Clinical implications of local renin-angiotensin-aldosterone systems

Relationship between lipid levels, TyG, TyG-BMI index and hypertension in Tibetan population in Tibet, China based on restricted cubic spline model

BACKGROUND

The prevalence of hypertension among the Tibetan population in Tibet is higher than in other regions of China, and there is a lack of unified epidemiological surveys. This study aims to conduct a standardized epidemiological investigation to assess the current status of hypertension among the Tibetan population, as well as to explore the dose-response relationship between cholesterol (TC), triglyceride glucose index (TyG), triglyceride glucose-body mass index (TyG-BMI), and hypertension in this population.

METHODS

From June 2020 to July 2023, a total of 5042 Tibetans aged 18 to 80 years from three cities and one region in Tibet were randomly sampled for the study. Logistic regression analysis models combined with restricted cubic splines were used to analyze the relationship between LDL-C, TC, TyG, TyG-BMI index, and HTN in the Tibetan population.

RESULTS

(1) The prevalence of HTN in the Tibetan population in Tibet, China, was 32.35%, of which men were slightly higher than women. (2) Age, BMI, fasting blood glucose (FBG), uric acid (UA), TC, triglycerides (TG), LDL-C, homocysteine (Hcy), TyG, and TyG-BMI were higher in HTN populations compared to non-HTN populations (P < 0.05). (3) The risk of HTN was increased in individuals with borderline elevated and elevated LDL-C, borderline elevated TC, the second(Q2), third(Q3), and fourth quartile groups(Q4) of TyG as well as the third(Q3) and fourth quartile groups(Q4) of TyG-BMI. The prevalence risk of HTN gradually increased with elevated levels of LDL-C, TC, TyG, and TyG-BMI (P trend < 0.001). (4) The results of restricted cubic spline analysis showed a nonlinear dose-response relationship between LDL-C, TC, and TyG-BMI and the risk of developing HTN (P < 0.001, P Nonlinear < 0.05), and a linear dose-response relationship between TyG and the risk of developing HTN (P < 0.001, P Nonlinear > 0.05).

CONCLUSION

Higher LDL-C, TC, TyG, and TyG-BMI are risk factors for HTN in the Tibetan population of Tibet, China. Effective prevention can be achieved by controlling lipid and glucose indices.

Association of Lipid Levels With the Prevalence of Hypertension in Chinese Women: A Cross-Sectional Study Based on 32 Health Check Centers

BACKGROUND

Dyslipidemia is strongly associated with the development of hypertension. In our previous study, it was shown that elevated TC, LDL-c, and non-HDL-c were associated with the prevalence of hypertension in Chinese men, whereas the relationship between HDL-c and hypertension shifted from no association to a positive association after adjusting for the BMI. To further accumulate epidemiological evidence in Asian women, this study aimed to investigate the relationship between lipid profile and prevalence of hypertension in Chinese adult women.

METHODS

This is a cross-sectional study including 54,099 Chinese women aged>20 years at 32 health screening centers in 11 cities from 2010-2016. The original data were obtained from DATADRYAD database (www.datadryad.org). Besides, the overall women were classified into non-hypertensive and hypertensive groups based on baseline blood pressure levels. Differences between the two groups were examined by Man-Whitney test or Chi-square test. Spearman's correlation coefficient was employed to evaluate the correlation between systolic blood pressure (SBP), diastolic blood pressure (DBP) and lipid profiles. Multivariate logistic regression was performed to estimate the relationship between different lipid levels and the prevalence of hypertension. Odds ratios (ORs) and 95% confidence intervals (CIs) indicated the risk of lipid and hypertension. Bayesian model (BN) model was constructed to further assess the relationship between baseline characteristics and the prevalence of hypertension, as well as the importance of each variable for the prevalence of hypertension.

RESULTS

Compared to the non-hypertensive population, the hypertensive population was older, and had the higher body mass index (BMI), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-c), serum creatinine (Scr), fasting blood glucose (FPG), blood urea nitrogen (BUN), alanine aminotransferase (ALT), aspartate aminotransferase (AST), and non-high-density lipoprotein cholesterol (non-HDL-c), but HDL-c and the presence concerning the family history of diabetes were lower. Multivariate logistic regression analysis revealed that TC, LDL-c, and non-HDL-c showed a positive trend with hypertension risk (p for trend < 0.05) whereas TC and HDL-c were not significantly associated with hypertension prevalence. Moreover, each 1 mg/dl increase in TC, LDL, and non-HDL hypertension prevalence increased by 0.2% [1.002 (1.000-1.003)], 0.2% [1.002 (1.000-1.004)], and 0.2% [1.002(1.001-1.004)], respectively. BN suggested that the importance of age, BMI, FPG, non-HDL-c on the prevalence of hypertension was 52.73%, 24.98%, 11.22%, and 2.34%, respectively.

CONCLUSION

Overall, in Chinese adult women, TC, LDL-c and non-HDL-c levels were higher and HDL-c level was lower in the hypertensive population, whereas TG did not differ significantly from the non-hypertensive population. Meanwhile, TC, LDL-c, and non-HDL-c were positively associated with prevalence of hypertension, and HDL-c was negatively associated with prevalence of hypertension but became nonsignificant after full adjustment for variables. Moreover, BN model suggested that age, BMI, FPG, and non-HDL-c had a greater effect on the development of hypertension.

Lipid profiles and the risk of new-onset hypertension in a Chinese community-based cohort

BACKGROUND AND AIMS

Dyslipidemia and hypertension, key risk factors for cardiovascular disease, may share similar pathophysiological processes. A longitudinal association was reported between dyslipidemia and new-onset hypertension, but few data were published in Asian. We aimed to investigate the association of lipid profiles with new-onset hypertension in a Chinese community-based non-hypertensive cohort without lipid-lowering treatment (n = 1802).

METHODS AND RESULTS

New-onset hypertension was defined as any self-reported history of hypertension, systolic blood pressure ≥140 mmHg, or diastolic blood pressure ≥90 mmHg, or receiving antihypertensive medications at follow-up. Logistic regression models were used to evaluate the associations. Participants were aged 53.97 ± 7.49 years, 31.19% were men, and 64.54% with dyslipidemia. During a median of 2.30 years follow-up, the incidence of new-onset hypertension was 12.99%. Multivariate adjusted risks of new-onset hypertension increased with triglyceride increases (odds ratio [OR] = 1.14, 95% confidence interval [CI]: 1.03-1.27) and high-density lipoprotein cholesterol (HDL-C) decreases (OR = 0.47, 95% CI: 0.29-0.76) for one unit. However, threshold effects were observed for total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C) and non-HDL-C. Compared with subjects with hyperlipidemia, in those with normal concentrations of TC, LDL-C, and non-HDL-C increased risks of new-onset hypertension were observed with OR (95% CI) of 1.65 (1.10-2.46), 1.58 (1.07-2.33), and 1.57 (1.15-2.15) for one unit increasement, respectively, after adjusting for all covariates.

CONCLUSION

Higher TG and lower HDL-C increased the risk of new-onset hypertension, but for TC, LDL-C and non-HDLC, the risk of new-onset hypertension was increased only at normal concentrations in a Chinese community-based cohort.

Triglycerides and triglycerides to high-density lipoprotein cholesterol ratio are strong predictors of incident hypertension in Middle Eastern women

Dyslipidemia has been reported as a risk factor for incident hypertension in a few prospective studies, however, no study has specifically assessed different lipid measures including the lipid ratios, that is, total cholesterol (TC)/high-density lipoprotein cholesterol (HDL-C) and triglycerides (TGs)/HDL-C as predictors of hypertension among Middle Eastern women with high prevalences of dyslipidemia and hypertension. The study population consisted of 2831 non-hypertensive women, aged ≥ 20 years. We measured lipoproteins, and calculated non-HDL-C and the lipid ratios. The risk-factor-adjusted odds ratios for incident hypertension were calculated for every 1 standard deviation (s.d.) change in TC, log-transformed TG, HDL-C, non-HDL-C, TC/HDL-C and log-transformed TG/HDL-C using multivariate logistic regression analysis. Over a mean follow-up of 6.4 years, 397 women developed hypertension. An increase of 1 s.d. in TG, TC/HDL-C and TG/HDL-C increased the risk of incident hypertension by 16, 19 and 18%, respectively, and 1 s.d. increase in HDL-C decreased the risk of hypertension by 14% in the multivariable model (all P ≤ 0.05). In models excluding women with diabetes and central or general obesity, TG, TG/HDL-C and TC/HDL-C remained as independent predictors of incident hypertension. In conclusion, dyslipidemia, using serum TG and TG/HDL-C, in particular, may be useful in identification of women at risk of hypertension, even in those without diabetes and central or general obesity.

Adipocyte resistin mRNA levels are down-regulated by laparoscopic ovarian electrocautery in both obese and lean women with polycystic ovary syndrome

BACKGROUND

The aim of this study was to investigate serum and adipocyte mRNA expression of resistin in lean and obese women with polycystic ovary syndrome (PCOS) before and 3 months after laparoscopic ovarian electrocauterization (LOE).

METHODS

Adipose tissue obtained from 12 women with PCOS (six obese and six lean, body mass index > 27 kg m(-1) as threshold point) before and after LOE was analysed. Gene expression of resistin was measured by semi-quantitative RT-PCR. Ten lean, age-matched healthy women served as controls.

RESULTS

Both lean and obese women with PCOS had significantly higher fasting and 2 h insulin and homeostasis model insulin resistance index (HOMA(IR)) values and lower fasting glucose-to-insulin ratios (G(0)/I(0)) than did the controls. The serum levels of glucose and insulin and HOMA(IR) were significantly decreased, and the G(0)/I(0) ratio was significantly increased 3 months after LOE. No difference was found in serum resistin levels between controls and either obese or lean women with PCOS before LOE, nor between PCOS patients before and after LOE. However, resistin mRNA expression levels in both lean and obese women with PCOS before LOE were significantly higher than that in controls and were decreased significantly after LOE back to control levels.

CONCLUSION

Local resistin activity may be actively involved in the pathogenesis of PCOS. LOE reduces insulin resistance and down-regulates resistin mRNA expression in lean and obese women with PCOS.