Association of β-amyloid 40 and 42 With Prediabetes
Condition: PreDiabetes
MeSH terms: Prediabetic State; Glucose Intolerance; Amyloidosis
Study type: Observational

Summary: 
      Background: Previous epidemiological and animal studies have suggested a strong relationship
      between prediabetes and Alzheimer's disease. Recently, we demonstrated that plasma β-amyloid
      (Aβ), a potential biomarker for Alzheimer's disease, was elevated in individuals with type 2
      diabetes. However, few studies have investigated the associations of plasma Aβ40 and Aβ42
      concentrations with prediabetes.

      Objective: we aimed to investigate the associations of plasma Aβ40 and Aβ42 concentrations
      with risk of prediabetes in two independent studies.

      Design: We performed a case-control study and a nested case-control study within a
      prospective cohort study. In the case-control study, we included 571 newly diagnosed
      individuals with prediabetes and 571 control participants. Prediabetes individuals were
      consecutively recruited from subjects who attended the outpatient clinics of Department of
      Endocrinology at Tongji Medical College Hospital from 2012 to 2015. Concomitantly, we
      recruited healthy controls from a general population undergoing a routine health checkup in
      the same hospital. One healthy control was selected at random for each prediabetes
      individuals according to age (±3 years) and sex. The inclusion criteria of participants were
      as follows: age ≥30 and ≤80 years, BMI <40 kg/m2, no history of prediabetes and diabetes
      mellitus, no history of receiving pharmacological treatment for hyperlipidemia, nor any
      clinically systemic disease, any acute illness, and chronic inflammatory or any infective
      disease. An independent nested case-control study was conducted within an ongoing cohort
      study, namely the Tongji-Ezhou cohort. Briefly, 5533 participants, including 3101 retired
      employees and 2432 working employees, were enrolled from Echeng Stell and received healthcare
      for a baseline investigation between 2013 and 2015. The first follow-up for all participants
      was finished by mid-2020. Considering the low incidence of prediabetes among young working
      employees, we performed the nested case-control study among retired employees. During the
      follow-up, 119 new-onset prediabetes cases were diagnosed within the retired employees
      according to fasting plasma glucose. We randomly selected the control participants who
      matched 2:1 to the cases by age (±3 years) and sex from the retired employees with normal
      fasting plasma glucose. The inclusion criteria were the same as the case-control study; 2
      new-onset prediabetes cases aged >80 years were excluded. Additionally, 17 cases without
      enough plasma were excluded. Finally, 100 individuals with new-onset prediabetes and 200
      well-matched control participants were included for the analysis of the nested case-control
      study. These two studies were approved by the Ethics and Human Subject Committee of Tongji
      Medical College. All enrolled participants in the two studies were of Chinese Han ethnicity
      and provided informed written consent. Plasma Aβ40 and Aβ42 concentrations were
      simultaneously measured by validated assay platforms from Meso Scale Discovery (MSD;
      Rockville, MD, USA).
    


Intervention name(s): Plasma β-amyloid 40 and 42 concentration
Intervention type(s): Other
Intervention description(s): Plasma β-amyloid 40 and 42 concentrations were simultaneously measured by validated assay platforms from Meso Scale Discovery (MSD; Rockville, MD, USA).
Observational model: Case-Control
Time perspective: Retrospective
Sampling method: Probability Sample
Study population: 
        All the participants enrolled were of Chinese Han ethnicity. They gave informed written
        consent to the study and did not take any medication known to affect glucose tolerance or
        insulin secretion before participation.
      
Keywords: β-amyloid 40; β-amyloid 42; prediabetes