The mechanism underlying fluoride-induced low-renin hypertension is related to an imbalance in the circulatory and local renin-angiotensin systems.

The renin-angiotensin system (RAS) is an important fluid regulation system in the body, and excessive activation of the circulatory or local RAS can increase blood pressure (BP). Excess fluoride can increase BP, although the underlying mechanism related to activation of the RAS remains unclear. Thus, the aim of this study was to elucidate the role of the RAS in fluoride-induced hypertension. Markers of the circulating and local RASs related to pathological changes to the kidneys, myocardium, and aorta were measured. Fluoride reduced serum levels of renin, angiotensin II (Ang II), and angiotensin (1-7) [Ang (1-7)], and dysregulated plasma levels of aldosterone and potassium levels. Excess fluoride can damage the kidneys, myocardium, and aorta, overactivate the renal angiotensin converting enzyme (ACE)-Ang II-angiotensin type 1 receptor axis, and inhibit activation of the ACE2-Ang (1-7)-Mas axis, leading to dysregulation of alpha epithelial sodium channels and significantly increased expression of Ang II in the myocardium and aorta. Hence, excess fluoride can cause low-renin hypertension via an imbalance between the circulatory and local RASs.

Environment and chronic disease in rural areas of Heilongjiang, China (ECDRAHC).

PURPOSE: Environmental factors such as long-term exposure to cold can increase the risk of chronic diseases. However, few studies have focused on the impact of environmental factors and lifestyle changes on chronic diseases. To fully explore the association between exposure to environmental factors and the prevalent risk of various chronic diseases, we conducted a large cohort study (Environment and Chronic Disease in Rural Areas of Heilongjiang, China (ECDRAHC)). The ECDRAHC collected detailed questionnaire data covering 10 sections, physical measurements and blood and urine samples. In this study, we describe the design and implementation of the cohort study and present the findings for the first 10 000 participants. PARTICIPANTS: The ECDRAHC study was carried out in rural areas where the annual average temperature is 2.9°C, and aimed to recruit 40 000 participants who are long-term residents aged 35-74 years. The participants will be followed up every 5 years. Currently, ECDRAHC has reached 26.7% (n=10 694) of the targeted population. FINDINGS TO DATE: A total of 10 694 adults aged 35-74 years were recruited, including 61.7% women. The prevalence of current smokers was 46.8% in men and 35.4% in women. The mean blood pressure was 140.2/89.9 mm Hg and 135.7/85.0 mm Hg in men and women, respectively. The mean body mass index was 24.74 kg/m2 in men and 24.65 kg/m2 in women, with >7.3% being obese (>30 kg/m2). The main non-communicable diseases found in phase 1 were hypertension, diabetes, hypertriglyceridaemia and metabolic syndrome, with a higher prevalence of 51.0%, 21.6%, 46.8% and 42.6%, respectively. FUTURE PLANS: We plan to complete the follow-up for the first phase of the ECDRAHC in 2024. The second and third phase of the cohort will be carried out steadily, as planned. This cohort will be used to investigate the relationship between environmental factors, lifestyle, and genetic and common chronic diseases.

Evaluation of Risk Factors for Chronic Obstructive Pulmonary Disease in the Middle-Aged and Elderly Rural Population of Northeast China Using Logistic Regression and Principal Component Analysis.

Purpose: To investigate the environmental, immune, and inflammatory factors associated with chronic obstructive pulmonary disease (COPD) in middle-aged and older Chinese individuals. Patients and Methods: A community-based case-control study was conducted among 471 patients with COPD and 485 controls. The information on COPD of the participants was collected through face-to-face interviews, and serum samples were measured at the laboratory. The main risk factors for COPD were analyzed using principal component analysis (PCA) and logistic regression. Results: Nine hundred and fifty-six respondents were included in the analysis. The results of the PCA-logistic regression analysis showed significant differences in the environmental factors, medical history, and serum C-reactive protein (CRP) levels between patients and controls. COPD was markedly more usual in those with smoking index >200 (OR, 1.42; 95% CI, 1.28-1.57); exposure to outdoor straw burning (OR, 1.64; 95% CI, 1.47-1.83); use of coal, wood, and straw indoors (OR, 2.31; 95% CI, 1.92-2.78); history of respiratory disease and coronary heart disease (OR, 3.58; 95% CI, 3.12-4.10), congestive heart failure (OR, 1.23; 95% CI, 1.09-1.38), and cerebrovascular disease (OR, 1.15; 95% CI,1.02-1.31); and higher serum level of CRP (OR, 1.20; 95% CI, 1.11-1.30). Compared to the logistic regression analysis, PCA logistic regression analysis identified more important risk factors for COPD. Conclusion: PCA-logistic regression analysis was first utilized to explore the influencing factors among rural residents in Northeast China Environmental aged 40 years and above, it was found that environmental factors, medical history, and serum CRP levels mainly affected the prevalence of COPD.