
==== Front
Cereb Circ Cogn Behav
Cereb Circ Cogn Behav
Cerebral Circulation - Cognition and Behavior
2666-2450
Elsevier

S2666-2450(24)00166-1
10.1016/j.cccb.2024.100365
100365
Article
In memoriam, Timo Juha Erkinjuntti, MD PhD, Professor in Neurology, University of Helsinki, Finland
Pantoni Leonardo
Jokinen Hanna
Melkas Susanna
Kalaria Raj raj.kalaria@newcastle.ac.uk
⁎
on behalf of the
LADIS study, Helsinki Small Vessel Disease Study group and VasCog Society
Translational and Clinical Research Institute, Newcastle University, Campus for Ageing and Vitality, Newcastle upon Tyne NE4 5PL, United Kingdom
⁎ Corresponding author. raj.kalaria@newcastle.ac.uk
24 8 2024
2024
24 8 2024
7 1003656 8 2024
23 8 2024
23 8 2024
© 2024 The Authors. Published by Elsevier B.V.
2024

https://creativecommons.org/licenses/by-nc/4.0/ This is an open access article under the CC BY-NC license (http://creativecommons.org/licenses/by-nc/4.0/).
==== Body
pmcTimo Juha Erkinjuntti, Professor in Neurology at the University of Helsinki, sadly and prematurely passed away following a prolonged illness on Saturday 15th June at the age of 73 years. He is remembered as a dear friend, colleague, neurologist, scientist, mentor, teacher, sauna expert and more. Timo had also been the head physician in the Department of Neurology, Helsinki University Central Hospital. It has taken some of us several days for the reality to sink in that Timo will no longer be with us in person, although he will be in our memories for as long as we ourselves are alive (Fig. 1).Fig. 1 Professor Timo Erkinjuntti in recent years looking regal and immaculate.

Fig. 1

Besides worrying about clinical diagnoses, research was important to Timo. He was well known not only in Finland but internationally for his pace-setting work on vascular dementia (VaD), poststroke cognitive impairment, poststroke depression, subcortical vascular dementia, and also Alzheimer's disease (AD). Timo was an extraordinary mentor and an inspiring fountain of knowledge to all who had the privilege of working with him. His passion and thinking in tackling vascular cognitive impairment and cerebral small vessel disease have spurred many. His influence will long continue through his trainees and mentees. Timo gave many a young minds much encouragement in their early academic years that helped them to carve out successful careers. Often, he would raise curiosity in others rather than promote himself. His significant contributions to the collective projects have left an indelible mark, and his absence will be profoundly felt.

Timo was born in Helsinki. He obtained his Licentiate in Medicine, University of Helsinki in 1977. He was awarded his PhD in 1988 based on the thesis entitled Dementia: clinical diagnosis and differential diagnosis, with special reference to multi-infarct dementia. Timo was appointed Associate Professor in experimental and clinical neurology in 1988 and 1994, respectively. In the early days in Helsinki, he worked closely with Markku Kaste (eminent mentor in neurology), Raimo Sulkava (neurologist) and Matti Haltia (a prominent neuropathologist). Timo was appointed full professor of neurology in 2008 but between 1991 and 2007 he was the recipient of several prestigious fellowships and visiting professorial appointments including those at the University of Western Ontario and the John P. Robarts Research Institute (with Vladimir Hachinski and Henry Barnett), the Johan Wolfgang Goethe University in Frankfurt am Main and the Institute for Ageing and Health (now the Translational and Clinical Research Institute) at Newcastle University.

During 1991–1993, while in London, Ontario he developed a strong interest in the neurological and psychiatric sequalae of white matter disease and stroke injury. Upon return to Helsinki with the cooperation of colleagues he established the pivotal Helsinki Stroke Aging Memory Study (the SAM), which included stroke survivors. This important resource showed that a single explanation for poststroke dementia is not adequate and that multiple factors including dysphasia, major dominant stroke syndrome, host characteristics comprising education, and prior cerebrovascular disease, each independently contribute to the risk of developing dementia after stroke (Fig. 2). He was well known for his longitudinal studies on post-stroke cognitive decline and his NEJM paper [1] on the unreliability of diagnostic criteria for dementia was a landmark piece. He was also a contributor to several other studies including the timely Vantaa 85+ community-based project. In his native Finland, Timo was a strong advocate of brain health. He wrote that although memory disorders are most common among people over the age of 80, they can be diagnosed already in the forties. He conveyed that 7000–10,000 people in the community develop a memory disorder at working age, and protective measures should be strongly promoted.Fig. 2 Timo's thinking on how host factors played a role in dementia caused by vascular disease. Different vascular risk factors are responsible for producing the primary pathologies including infarcts, white matter changes and atrophy but additional host factors associated with age, genes, lifestyle as well as environment lead to cognitive impairment and frank dementia.

Fig. 2

From 1996 to 1998, Timo was chair of the European Task Force on Age-related White Matter Disorders, a research consortium that was instrumental to the establishment of the EU funded Leukoaraiosis And DISability (LADIS) study. The LADIS team have published >100 peer-reviewed papers [2]. Timo was a key player and an enormous inspirator and some of the first publications of the LADIS study were driven by him. He contributed in countless ways among which he believed that white matter lesions and incident lacunes may be covert but still increased risk of progressive cognitive impairment. Pursuing the matter of white matter connectivity, he led interesting studies of their kind on the association of corpus callosum atrophy and mental slowing or psychomotor speed and executive deficits.

Over some 20 years, Timo served on the executive committees and panels of numerous learned organisations including most notably as president of the Alzheimer's Disease International (ADI) conference in Helsinki in 1997. He served the World Federation of Neurology, Research Group on Dementia, Nordic Society for Research in Brain Ageing, American Academy of Neurology, American Heart Association Stroke Council, International Psychogeriatric Association, European Agency for the Evaluation of Medical Products, International Working Group on harmonisation of Dementia Drug Guidelines, ADI Medical Scientific Advisory Panel and the World Federation of Societies of Biological Psychiatry and Alzheimer Europe. However, we very much value his profound contributions as a founder member of the International Society for Vascular Behavioural and Cognitive Disorders (VasCog) established in 2003. In the early days, we recall how in his characteristic practical manner he implemented working groups for the better functioning of the VasCog Society. When he became ill and unable to bear long flights, VasCog officers had vowed to take VasCog to Timo in Helsinki but they never made it!

Close friends can recall how keen Timo was to define and refine clinical diagnostic criteria for VaD. He was also most concerned about the behavioural syndrome in VaD [3]. Timo was a key contributor to the NINDS-AIREN criteria [4], which have been widely used and even abused. However, prior to that and current refinements, Timo and his colleagues in Helsinki had showed that patients at postmortem exhibited 85% accuracy (in terms of multiple infarcts and general absence of neurofibrillary pathology) of the clinical diagnosis of VaD [5]. Timo's scholarship and stature as an international researcher is demonstrated by the >350 publications produced between 1984 and 2023 with some 42,500 citations. Timo was the editor of multiple books among which Vascular Cognitive Impairment, edited by Timo and Serge Gauthier (Montreal) in 2002 is often mentioned. His book written in 2003 with Maarit Huovinen and entitled Kun Muisti Pettää (When memory fails: memory disorders and dementia), is popular among many Finns. Timo was a consummate educator including his peers and fellows, stimulating and influencing colleagues on the importance of white matter disease and, in general, the relation between vascular risk factors and cognitive decline. He supervised at least 10 trainees to completion of their doctoral dissertations.

Timo was also a trialist undertaking many phase 2 and 3 trials. He was the principal investigator of the trial with galantamine in patients with a diagnosis of probable VaD or AD combined with cerebrovascular disease (AD plus VaD). He published the results from this timely trial in the Lancet which has been cited >1000 times [6]. It showed that galantamine had a therapeutic effect on all key areas of cognitive and non-cognitive abilities in patients with dementias and probably mixed pathologies.

Over the years, we can confidently recount many a stimulating debates and friendly discussions with wit and humor in excellent company. Forever enlightening and we never went away without learning something new about our work including diagnostic clues or how to introduce novel ideas in the investigation of white matter disease. He was full of ideas, especially when conversations lead that way concerning the vascular field even during the pleasant sauna sessions at his house in Helsinki. Some also have wonderful memories of spending time with the Erkinjuntti family. Timo is survived by his wife Riitta, equally a conscientious educator and Aino, Eeva and Tatu Erkinjuntti. We will miss his big smile, unique dressing style, warm personal and professional interest in every person he met and of course the saunas and fish dinners (Fig. 3). Softley spoken Timo will be remembered with fond memories as a true gentleman, scholar and bon viveur.Fig. 3 Timo with his characteristic style and smile at VasCog 2007 in San Antonio, Texas.

Fig. 3

CRediT authorship contribution statement

Leonardo Pantoni: Writing – review & editing, Writing – original draft, Conceptualization. Hanna Jokinen: Writing – review & editing, Conceptualization. Susanna Melkas: Writing – review & editing, Conceptualization. Raj Kalaria: Writing – review & editing, Writing – original draft, Conceptualization.

Declaration of competing interest

The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:

Professor Raj Kalaria reports financial support was provided by Newcastle University, Newcastle upon Tyne, UK. Professor Raj Kalaria reports a relationship with Newcastle University. Other authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Timo Juha Erkinjuntti 1951–2024
==== Refs
References

1 Erkinjuntti T. Ostbye T. Steenhuis R. Hachinski V. The effect of different diagnostic criteria on the prevalence of dementia N. Engl. J. Med. 337 1997 1667 1674 10.1056/NEJM199712043372306 9385127
2 The L.S.G. Poggesi A. Pantoni L. Inzitari D. Fazekas F. Ferro J. 2001-2011: A Decade of the LADIS (Leukoaraiosis And DISability) Study: What Have We Learned about White Matter Changes and Small-Vessel Disease? Cerebrovasc. Dis. 32 2011 577 588 10.1159/000334498
3 Erkinjuntti T. Clinical criteria for vascular dementia: the NINDS-AIREN criteria Dementia 5 1994 189 192 10.1159/000106721 8087178
4 Roman G.C. Tatemichi T.K. Erkinjuntti T. Cummings J.L. Masdeu J.C. Garcia J.H. Vascular dementia: diagnostic criteria for research studies. Report of the NINDS-AIREN International Workshop Neurology. 43 1993 250 260 10.1212/wnl.43.2.250 8094895
5 Erkinjuntti T. Haltia M. Palo J. Sulkava R. Paetau A. Accuracy of the clinical diagnosis of vascular dementia: a prospective clinical and post-mortem neuropathological study J. Neurol. Neurosurg. Psychiatry 51 1988 1037 1044 10.1136/jnnp.51.8.1037 3216206
6 Erkinjuntti T. Kurz A. Gauthier S. Bullock R. Lilienfeld S. Damaraju C.V. Efficacy of galantamine in probable vascular dementia and Alzheimer's disease combined with cerebrovascular disease: a randomised trial Lancet 359 2002 1283 1290 10.1016/S0140-6736(02)08267-3 11965273
