Infection is one of the most important complications of acute stroke, and it is an independent risk factor for resulting in stroke worsening. Growing evidence has indicated that acute stroke patients suffer an impaired peripheral immune response, i.e. stroke-induced immunodepression system (SIDS). SIDS is characterized by the rapid and sustained cellular immunodepression after acute stroke, which is mainly presented as wide apoptosis and dysfunction of lymphocyte. Multiple reasons activate the sympathetic nervous system, and thus cause SIDS. SIDS weakens the effective defense against the invasion of pathogens in the human body, resulting in the increased infection and mortality rate. However, SIDS also has protective effect on the human body. It can prevent the excessive inflammatory response in the injured brain tissue. A better understanding of the complex relationships between the central nervous system and the immune system are promising to provide more effective treatment methods for patients with acute stroke.

Objective To explore the independent risk factors related to acute post-stroke pneumonia.Methods A total of 545 inpatients with acute stroke in Shanghai First People's Hospital Affiliated to Shanghai Jiaotong University and East Hospital Affiliated to Tongji University during July 1,2009 to June 30,2011 were enrolled.Single-factor analysis was performed to identify the risk factors of acute post-stroke pneumonia. According to the results of single-factor analysis and relevant professional knowledge,fitting multi-factor non-conditional Logistic regression model,adjusting the relevant confounded factors,the independent risk factors were analyzed.Results The incidence of acute post-stroke pneumonia was 11.0％ (60/545).The independent risk factors of acute post-stroke pneumonia were:age ≥ 80 year ( OR =6.024,95％ CI:1.923 - 18.868,P =0.002 ),hemorrhagic stroke ( OR =3.546,95％ CI:1.266 -9.901,P =0.016),stay in bed ( OR =4.295,95％ CI:1.642 - 11.233,P =0.003 ),baseline Glasgow coma scale ≤8 ( OR =5.127,95％ CI:1.377 - 19.090,P =0.015 ),baseline Barthel index ＜50 ( OR =8.403,95％ CI:1.468 -47.619,P =0.017 ),malnutrition ( OR =10.625,95％ CI:3.260 -34.631,P =0.000 ),baseline fasting plasma glucose ≥ 7.0 mmol/L ( OR =10.000,95％ CI:3.115 -32.258,P =0.000); and early rehabilitation was the protective factor (OR =0.159,95％ CI:0.055 -0.466,P =0.001 ).Conclusions The incidence of acute post-stroke pneumonia is high,and it is relatedwith many independent risk factors.Comprehensive interventions may contribute to early identify and prevent acute post-stroke pneumonia.

Objective To explore the relationship between orthostatic hypotension (OH) and cognition impairment (CI) in the elderly.Methods Forty-four OH patients who visited our hospital due to dizziness,vertigo and fatigue during January 2009 to December 2011 were enrolled in the exposed group (OH group),and 88 healthy elderly paired in 1:2 were enrolled in the control group (NOH group).The socio-demographic data and cognition-related factors between the two groups were collected at baseline;cognitive function was assessed using mini-mental state examination (MMSE) 4 years after baseline of the present study.Results The overall incidence of CI was 14.0％ among the 114 subjects who completed the follow-up assessment.Significant difference in CI incidence was noted between OH group (23.7％) and NOH group (9.2％,x2=4.399,P=0.036).The analysis by age showed that there was no significant difference in CI incidence between the OH group (15.4％) and NOH group (9.1％) among the elderly younger than 70 years;the CI incidence in OH group (41.7％) was significantly higher than that in NOH group (9.3％) among the elderly older than 70 years (x2=5.935,P=0.016).Conclusion OH is a risk factor of CI among the elderly older than 70 years.