Serum ferritin contributes to racial or geographic disparities in metabolic syndrome in Taiwan.

OBJECTIVES: Asians and Pacific Islanders have higher circulating serum ferritin (SF) compared with Caucasians but the clinical significance of this is unclear. There is a higher prevalence of metabolic syndrome (MetS) in Taiwanese Indigenous than Han Chinese. Genetically, Indigenous are related to Austronesians and account for 2 % of Taiwan's population. We tested the hypothesis that accumulation of Fe in the body contributes to the ethnic/racial disparities in MetS in Taiwan. DESIGN: A population-based, cross-sectional study. SETTING: National Nutrition and Health Survey in Taiwan and Penghu Island. SUBJECTS: A total of 2638 healthy adults aged ≥19 years. Three ethnic groups were included. RESULTS: Han Chinese and Indigenous people had comparable levels of SF. Austronesia origin was independently associated with MetS (OR = 2·61, 95 % CI 2·02, 3·36). After multiple adjustments, the odds for MetS (OR = 2·49, 95 % CI 1·15, 5·28) was significantly higher among Indigenous people in the highest SF tertile compared with those in the lowest tertile. Hakka and Penghu Islanders yielded the lowest risks (OR = 1·08, 95 % CI 0·44, 2·65 and OR = 1·21, 95 % CI 0·52, 2·78, respectively). Indigenous people in the highest SF tertile had increased risk for abnormal levels of fasting glucose (OR = 2·34, 95 % CI 1·27, 4·29), TAG (OR = 1·94, 95 % CI 1·11, 3·39) and HDL-cholesterol (OR = 2·10, 95 % CI 1·18, 3·73) than those in the lowest SF tertile. CONCLUSIONS: Our results raise the possibility that ethnic/racial differences in body Fe store susceptibility may contribute to racial and geographic disparities in MetS.

Increased risk of stroke among patients with ankylosing spondylitis: a population-based matched-cohort study.

Ankylosing spondylitis (AS) is a chronic inflammatory rheumatic disease. Although two prior studies detected increased prevalence ratios of cerebrovascular disease among AS patients, the results of the two studies investigating AS and stroke are in conflict. Therefore, the present cohort study set out to estimate the risk of subsequent stroke in AS patients compared with matched controls using a population-based dataset in Taiwan. This investigation analyzed administrative claims data sourced from the Taiwan National Health Insurance Database. Our study consisted of a study cohort comprising 1,479 AS patients and a comparison cohort of 5,916 subjects without AS. Cox proportional hazards regressions were performed to estimate the risk of subsequent stroke during the follow-up period. We also conducted additional analyses investigating the risk of subsequent stroke by gender and pharmaceutical prescription. After adjusting for chronic lower respiratory diseases, type 2 diabetes mellitus, hypertension, hyperlipidemia, renal disease, coronary heart disease, atrial fibrillation, income, and urbanization, compared with comparison patients, the hazard ratio for subsequent stroke among patients with AS was 2.3 (95 % CI 1.9-2.8). We also stratified our results by both gender and pharmaceutical prescription, but did not find a statistically significant difference for the risk of subsequent stroke either between men and women, or between AS patients taking various pharmaceutical regimens and the overall AS population. This is the first study to report an increased hazard ratio for subsequent stroke among AS patients when compared with matched comparison patients without AS.

Serum ferritin and risk of the metabolic syndrome: a population-based study.

Ferritin concentrations in circulation reflect iron stores in healthy individuals. However, elevated serum ferritin (SF) concentrations have recently been implicated in the pathogenesis of the metabolic syndrome (MetS). We aim to investigate factors associated with elevated SF and to evaluate the association between SF and risk of MetS in Taiwanese adults. Data was collected from 2654 healthy individuals aged >=19 years old, who participated in the Nutrition and Health Survey in Taiwan (NAHSIT Adults 2005-2008). Mean concentrations of SF were 173±282 ng/mL (men 229±349 ng/mL and women 119±180 ng/mL). Prevalence proportion of MetS was 34.6% (men 43.1% and women 26.5%). Prevalence proportion of iron overload was 18.6% (men 21.5% and women 15.8%) and iron deficiency anemia was 5.2% (2.0% for men and 8.3% for women). Individuals with the highest SF tertile (T3) were more likely to consume higher amount of animal protein (p=0.001), betel nuts (p=0.004), and lower amounts of carbohydrates (p<0.0001), compared with the lowest SF group (T1). After adjustments, individuals with the highest SF tertile were associated with risk of MetS compared with those with the lowest (OR=1.724, 95% CI: 1.21-2.45). Serum ferritin concentrations showed a gradient relationship with individual components of MetS (all p<0.0001). Individuals with the highest SF tertile were significantly associated with fasting serum glucose (OR=2.16, 95% CI: 1.75-2.65) and serum triglyceride (OR=2.58, 95% CI: 1.07-3.22) than those with the lowest. In conclusions, our results highlight the crucial role of serum ferritin in the pathogenesis of the MetS in healthy Taiwanese adults.

Adults with late stage 3 chronic kidney disease are at high risk for prevalent silent brain infarction: a population-based study.

BACKGROUND AND PURPOSE: The close relationship between stroke and chronic kidney disease (CKD) has been well-documented. However, few studies have focused on silent brain infarction (SBI) in CKD. We investigated the prevalence of SBI in different stages of CKD. METHODS: We included 1312 participants aged 30 to 93 years who came from either a random sample of residents or from a group of physically examined subjects in the same community. Basic information, clinical evaluations, laboratory tests, and MRI images were assessed. Subjects were divided into groups 1, 2, 3a, and 3b, corresponding to the estimated glomerular filtration rate (eGFR) levels of ≥ 90.0, 60.0 to 89.9, 45.0 to 59.9, and 30.0 to 44.9 mL/min/1.73 m². RESULTS: The crude prevalence was 4.7%: 2.6% (20 of 759 subjects) in group 1; 6.3% (32 of 506) in group 2; 12.9% (4 of 31) in group 3a; and 37.5% (6 of 16) in group 3b (P<0.001). Additionally, SBI also correlated with age, male sex, hypertension, diabetes, moderate carotid plaque, higher blood pressures, obesity, and levels of triglyceride, high-density lipoprotein cholesterol, high-sensitivity C-reactive protein, and uric acid (all P<0.05). The effects for SBI risk in each eGFR group versus group 1 did not increase except for group 3b (OR, 9.34; P<0.001). CONCLUSIONS: A close association exists between SBI and eGFR. We have found a significant increase in prevalence of SBI when eGFR is between 30.0 and 44.9 mL/min/1.73 m². Adults with late stage 3 CKD are at high risk for prevalent SBI.