@article{7bf8b39f31324339887e10d0fb25ccdc,
title = "Altered odor-induced brain activity as an early manifestation of cognitive decline in patients with Type 2 diabetes",
abstract = "Type 2 diabetes is reported to be associated with olfactory dysfunction and cognitive decline. However, whether and how olfactory neural circuit abnormalities involve cognitive impairment in diabetes remains uncovered. This study thus aimed to investigate olfactory network alterations and the associations of odor-induced brain activity with cognitive and metabolic parameters in type 2 diabetes. Participants with normal cognition, including 51 patients with type 2 diabetes and 41 control subjects without diabetes, underwent detailed cognitive assessment, olfactory behavior tests, and odor-induced functional MRI measurements. Olfactory brain regions showing significantly different activation between the two groups were selected for functional connectivity analysis. Compared with the control subjects, patients with diabetes demonstrated significantly lower olfactory threshold score, decreased brain activation, and disrupted functional connectivity in the olfactory network. Positive associations of the disrupted functional connectivity with decreased neuropsychology test scores and reduced pancreatic function were observed in patients with diabetes. Notably, the association between pancreatic function and executive function was mediated by olfactory behavior and olfactory functional connectivity. Our results suggested the alteration of olfactory network is present before clinically measurable cognitive decrements in type 2 diabetes, bridging the gap between the central olfactory system and cognitive decline in diabetes.",
author = "Zhou Zhang and Bing Zhang and Xin Wang and Xin Zhang and Yang, {Qing X.} and Zhao Qing and Jiaming Lu and Yan Bi and Dalong Zhu",
note = "Funding Information: Funding. This study was supported by grants from the National Natural Science Foundation of China Grant Award (81770819, 81570736, 81570737, 81370947, 81770819, 81500612, 81400832, 81600637, 81600632, 81703294, 91649116, and 81471643), the National Key Research and Development Program of China (2016YFC1304804 and 2017YFC1309605), Jiangsu Provincial Medical Talent (ZDRCA2016062), the Jiangsu Provincial Key Medical Discipline (ZDXKB2016012), the Key Project of Nanjing Clinical Medical Science, the Key Research and Development Program of Jiangsu Province of China (BE2015604 and BE2016606), the Natural Science Foundation of Jiangsu Province of China (BK20170125), the Jiangsu Provincial Medical Talent (ZDRCA2016062), the Nanjing Science and Technology Development Project (201605019), the Medical Scientific Research Foundation of Jiangsu Province of China (Q2017006), and the Fundamental Research Funds for the Central Universities (021414380142 and 021414380317). Duality of Interest. No potential conflicts of interest relevant to this article were reported. Author Contributions. Z.Z. contributed to data collection and statistical analyses and wrote the manuscript. B.Z. designed the protocol and reviewed and edited the manuscript. X.W. contributed to data collection and MRI analysis and wrote the manuscript. X.Z. designed the protocol and contributed to MRI analysis. Q.X.Y. designed the protocol and reviewed and edited the manuscript. Z.Q. and J.L. contributed to MRI analysis. Y.B. and D.Z. designed the study and oversaw all clinical aspects of study conduct and manuscript preparation. Y.B. and D.Z. are the guarantors of this work and, as such, had full access to all of the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis. Prior Presentation. This study was presented in oral form at the 53rd Annual Meeting of the European Association for the Study of Diabetes, Lisbon, Portugal, 11– 15 September 2017. Publisher Copyright: {\textcopyright} 2018 by the American Diabetes Association.",
year = "2018",
month = may,
day = "1",
doi = "10.2337/db17-1274",
language = "English (US)",
volume = "67",
pages = "994--1006",
journal = "Diabetes",
issn = "0012-1797",
publisher = "American Diabetes Association Inc.",
number = "5",
}
