A Meta-Analysis of C-Reactive Protein in Patients With Alzheimer’s Disease

Inflammation may be associated with Alzheimer’s disease (AD). This meta-analysis aimed to compare the level of C-reactive protein (CRP) in patients having AD to healthy controls. A total of 10 cross-sectional studies (n = 2093) were identified from PubMed and EMBASE after systematic searching and evaluation. The combined standardized mean difference (SMD) of CRP level between the disease and control group was analyzed. In the meta-analysis, there was no significant difference in serum between the CRP level of patients with AD and that of healthy controls (SMD: −0.400, 95% confidence interval [CI]: −0.827 to 0.027, P = .066). However, when we stratified the studies by Mini-Mental State Examination (MMSE) scores, the level of CRP in the mild and moderate dementia subgroup (MMSE ≥ 10) was significantly lower than that in the control group (SMD: −0.582, 95% CI: −0.957 to −0.208, P = .002). Therefore, the diagnostic value of CRP for mild and moderate AD may be useful in clinical practice.

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