Diabetes mellitus and the risk of Alzheimer's disease: a nationwide population-based study

• Published in: PloS one Vol. 9; no. 1; p. e87095
• Main Authors: Huang, Chin-Chou, Chung, Chia-Min, Leu, Hsin-Bang, Lin, Liang-Yu, Chiu, Chun-Chih, Hsu, Chien-Yi, Chiang, Chia-Hung, Huang, Po-Hsun, Chen, Tzeng-Ji, Lin, Shing-Jong, Chen, Jaw-Wen, Chan, Wan-Leong
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 29.01.2014; Public Library of Science (PLoS)
• Subjects: Advertising executives; Age; Aged; Aging; Alzheimer Disease - epidemiology; Alzheimer Disease - etiology; Alzheimer's disease; Biology; Brain research; Cardiology; Case-Control Studies; Clinical medicine; Combination drug therapy; Confidence intervals; Datasets; Dementia; Diabetes; Diabetes mellitus; Diabetes Mellitus, Type 1 - complications; Diabetes Mellitus, Type 1 - epidemiology; Diabetes Mellitus, Type 2 - complications; Diabetes Mellitus, Type 2 - epidemiology; Diabetics; Disease prevention; Education; Female; Health insurance; Health risks; Hospitals; Hostages; Humans; Hyperlipidemia; Hypertension; Hypoglycemia; Hypoglycemic agents; Incidence; Insulin; Insulin resistance; Kaplan-Meier Estimate; Male; Medical research; Medicine; Middle Aged; National health insurance; Neurodegenerative diseases; Neurology; Online databases; Patients; Pharmacology; Population; Population studies; Population-based studies; Proportional Hazards Models; Regression analysis; Regression models; Risk analysis; Risk factors; Statistical analysis; Stroke; Studies; Therapy; Trends; Urbanization; Veterans; Taiwan
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0087095

Possible association between diabetes mellitus (DM) and Alzheimer's disease (AD) has been controversial. This study used a nationwide population-based dataset to investigate the relationship between DM and subsequent AD incidence. Data were collected from Taiwan's National Health Insurance Research Database, which released a cohort dataset of 1,000,000 randomly sampled people and confirmed it to be representative of the Taiwanese population. We identified 71,433 patients newly diagnosed with diabetes (age 58.74 ± 14.02 years) since January 1997. Using propensity score, we matched them with 71,311 non-diabetic subjects by time of enrollment, age, gender, hypertension, hyperlipidemia, and previous stroke history. All the patients were followed up to December 31, 2007. The endpoint of the study was occurrence of AD. Over a maximum 11 years of follow-up, diabetic patients experienced a higher incidence of AD than non-diabetic subjects (0.48% vs. 0.37%, p<0.001). After Cox proportional hazard regression model analysis, DM (hazard ratio [HR], 1.76; 95% confidence interval [CI], 1.50-2.07, p<0.001), age (HR, 1.11; 95% CI, 1.10-1.12, p<0.001), female gender (HR, 1.24; 95% CI, 1.06-1.46, p=0.008), hypertension (HR, 1.30; 95% CI, 1.07-1.59, p=0.01), previous stroke history (HR, 1.79; 95% CI, 1.28-2.50, p<0.001), and urbanization status (metropolis, HR, 1.32; 95% CI, 1.07-1.63, p=0.009) were independently associated with the increased risk of AD. Neither monotherapy nor combination therapy with oral antidiabetic medications were associated with the risk of AD after adjusting for underlying risk factors and the duration of DM since diagnosis. However, combination therapy with insulin was found to be associated with greater risk of AD (HR, 2.17; 95% CI, 1.04-4.52, p=0.039). Newly diagnosed DM was associated with increased risk of AD. Use of hypoglycemic agents did not ameliorate the risk.