Longitudinal Associations of Newly Diagnosed Prediabetes and Diabetes with Cognitive Function among Chinese Adults Aged 45 Years and Older

Abstract

With population aging, diabetes mellitus and cognitive function decline are common health problems among older adults worldwide. This longitudinal study is aimed at estimating the longitudinal associations of newly diagnosed prediabetes and diabetes status with cognitive function among Chinese adults aged 45 years and older and evaluating the clinical risk factors associated with cognitive function. Data were obtained from the China Health and Retirement Longitudinal Study (CHARLS). A total of 8716 participants meeting the inclusion criteria were enrolled between 2011 and 2012 at baseline, and 6125 participants completed the follow-up survey in 2018. Cognitive function, newly diagnosed diabetic status, depression, body mass index, and clinical and biochemical measurements were collected. At baseline, the mean age of the participants was 58.93 (SD: 9.76) years, 3987 (45.7%) were males, 1802 (20.7%) participants were newly diagnosed with prediabetes, and 935 (10.7%) were diabetes patients. After adjusting for control variables, diabetes was a significant risk factor for subsequent cognitive decline (unstandardized β estimate = − 0.50 , 95 % CI = − 0.98 ~ − 0.02 ). Subgroup analyses found that the association of diabetes with cognitive decline was significant in females. Stratification analyses found that among prediabetes patients, triglyceride concentrations were negatively associated with cognitive function; among diabetes patients, high-sensitivity C-reactive protein was significantly associated with cognitive decline. The newly diagnosed diabetes status at baseline was associated with subsequent cognitive decline among middle-aged and elderly Chinese, especially in females. The management of triglycerides through lifestyle modification for prediabetes and specific adjunctive anti-inflammatory therapy for diabetes might benefit cognitive performance.

Cognition and BDNF levels in prediabetes and diabetes: A mediation analysis of a cross-sectional study

“…One systematic review (28) suggest there is insufficient evidence to support a connection between prediabetes and cognitive impairment, while another meta-analysis reported that there was moderate-to-high-quality evidence of a positive association between prediabetes and dementia (29). An 8-year longitudinal study also found no significant association between baseline prediabetes status and later cognitive function (30). Further research with larger sample sizes is needed to better understand cognitive impairment in prediabetes.…”

Association of prediabetes progression and regression with cognitive decline: Findings from the CHARLS

“…Covariates were selected based on previous studies for their potential association with diabetes and cognitive function 16,17 . They included age (year), sex, marital status (married or cohabitated, widowed, other status), physical activity (based on short form of the International Physical Activity Questionnaire, 18 only half participants were randomly chosen to answer these questions), level of education (no formal education, middle school education and high school education and above), living in rural or urban area, current smoking status (still have the habit of smoking vs. have quitted smoking or non‐smokers), current alcohol drinker (yes/no, drink any alcoholic beverages in the past year), body mass index (BMI, kg/m 2 ), dyslipidaemia (total/high density lipoprotein (HDL) cholesterol ratio), high‐sensitivity C‐reactive protein (CRP), depression (defined as the 10‐item Center for Epidemiological Studies Depression Scale of 10 or greater, range 0–30) 19 and self reported hypertension, heart disease and stroke by asking ‘Have you been diagnosed with [conditions listed below, read one by one] by a doctor?’…”

“…Covariates were selected based on previous studies for their potential association with diabetes and cognitive function. 16,17 They included age (year), sex, marital status (married or cohabitated, widowed, other status), physical…”