***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
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    ***EXAMPLES*** 
    Input: Background Dementia due to Alzheimer ’s disease ( AD ) and dementia with Lewy bodies ( DLB ) are the two most common neurodegenerative causes of dementia . They commonly occur together , especially in older people , but clinical identification of these diseases in dementia is difficult in such circumstances . We therefore conducted a study using cases with both comprehensive prospect i ve clinical assessment s and complete neuropathological examination to determine if it is possible to identify such mixed cases clinical ly and to determine features which may identify DLB in the presence of AD dementia . Methods At Newcastle Brain Bank we identified subjects who had a clinical diagnosis of dementia and who also had autopsy diagnoses of pure AD , pure DLB , or mixed AD+DLB . All subjects had undergone prospect i ve longitudinal clinical assessment s. Mixed AD+DLB patients met neuropathological criteria for both DLB ( limbic/neocortical Lewy body disease ) and AD ( Braak stage V/VI and CERAD B/C ) . The records of these subjects were carefully review ed by two specialists in old-age psychiatry blind to autopsy findings to determine baseline and final clinical diagnoses based on these detailed records . The presence of characteristic Lewy body symptoms and other clinical information was also recorded . Results Of 59 subjects included , 19 were AD , 18 DLB , and 22 mixed AD+DLB . At baseline no subjects were correctly identified as having mixed AD+DLB and by final diagnosis only 23 % were identified . The only symptom which helped in identifying the presence of Lewy body disease in the context of a mixed AD+DLB dementia was complex visual hallucinations . Conclusions Whilst the identification of DLB in the context of a dementia with an AD pattern is difficult , the emergence of complex visual hallucinations in the context of such a degenerative dementia suggests the presence of Lewy body disease and should encourage a careful assessment . Biomarkers appear likely to be necessary to help improve identification of different disease subtypes underlying dementia Background Falls are a major cause of morbidity and mortality in dementia , but there have been no prospect i ve studies of risk factors for falling specific to this patient population , and no successful falls intervention/prevention trials . This prospect i ve study aim ed to identify modifiable risk factors for falling in older people with mild to moderate dementia . Methods and Findings 179 participants aged over 65 years were recruited from outpatient clinics in the UK ( 38 Alzheimer 's disease ( AD ) , 32 Vascular dementia ( VAD ) , 30 Dementia with Lewy bodies ( DLB ) , 40 Parkinson 's disease with dementia ( PDD ) , 39 healthy controls ) . A multifactorial assessment of baseline risk factors was performed and fall diaries were completed prospect ively for 12 months . Dementia participants experienced nearly 8 times more incident falls ( 9118/1000 person-years ) than controls ( 1023/1000 person-years ; incidence density ratio : 7.58 , 3.11–18.5 ) . In dementia , significant univariate predictors of sustaining at least one fall included diagnosis of Lewy body disorder ( proportional hazard ratio ( HR ) adjusted for age and sex : 3.33 , 2.11–5.26 ) , and history of falls in the preceding 12 months ( HR : 2.52 , 1.52–4.17 ) . In multivariate analyses , significant potentially modifiable predictors were symptomatic orthostatic hypotension ( HR : 2.13 , 1.19–3.80 ) , autonomic symptom score ( HR per point 0–36 : 1.055 , 1.012–1.099 ) , and Cornell depression score ( HR per point 0–40 : 1.053 , 1.01–1.099 ) . Higher levels of physical activity were protective ( HR per point 0–9 : 0.827 , 0.716–0.956 ) . Conclusions The management of symptomatic orthostatic hypotension , autonomic symptoms and depression , and the encouragement of physical activity may provide the core elements for the most fruitful strategy to reduce falls in people with dementia . R and omised controlled trials to assess such a strategy are a priority Auteur(s ) : Jacques Boddaert , Marc Verny La responsabilite de la maladie d’Alzheimer ( MA ) dans les gr and es causes de mortalite a ete suggeree par differentes etudes , et differents facteurs pejoratifs ont ete rapportes , tels que le sexe masculin , la severite initiale de la maladie , l’existence de troubles du comportement , de deambulation ou de chutes , et la presence de signes extrapyramidaux . Les donnees de la litterature sont assez variables , selon que l’on parle de debut de la maladie , et dans ce cas selon les criteres que l’on retient pour le definir , ou de date du diagnostic . De meme , l’evolutivite du declin cognitif doit etre prise en compte , comme le confirme l’etude de Hui et al. sur 354 patients avec une MA suivis sur une periode 4 ans [ 1 ] . Degre de complexite supplementaire chez le gr and vieillard polypathologique , les nombreuses comorbidites associees jouent probablement un role determinant dans la survie de ces patients , et parler de survie de la MA dem and e une prise en compte de tous ces parametres confondants . Wolfson et al. , a partir de la Canadian study of health and aging ( CSHA ) , avaient etudie la survie de la MA en 2001 en considerant le debut de la maladie d’Alzheimer diagnostique par 3 questions de la Camdex ( Cambridge examination for mental disorders of the elderly ) . Ces auteurs avaient rapporte une mediane de survie de 3,1 ans chez des patients âges ( 83 + /- 7 ans ) avec MA , en utilisant des ajustements pour le biais de duree d’evolution , le sexe , le niveau d’education et l’âge au moment du diagnostic , qui restait , apres regression logistique , le facteur de plus mauvais pronostic [ 2 ] . Recemment , Larson et al. ont publie de nouveaux result ats sur le sujet [ 3 ] . Il s’agit d’une etude observationnelle prospect i ve , a partir de 23 000 patients âges de 60 ans ou plus engages dans un programme de sante , suivis de 1987 a 1996 , permettant d’etudier l’histoire naturelle de la MA dans les cas incidents . Durant la periode de l’etude , 970 patients ont ete explores pour un syndrome dementiel . Parmi eux , 521 nouveaux cas de MA ont ete diagnostiques , comprenant 431 cas probables et 90 cas de MA possible selon les criteres du DSM-III-R et NINCDS-ADRDA , avec un suivi moyen de 5,2 ± 3,1 ans . Les scores au MMS au moment du diagnostic se repartissaient en 17 % entre 25 et 30 , 24 % entre 22 et 24 , 30 % entre 18 et 21 et 30 % ≤ 17 . Les scores relativement bas de MMS ( 60 % ≤ 21 ) sont dus aux modes de recrutement ( patients entrant dans le registre s’ils recevaient des soins ) et a ceux du reperage des symptomes de demence ( troubles mnesiques , confusion ou deambulation ... ) . La mediane de survie des patients a partir du diagnostic de la maladie etait influencee par de nombreux facteurs . Elle passait de 4,2 ans pour les hommes a 5,7 ans pour les femmes , confirmant le caractere pejoratif du sexe masculin . Concernant les comorbidites , cette etude soulignait le role d’une cardiopathie ischemique ( p < 0,001 ) , d’une insuffisance cardiaque ( p < 0,001 ) , du diabete ( p = 0,04 ) et d’un antecedent d’accident vasculaire cerebral ( p = 0,026 ) associes . Par contre , l’hypertension arterielle , consideree comme representant un facteur de declin de la MA , n’influencait pas la maladie . En analyse multivariee , ajustee pour l’âge , le sexe , l’origine ethnique , l’existence d’une cardiopathie ischemique , d’une insuffisance cardiaque et d’un diabete , le deces etait correle : 1 ) au score MMSE au moment du diagnostic ( ≤ 17 : hazard ratio 2,67 [ 1,94 - 3,66 ] , p < 0,001 ) ; 2 ) au score DRS ( entre 5,5 et 17 : hazard ratio 2,04 [ 1,54 - 2,71 , p < 0,001 ) ; 3 ) aux signes  frontaux  ( hazard ratio 1,27 [ 1,03 - 1,55 ] , p = 0,022 ) ; 4 ) aux signes extrapyramidaux ( hazard ratio 1,35 [ 1,03 - 1,76 ] , p = 0,028 ) ; 5 ) aux troubles de l’humeur ( hazard ratio 1,4 [ 1,12 - 1,76 ] , p = 0,004 ) , 6/ a la deambulation ( hazard ratio 1,45 [ 1,02 - 2,08 ] , p = 0,04 ) . Le declin de plus de 5 points de MMS par an etait egalement associe a une mortalite augmentee . En comparant les result ats de l’etude aux donnees de la mortalite dans la population des Etats-Unis , les patients atteints d’une MA avaient constamment une reduction de l’esperance de vie . Les causes de deces ne sont pas rapportees . La correlation inverse entre mortalite et score au MMS reflete probablement la duree d’evolution de la maladie et l’on peut s’interroger sur l’impact d’une prise en charge globale et plus encore medicamenteuse chez ces patients . Cette etude souligne l ’ importance des comorbidites dans la MA du sujet âge , et est utile pour le clinicien , en particulier pour decider de la mise en place de therapeutiques lourdes . De plus , la mise en evidence de facteurs pejoratifs associes permet de cibler une population plus a risque et d’adapter au mieux surveillance et traitements . La limitation principale de cette etude concerne le mode de recrutement et le caractere non representatif de la population dans son ensemble . De nouvelles etudes , idealement en population , devront preciser la duree de vie des malades atteints d’une maladie d’Alzheimer et evaluer l’impact sur la survie des therapeutiques symptomatiques de la MA ou des traitements des comorbidites . 1 . Hui JS , Wilson RS , Bennett DA , Bienias JL , Gilley DW , Evans DA . Rate of cognitive decline and mortality in Alzheimer ’s disease . Neurology 2003 ; 61 : 1356 - 61 . 2 . Wolfson C , Wolfson DB , Asgharian M , M’Lan CE , Ostbye T , Rockwood K , et al. Clinical Progression of Dementia Study Group . A reevaluation of the duration of survival after the onset of dementia . N Engl J Med 2001 ; 344 : 1111- 6 . 3 . Larson EB , Shadlen MF , Wang L , McCormick WC , Bowen JD , Teri L , et al. Survival after initial diagnosis of Alzheimer disease . Ann Intern Med 2004 ; 140 : 501 - 9 Introduction Autonomic dysfunction is a well-known feature in neurodegenerative dementias , especially common in α-synucleinopathies like dementia with Lewy bodies and Parkinson 's disease with dementia . The most common symptoms are orthostatic hypotension , incontinence and constipation , but its relevance in clinical practice is poorly understood . There are no earlier studies addressing the influence of autonomic dysfunction on clinical course and survival . The aim of this study was to investigate the frequency of the three most common features of autonomic dysfunction and analyze how it affects survival . Methods Thirty patients with dementia with Lewy bodies and Parkinson 's disease with dementia were included in this prospect i ve , longitudinal follow-up study . Presence of incontinence and constipation was recorded at baseline .  Blood pressure was measured at baseline , after 3 months and after 6 months according to st and ardized procedures , with 5 measurements during 10 minutes after rising . Orthostatic hypotension was defined using consensus definitions and persistent orthostatic hypotension was defined as 5 or more measurements with orthostatic hypotension . Difference in survival was analyzed 36 months after baseline . Results There was a high frequency of persistent orthostatic blood pressure ( 50 % ) , constipation ( 30 % ) and incontinence ( 30 % ) . Patients with persistent orthostatic hypotension had a significantly shorter survival compared to those with no or non-persistent orthostatic hypotension ( Log rank x2 = 4.47 , p = 0.034 ) . Patients with constipation and /or urinary incontinence  , in addition to persistent orthostatic hypotension , had a poorer prognosis compared to those with isolated persistent orthostatic hypotension or no orthostatic hypotension ( Log rank x 
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Differences in survival were not explained by follow-up time , age at diagnosis , gender , or cognitive score .
There is consistent evidence for higher and earlier mortality in DLB compared to AD .