title: Circulating immune complexes in sera from patients with Alzheimer's disease and subjects with age-associated memory impairment.
abstract: Before, we reported a higher frequency of circulating immune complexes (CIC) in the sera from institutionalized Alzheimer's disease (AD), multi-infarct dementia and Down's syndrome patients than from age-matched controls. In this study, we tested the presence of CIC in the sera from an extended series of hospitalized AD patients, AD patients living in the community, from age-associated memory impairment (AAMI) subjects as well as from nursing home and community controls. We used two methods to measure CIC, C1q binding Elisa (C1qB-Elisa) and conglutinin binding (KgB-Elisa). The AD patients showed the highest frequency of positive findings and differed from the controls in KgB (42% vs. 17%) (Chi-square, p = 0.01) and C1qB (30% vs. 11%) (p < 0.05). In severe AD, 14/19 patients were KgB positive and 11/19 were C1qB positive and differed from controls. The frequency of CIC for the patients with moderate or mild dementia, the AAMI subjects and controls was similar. In the multivariate linear regression analysis, high CIC values of the AD patients significantly associated with a long disease duration and a history of recurrent urinary infections but not with age, sex, hospitalization, or the Mini-Mental Status score. We conclude that AD patients with severe dementia frequently show CIC but those with mild or moderate disease do not. The CIC relate to a long disease duration and a history of recurrent urinary infections.
authors.affiliation: Department of Neurology, University of Kuopio, Finland.
authors.forename: H
authors.initials: H
authors.lastname: Soininen
authors.forename: O
authors.initials: O
authors.lastname: Heinonen
authors.forename: M
authors.initials: M
authors.lastname: Hallikainen
authors.forename: T
authors.initials: T
authors.lastname: Hänninen
authors.forename: K
authors.initials: K
authors.lastname: Koivisto
authors.forename: S
authors.initials: S
authors.lastname: Syrjänen
authors.forename: S
authors.initials: S
authors.lastname: Talasniemi
authors.forename: P J
authors.initials: PJ
authors.lastname: Riekkinen
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000276:immunology; D000544:Alzheimer Disease / Q000276:immunology* / Q000473:pathology / Q000523:psychology; D000906:Antibodies / Q000032:analysis; D000936:Antigen-Antibody Complex / Q000032:analysis*; D037222:Collectins; D015922:Complement C1q / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007164:Immunosorbents; D008297:Male; D008569:Memory Disorders / Q000276:immunology* / Q000473:pathology / Q000523:psychology; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales; D012008:Recurrence; D012712:Serum Globulins / Q000276:immunology; D014552:Urinary Tract Infections / Q000276:immunology
chemical_list: D000906:Antibodies; D000936:Antigen-Antibody Complex; D037222:Collectins; D007164:Immunosorbents; D012712:Serum Globulins; C024014:conglutinin; D015922:Complement C1q