelines visit our onlinearchive at:www.nursing-standard.co.ukand search using the key words below.

Online archive

p33-36w44 7/6/04 2:48 PM Page 33

34 nursing standard july 14/vol18/no44/2004

art&scienceliterature review

ejection fraction and cardiac output might causeimpaired cognition. It could be possible that co-morbidity also contributes to cognitive dysfunction,and that atrial fibrillation, for example, could causeproblems with cognition as a consequence ofischaemic heart disease. Cerebrovascular diseasehas been identified as another likely cause of cog-nitive impairment, and Almeida and Flicker (2001)suggest that this is because many patients with congestive heart failure also have other cardiovas-cular complications and are at increased risk ofdeveloping stroke. Other possible causes have beenemphasised in the literature. Riegal et al (2002)considered nutritional deficiencies, depression,infection and dehydration as potential causes forcognitive impairment but found no association.Zuccala et al (1997) found that depression wascommon in older people but it was not associatedwith cognitive performance.

Riegal et al (2002) acknowledge that other pos-sible mechanisms for cognitive impairment deservefurther investigation. These include white matterlesions from silent cerebral infarction and increasesin haemodynamic pressure, for example, right atrialpressure. Taylor and Stott (2002) also found theissue of cerebral circulation an important one. Theysuggest that low-grade cerebral ischaemia couldbe attributed to congestive heart failure, but alsoto age and low systolic blood pressure. The authorshighlight the hypercoagulable state associated withcongestive heart failure and suggest that abnor-malities in haemostasis and thrombosis may beimportant factors in the pathogenesis of ischaemicdamage (Taylor and Stott 2002). This demonstratesthe many variables that may contribute to impairedcognition rather than congestive heart failure inisolation.

The causes of cognitive impairment in heart fail-ure remain unclear, and may be the result of a com-bination of pathophysiological disturbances. Therole of systolic blood pressure is a dominant themein the literature. In a large prospective study thatexamined whether arterial hypotension might beassociated with cognitive impairment among olderparticipants with heart failure, Zuccala et al (2001a)found that systolic hypotension was selectively asso-ciated with cognitive impairment among this group.Riegal et al (2002) also highlight the correlating fac-tor of systolic hypotension despite the constraintsof a relatively small study with a limited sample size.

Hence the literature, though limited, suggeststhere is a strong link between cognitive impairmentand heart failure (Almeida and Tamai 2001a, Antonelliet al 2003, Riegal et al 2002), yet acknowledgesthat further studies are required to determine defin-itive causes. Importantly, the literature provokesexamination of the impact of cognitive impairmenton the individual and their carers, and whether itcould affect morbidity and mortality. Almeida andFlicker (2001) report that up to 80 per cent of

patients with severe congestive heart failure dis-play deficits in memory and other cognitive abili-ties that could affect morbidity and mortality. It alsoraises the question of how well healthcare profes-sionals are detecting and treating this neglectedaspect of congestive heart failure.

Zuccala et al (1997) found the biggest deficit incognition to be that of complex reasoning. Theyreport that the same deficits had been identified inyounger patients who were awaiting cardiactransplantation. In a qualitative, interview-basedstudy by Rogers et al (2000), confusion and short-term memory loss were reported to be the mainsymptoms of heart failure, strongly affecting com-munication, in particular their ability to ask pre-planned questions of clinicians. Grubb et al (2000)relate memory loss with anxiety and depressionspecifically to problems with compliance and adher-ence to complex treatment regimens. In contrastto other researchers in the field, they state thatcognitive function, including memory, could beaffected by anxiety and depressive states (Grubbet al 2000). Antonelli et al (2003) recently assessedverbal memory impairment in patients with heartfailure, finding it to be uniformly high in patientswith moderate to severe heart failure. However,the authors stressed that screening methods forcognitive dysfunction were not yet accurate.

Impaired cognition affects patients and their car-ers in the day-to-day management of their condi-tion. Surveys indicate that physical, social, work andleisure activities are significantly impaired amongpatients with congestive heart failure (Almeida andTamai 2001b). Cognitive impairment may furtherincrease morbidity and mortality in this patientgroup (Almeida and Tamai 2001b). This insight hasgreat implications for the service provided for thesepatients, for example, offering them exercise forcardiac rehabilitation. From both an ethical andmoral perspective, it is important to assess the men-tal state of heart failure patients alongside theirphysical symptoms, and also to determine the effectsof cognitive impairment on self-management.

Working in the acute setting, communicating withpatients with heart failure, especially in relation totissue hypoxia and the ability to follow instructionsand comprehend treatment regimens, is complexand requires a skilled and sensitive approach topatient care. This highlights the important issue ofconsent, especially relating to invasive procedureswhen a patient may be cerebrally compromised.Following discharge, this can affect long-term day-

Cognitive impairment and self-management in heart failure

The impact of cognitive impairment inheart failure

p33-36w44 7/6/04 2:48 PM Page 34

to-day management of the disease, such as fol-lowing instructions regarding medication doses andfluid management. Cowie and Zaphiriou (2002)emphasise the benefits of patient focus groups toaid understanding of cardiovascular disease. Theysuggest that discussions will improve patients under-standing of the condition and will help to empowerthem to adopt a more active role in their care andmanagement (Cowie and Zaphiriou 2002).

Rogers et al (2000) discuss how patients with con-gestive heart failure find it difficult to absorb andretain information and may not appreciate its rel-evance. Patients in this qualitative, interview-basedstudy blamed confusion or short-term memory lossfor their inability to ask planned questions of theirclinicians. Fatigue also played a role and manypatients were unaware of what heart failure actu-ally was and the likely prognosis (Rogers et al 2000).Inability to remember and assimilate informationmay be contributing to the high readmission ratesseen with heart failure. Carlson et al (2001) sug-gest that self-care is difficult because of the func-tionally compromised position of the patients. Thepatients knowledge is often poor and misconcep-tions are evident, leading to low confidence andhigh readmission rates. A similar view is shared byEkman et al (2002) who discuss the impact of severecongestive heart failure on older patients. Theyfound that these variables, that is, being older andhaving congestive heart failure, were especially asso-ciated with limited functional abilities and impairedquality of life.

This emphasises how important it is for hospitaland community nurses to maintain stability in thesepatients. The main factor in maintaining stability iscompliance with treatment regimens. Cline et al(1999) assessed concordance with prescribed med-ication in older patients with heart failure. Theyidentified that only 55 per cent of patients couldcorrectly name their prescribed medication and 27per cent were found to be non-concordant. Effortswere made by healthcare professionals in the studyto provide adequate information but poor knowl-edge remained a problem. This reinforces the dif-ficulties facing practitioners in preventing hospitalreadmissions in this group of patients.

Identifying cognitive impairment and successfullytreating it is a huge challenge facing practitioners,especially in the community setting. Even if it is pos-itively diagnosed, the difficulty lies in treating andpossibly reversing symptoms in the presence of oldage, co-morbidity and a limited support network.

The role of the heart failure specialist nurse is vitalto the effective management of heart failure patientsin the hospital setting. Using nurse-led clinics manypatients are holistically assessed and monitored at

regular intervals. However, geographical variationsmay lessen effective liaison between hospital andcommunity settings, resulting in some patients notreceiving effective treatment. Bennett et al (2000)advocate the use of focus groups to improve symp-tom management but limited resources may pre-vent this. Rogers et al (2000) emphasise difficultiesencountered by heart failure patients, including theuse of public transport, walking over distances andintolerance of crowds.

Other barriers to assessing and detecting cogni-tive dysfunction include time, resources, availabil-ity of skilled practitioners and consensus on the useof effective assessment tools (Swain et al 1999).The mini-mental state examination (MMSE) is usedin most of the reviewed studies. Swain et al (1999)compared the abbreviated mental test (AMT) withthe MMSE in assessing hospitalised patients andfound that the AMT was more useful in assessingcognitive function.

Riegal et al (2002) explored four screening mea-sures of cognitive impairment in heart failure patients.They found that no single screening test was suf-ficient to detect cognitive impairment, perhaps dueto the impairment being early or intermittent. Theydid, however, advocate the draw-a-clock test asthe most effective method of assessing commu-nity-based patients with early impairment. Researchon such screening methods is limited and promptinvestigation is needed into cognitive tests, as earlydiagnosis appears paramount.

Zuccala et al (1997) state that dementia in advancedage may be prevented or delayed by early detec-tion of cognitive impairment combined with promptintensive treatment of left ventricular systolic dys-function. Watson and Gibbs (2000) highlight howsymptom progression in heart failure patients maybe delayed by the initiation of angiotensin con-verting enzyme (ACE) inhibitors. This may suggestthat such treatment may also delay the onset ofcognitive impairment in heart failure if poor cog-nition can be purely attributed to left ventriculardysfunction. Grubb et al (2000) indicate that anx-iety, depression and cardiovascular disease are influ-encing factors in cognition. With so many possibleaetiologies for poor cognition, controversy existsas to whether maximising heart failure treatmentcan improve cognition. Studies on the reversal ofcognitive dysfunction are limited. Almeida and Tamai(2001b) set out to demonstrate this by showingthat increasing medical treatment over six weeksimproved attention scores in heart failure patients.In a further study in 2001, they studied hospitalisedpatients and felt that other factors such as co-mor-bidity and age affected cognition, recommendingthat future studies should clarify mechanisms ofimpaired cognition as well as offering strategies toprevent and treat deficits (Almeida and Tamai 2001a).

Taylor and Stott (2002) question whether cogni-tion can be improved in heart failure patients. The

Barriers to successful screening and treatment of poor cognition

july 14/vol18/no44/2004 nursing standard 35

art&scienceliterature review

p33-36w44 7/6/04 2:48 PM Page 35

There is a link betweencongestive heart failure andcognitive impairment.

Early assessment anddiagnosis are vital.

There is a case for increasednumbers of community heart failure nurses to screen patients for impaired cognition and treat them early.

Implications for practiceonly clear positive data as yet relates to improvedcognition following cardiac transplantation. Putzkeet al (1998) found that haemodynamic pressurevariables were consistently inversely related to cog-nitive functioning among heart transplant candi-dates with improvement following surgery. Furtherstudies may yield some interesting results in thefuture. Results are awaited from a study usingperindopril with older heart failure patients and theeffect of ACE inhibition on cognitive change (Taylorand Stott 2002).

The literature shows a positive link between con-gestive heart failure and cognitive impairment, to agreater or lesser extent. Despite the increased preva-lence of heart failure, the significance of this remainswidely unrecognised by health professionals. Sanghaet al (2002) suggest that by ignoring cognitive dys-function the patient becomes less self-reliant, ulti-mately resulting in increased mortality. Zuccala et al(2001b) emphasise the overwhelming challenge itposes to patients, carers and public health services.Although the exact cause remains unclear, the lit-erature advocates early assessment and diagnosisso treatment can be initiated to prevent prematuremorbidity and mortality (Almeida and Tamai 2001b,Zuccala et al 2001b). It also urges recognition ofpsychological illness as a common side effect ofcardiovascular disease (Grubb et al 2000). As the

incidence of heart failure increases and the litera-ture becomes more widely available, healthcareprofessionals should embrace this neglected area.Quality of life, disability and cognitive impairmentare complex areas and are more time consumingto measure than mortality or days of hospitalisa-tion (Taylor and Stott 2002). Further long-termresearch needs to be initiated to promote goodquality care and to enhance the quality of life forpatients with cognitive impairment and heart fail-ure. Although there are often time and workloadconstraints, rather than concentrating purely onphysical problems, nurses in the acute setting shouldbe assessing mental capability more deeply, and ini-tiating prompt referral to specialists when neces-sary. Clinical psychologists may be underused in thehospital setting where the causes of heart failureadmissions are often psychological in nature.

The findings of this literature review also provideevidence for increased numbers of community heartfailure nurses to screen patients for impaired cog-nition and treat early and appropriately, thus pre-venting needless hospital admissions. From an ethicalperspective, this aspect of heart failure assessmentshould be addressed if positive implications for mor-bidity and mortality are to be more definitely con-firmed. Riegal et al (2002) conclude by highlightingthe need for future research into this branch ofheart failure to improve screening methods, extendknowledge and ultimately prevent and manage thisproblem successfully

Conclusion

36 nursing standard july 14/vol18/no44/2004

art&scienceliterature review

REFERENCESAlmeida O, Flicker L (2001) The mind of

a failing heart: a systematic reviewof the association betweencongestive heart failure andcognitive functioning. InternationalMedical Journal. 31, 5, 290.

Almeida O, Tamai S (2001a) Congestiveheart failure and cognitivefunctioning amongst older adults.Arquivous de Neuro-Psiquiatria.59, 2B, 324-329.

Almeida O, Tamai S (2001b) Clinicaltreatment reverses attentionaldeficits in congestive heart failure.BMC Geriatrics. 1, 1, 2.

Antonelli R et al (2003) Verbal memoryimpairment in congestive heartfailure. Journal of ClinicalNeuropsychology. 25, 1, 14-23.

Bennett S et al (2000) Self-carestrategies for symptommanagement in patients withchronic heart failure. NursingResearch. 49, 3, 139-145.

Carlson B et al (2001) Self-care abilitiesof patients with heart failure. Heartand Lung. 30, 5, 351-359.

Cline et al (1999) Non-compliance andknowledge of prescribed medicationin elderly patients with heart failure.European Journal of Heart Failure.1, 2, 145-149.

Cowie M, Zaphiriou A (2002)Management of chronic heart

failure. British Medical Journal. 325,7361, 422-425.

Department of Health (2000) NationalService Framework for CoronaryHeart Disease. London, TheStationery Office.

Ekman I et al (2002) Health-relatedquality of life and sense ofcoherence among elderly patientswith severe chronic heart failure incomparison with healthy controls.Heart and Lung. 31, 2, 94-101.

Grubb N et al (2000) Memory functionin patients with stable, moderate tosevere cardiac failure. AmericanHeart Journal. 140, 1, 1-8.

Putzke J et al (1998) The relationshipbetween cardiac function andneuropsychological status amongheart transplant candidates. Journalof Cardiac Failure. 4, 4, 295-303.

Riegal B et al (2002) Cognitiveimpairment in heart failure: issues of measurement and etiology.American Journal of Critical Care.11, 6, 520-528.

Rogers A et al (2000) Knowledge andcommunication difficulties forpatients with chronic heart failure:qualitative study. British MedicalJournal. 321, 7261, 605-607.

Sangha et al (2002) Difficult cases inheart failure: the challenge ofneurocognitive dysfunction in severeheart failure. Congestive Heart

Failure. 8, 4, 232-234.Swain D et al (1999) Cognitive

assessment in elderly patientsadmitted to hospital: relationshipbetween the Abbreviated MentalTest and the Mini Mental StateExamination. Clinical Rehabilitation.13, 6, 503-508.

Taylor J, Stott D (2002) Chronic heartfailure and cognitive impairment: co-existence of conditions or trueassociation? European Journal ofHeart Failure. 4, 1, 7-9.

Watson R, Gibbs C (2000) ABC of heart failure: clinical features andcomplications. British MedicalJournal. 320, 7229, 236-239.

Zuccala G et al (2001a) Hypotensionand cognitive impairment; selectiveassociation in patients with heartfailure. Neurology. 57, 11, 1986-1992.

Zuccala G et al (2001b) Cognitivedysfunction as a major determinantof disability in patients with heartfailure: results from a multicentresurvey. Journal of Neurology,Neurosurgery and Psychiatry.70, 1, 109-112.

Zuccala G et al (1997) Left ventriculardysfunction: a clue to cognitiveimpairment in older patients withheart failure. Journal of Neurology,Neurosurgery and Psychiatry.63, 4, 509-512.

p33-36w44 7/6/04 2:48 PM Page 36