Associations SELE gene haplotype variant and hypertension in Mongolian and Han populations

Prevalence of and risk factors for refractive error: a cross-sectional study in Han and Mongolian adults aged 40-80 years in Inner Mongolia, China

OBJECTIVES

To assess the prevalence of and risk factors for refractive error (RE) in Han and Mongolian adults aged 40-80 years in Inner Mongolia in China and to identify ethnic differences in RE between these populations.

METHODS

Our cross-sectional study is part of the China National Health Survey (CNHS). The age-adjusted prevalence of RE in Han and Mongolian adults aged 40-80 in Inner Mongolia were compared. A multivariable logistic regression model was used to identify risk factors.

RESULTS

Among 2090 people, the age-adjusted prevalence of myopia (SE < -0.5D), hyperopia (SE > 0.5D), high myopia (SE < -6.0D) and astigmatism (cylinder ≥ 0.5D) were 29.4% (95% confidence interval (CI), 27.4-31.3%), 28.4% (95% CI, 26.4-30.5%), 3.6% (95% CI, 2.8-4.4%) and 65.9% (95% CI, 63.9-67.9%), respectively. The age-adjusted prevalence of myopia in the Han population was higher than that in the Mongolian population (31.8% vs. 23.0%, p < 0.001), but the prevalence of hyperopia was lower (25.8% vs. 35.3%, p = 0.002). In the multivariable logistic regression, ethnicity was associated with myopia (p = 0.001) and hyperopia (p = 0.001). Myopia was also associated with age, time spent in rural areas (p < 0.001) and middle/high school and undergraduate/graduate education levels (p = 0.027 and p < 0.001, respectively, compared with lower education levels). Additionally, age, height (p = 0.015) and pterygium (p = 0.014) were associated with hyperopia.

CONCLUSIONS

Ethnicity is closely related to RE in Inner Mongolia in mainland China. Our study investigates differences in prevalence of and risk factors for RE between the Han and Mongolian populations, which could not be explained by differences in the risk factors investigated in this study.

Hypertension and physical activity in middle-aged and older adults in China

There are few studies examining the association between levels of physical activity and hypertension in middle-aged and older adults in China. Data were drawn from the Chinese Health and Retirement Longitudinal Study (using four-stage stratified probability-proportional-to-size sampling), involving 7113 individuals aged 45 years and older from 28 provinces of China. Hypertension was defined as a systolic BP ≥ 130 mm Hg, or diastolic BP ≥ 80 mm Hg, or self-reported use of anti-hypertensive medications. The awareness, treatment, and control among hypertensive participants were 53.12%, 43.37%, and 10.03%, respectively. The prevalence of hypertension was 56.12% among all the participants, higher in main city zones (58.68%) than villages (55.52%) and other areas (55.78%, p < 0.0001). Participants who were overweight (BMI ≥ 24: AOR 4.08, 95% CI 3.21-5.20, P < 0.0001; BMI ≥ 28: 10.03, 7.56-13.31, P < 0.0001), and drinking more than once a month (1.28, 1.12-1.46, P < 0.0001) were more likely to have hypertension. The decision tree model was established to analyze the importance of different levels of physical activity on hypertension prevention. Participants who usually participated in moderate-to-vigorous activity for more than 10 minutes (vigorous: 0.82, 0.73-0.91, P = 0.0004; moderate: 0.83, 0.75-0.92, P = 0.0006) were less likely to have hypertension. The results of the decision tree showed that the vigorous physical activity seemed to be more important than moderate and light activity to induce beneficial effects on prevention of hypertension. The strength of our study is in using the decision tree to clearly rank the importance of those key factors affecting hypertension.

Gene-Centric Analysis of Preeclampsia Identifies Maternal Association at PLEKHG1

The genetic susceptibility to preeclampsia, a pregnancy-specific complication with significant maternal and fetal morbidity, has been poorly characterized. To identify maternal genes associated with preeclampsia risk, we assembled 498 cases and 1864 controls of European ancestry from preeclampsia case-control collections in 5 different US sites (with additional matched population controls), genotyped samples on a cardiovascular gene-centric array composed of variants from ≈2000 genes selected based on prior genetic studies of cardiovascular and metabolic diseases and performed case-control genetic association analysis on 27 429 variants passing quality control. In silico replication testing of 9 lead signals with P<10-4 was performed in independent European samples from the SOPHIA (Study of Pregnancy Hypertension in Iowa) and Inova cohorts (212 cases, 456 controls). Multiethnic assessment of lead signals was then performed in samples of black (26 cases, 136 controls), Hispanic (132 cases, 468 controls), and East Asian (9 cases, 80 controls) ancestry. Multiethnic meta-analysis (877 cases, 3004 controls) revealed a study-wide statistically significant association of the rs9478812 variant in the pleiotropic PLEKHG1 gene (odds ratio, 1.40 [1.23-1.60]; Pmeta=5.90×10-7). The rs9478812 effect was even stronger in the subset of European cases with known early-onset preeclampsia (236 cases diagnosed <37 weeks, 1864 controls; odds ratio, 1.59 [1.27-1.98]; P=4.01×10-5). PLEKHG1 variants have previously been implicated in genome-wide association studies of blood pressure, body weight, and neurological disorders. Although larger studies are required to further define maternal preeclampsia heritability, this study identifies a novel maternal risk locus for further investigation.