Risk Factors Of Post-stroke Apathy And A Diffusion Tensor Imaging Based White Matter Network Study

Back ground and purposePost-stroke apathy is one of the important neuropsychiatric symptom with highprevalence, however, the risk factors and the structural basis of post-stroke apathyremains unclear. The purpose of this study was to explore the risk factors and thestructural basis for the presence of post-stroke apathy.Materials and methods (1) Eighty-five patients with ischemic stroke onset within14days wererecruited from our hospital. Patients were grouped into two groups: apathy andnon-apathy group. Demographic data (age, gender, education year), basic medicalhistory (hypertension, diabetes mellitus, vascular disease), personal history (smoking,drinking), and baseline characteristics (blood pressure, heart rate, glycosylatedhemoglobin, triglyceride, total cholesterol, high-density lipoprotein, low densitylipoprotein) were recorded. The NIHSS score, lesion location, cognitive function(MMSE, MOCA) and depression (HAMD) were assessed. All the factors werestatistical analyzed between apathy and non-apathy groups. Multiple logisticregression was then employed to explore the independence risk factors of post-strokeapathy.(2) Fifty-six patients who were checked by DTI of the85patients wereenrolled. Demographic and the clinical data were the same as part one. DTI-basedwhite matter structural network was employed and analyzed using graph theory. Thetopological properties of whole brain network and node were firstly calculated.Basing on the probable apathy-related nodes, the whole brain network weresegmented into three parts, thus the apathy-related network, the apathy-unrelatednetwork and the between connections. All the topological properties of the networkswere firstly statistically analyzed between groups, and then were put into multiplelogistic regression equation.Results(1) Twenty-eight (32.9%) of the85patients were diagnosed as apathy. Age,education year, cerebral vascular disease, cognitive function, depression, lesions inthe frontal lobe and basal ganglia were found associated with apathy, while thedecrease of the MMSE score (OR:0.76,95%CI:0.65-0.88, P<0.01) and a history ofcerebral vascular disease (OR:10.27,95%CI:2.61-40.44, P<0.01) could beregarded as independence risk factors of post-stroke apathy.(2) Localefficiency(r=-0.39, P<0.01) and global efficiency (r=-0.44, P<0.01) of the wholebrain network were related to the AES-C scores, and the efficiencies of34nodeswere found either related to AES-C scores or decreased in the apathy group. The local efficiency (r=-0.28，P=0.04) and global efficiency (r=-0.59，P<0.01) of theapathy-related sub-network constructed by the34nodes were both decreased in theapathy group, and they are both related to the AES-C scores (local efficiency:r=-0.28，P=0.04, global efficiency: r=-0.59，P<0.01) as well, but the apathy-unrelatednetwork were not related to apathy. Moreover, the strength of the betweenconnections were both decreased in the apathy group (P<0.01) and related to theAES-C scores (r=-0.52，P<0.01). In the multiple logistic regression, the decrease ofthe apathy-related network’s global efficiency (OR：0.00,95%CI:0.00-0.07, P=0.01)and history of cerebral vascular disease (OR:6.41,95%CI:1.32-31.15, P=0.02)were independent risk factors of post-stroke apathy.Conclusion(1) Post-stroke apathy may relate to age, education year, a history of cerebralvascular disease, cognitive function, depression, lesions in the frontal lobe and basalganglia, while the decrease of MMSE score and a history of cerebral vasculardisease can be regarded as independent risk factors of post-stroke apathy.(2) Apathyis associated with the damage of white matter integrity, the structural basis iscomplex, which may be attributed to the frontal—subcortical circuits and part of thelimbic system and parietal lobe. The apathy-related network we constructed can beregarded as an independent risk factor of post-stroke apathy, and may somewhatdescribe the structural basis of post-stroke apathy. The two parts of study maycontribute to the study of post-stroke apathy, but cannot be used in a clinical settingbefore more studies.