Correlation between the levels of serum lipids and the onset of disease in patients with Alzheimer disease: 1:1 paired observation

Aim: To study the association between the changes of lipids metabolism and the onset of disease. Methods: All patients with Alzheimer disease were selected from the Department of Neurology, First Hospital of Xi' an Jiaotong University from 1997 to 2001 diagnosed by the task of Alzheimer disease epidemiological survey in Xi' an region. The 27 patients (> 55 years of age) with final diagnosis of Alzheimer disease from epidemiological study and had been followed-up for 2 years were detected. Matched controls were the health elder people strictly according to 1:1 pair-matching, living in the same area with the same sex and education, less than 3 years of age difference. The difference of serum lipids between patients with Alzheimer disease and matched controls were observed. All factors were analyzed by using logistic factor analysis, rank correlation analysis and linear correlation analysis to screen the dangerous factors of Alzheimer disease. Results: According to intention-to-treat analysis, all 27 patients and 27 healthy persons were involved in the result analysis. 1 There was no significant difference between Alzheimer disease patients and the matched controls in serum total cholesterol, free cholesterol, triglyceride, high density lipoprotein cholesterol, low density lipoprotein cholesterol and apolipoprotein B. But the level of serum apolipoprotein A in Alzheimer disease patients [(1.3 ± 0.2) mmol/L] was significantly higher as compared with that in the matched controls (1.2 ± 0.2) mmol/L] (t = 2.74, P < 0.05). 2 Serum apolipoprotein A was a risk factor for Alzheimer disease; rank correlation analysis indicated serum apolipoprotein A had the positive correlation with Alzheimer disease (r_s = 0.357, P = 0.008); linear correlation indicated between the level of serum apolipoprotein A and serum total cholesterol (r_s = 0.441, P < 0.05), and high density lipoprotein cholesterol (r_s = 0.553, P < 0.05); linear regression correlation indicated between the level of serum apolipoprotein A and serum total cholesterol, and the linear regression equation was Y= -2.039 1 + 0.737 X. Conclusion: The level of serum apolipoprotein A in patients with Alzheimer disease is obviously higher as compared with that in control group, it increases along with the increasing severity of Alzheimer disease. The result indicates that serum apolipoprotein A may be one of the dangerous factors for Alzheimer disease.