Peak width of skeletonized mean diffusivity and its association with age-related cognitive alterations and vascular risk factors

Bonnie Yin Ka Lam; Kam Tat Leung; Brian Yiu; Lei Zhao; J Matthijs Biesbroek; Lisa Au; Yumi Tang; Kai Wang; Yuhua Fan; Jian-Hui Fu; Qun Xu; Haiqing Song; Xiaolin Tian; Winnie Chiu Wing Chu; Jill Abrigo; Lin Shi; Ho Ko; Alexander Lau; Marco Duering; Adrian Wong; Vincent Chung Tong Mok

doi:10.1016/j.dadm.2019.09.003

Peak width of skeletonized mean diffusivity and its association with age-related cognitive alterations and vascular risk factors

Alzheimers Dement (Amst). 2019 Oct 25:11:721-729. doi: 10.1016/j.dadm.2019.09.003. eCollection 2019 Dec.

Authors

Bonnie Yin Ka Lam^{1

2}, Kam Tat Leung¹, Brian Yiu^{1

2}, Lei Zhao^{1

3}, J Matthijs Biesbroek⁴, Lisa Au^{1

2}, Yumi Tang¹, Kai Wang⁵, Yuhua Fan⁶, Jian-Hui Fu⁷, Qun Xu⁸, Haiqing Song⁹, Xiaolin Tian¹⁰, Winnie Chiu Wing Chu¹¹, Jill Abrigo¹¹, Lin Shi^{3

11

12}, Ho Ko^{1

2

13}, Alexander Lau^{1

2}, Marco Duering¹⁴, Adrian Wong^{1

2}, Vincent Chung Tong Mok^{1

2

15}

Affiliations

¹ Department of Medicine and Therapeutics, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, Hong Kong SAR, China.
² Therese Pei Fong Chow Research Center for Prevention of Dementia, Margaret Kam Ling Cheung Research Centre for Management of Parkinsonism, Gerald Choa Neuroscience Centre, The Chinese University of Hong Kong, Shatin, Hong Kong SAR, China.
³ BrainNow Research Institute, Shenzhen, Guangdong Province, China.
⁴ Department of Neurology, Brain Center Rudolf Magnus, University Medical Center Utrecht, Utrecht, Netherlands.
⁵ Department of Neurology, The First Hospital of Anhui Medical University, Hefei, Anhui Province, China.
⁶ Department of Neurology and Stroke Center, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.
⁷ Department of Neurology, Huashan Hospital, Fudan University, Shanghai, China.
⁸ Department of Neurology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.
⁹ Department of Neurology, Xuanwu Hospital of Capital Medical University, Beijing, China.
¹⁰ Department of Neurology, The Second Affiliated Hospital, Tianjin Medical University, Tianjin, China.
¹¹ Department of Imaging and Interventional Radiology, Research Center for Medical Image Computing, The Chinese University of Hong Kong, Shatin, Hong Kong SAR, China.
¹² Department of Imaging and Interventional Radiology, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, Hong Kong SAR, China.
¹³ Li Ka Shing Institute of Health Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong SAR, China.
¹⁴ Institute for Stroke and Dementia Research (ISD), University Hospital, LMU Munich, Munich, Germany.
¹⁵ Shenzhen Research Institute, The Chinese University of Hong Kong, Shatin, Hong Kong SAR, China.

Abstract

Introduction: Only two studies investigated the associations between peak width of skeletonized mean diffusivity (PSMD) and age-related cognitive alterations, whereas none of the studies investigated the association with vascular risk factors.

Methods: We evaluated 801 stroke- and dementia-free elderlies with baseline and 3-year follow-up assessments. Regression analyses were used to assess the association between age-related cognitive functions and PSMD. Simple mediation models were used to study the mediation effect of PSMD between vascular risk factors and age-related cognitive outcomes.

Results: PSMD was negatively associated with processing speed at baseline and negatively associated with processing and memory scores at 3-year follow-up. The association between vascular risk factors and age-related cognition was mediated by PSMD, as well as other diffusion tensor imaging markers.

Discussion: PSMD is preferred over other diffusion tensor imaging markers as it is sensitive to age-related cognitive alterations and calculation is fully automated. PSMD is proposed as a research tool to monitor age-related cognitive alterations.

Keywords: Community subjects; Diffusion tensor imaging; Peak width of skeletonized mean diffusivity; Processing speed; Small vessel disease.