Insulin Resistance and Hypertension

Benefits of Quercetin on Glycated Hemoglobin, Blood Pressure, PiKo-6 Readings, Night-Time Sleep, Anxiety, and Quality of Life in Patients with Type 2 Diabetes Mellitus: A Randomized Controlled Trial

Background: Diabetes is a rapidly growing global morbidity issue with high prevalence, and the associated dysglycemia leads to complications. Patients with type 2 diabetes mellitus (T2DM) often experience elevated anxiety levels, affecting their quality of life and diabetes management. This study investigated quercetin, a nutraceutical and potential senolytic with antioxidant activity, to detect its possible positive effect on the bio-clinical measurements and routine health of patients with T2DM. Methods: This prospective randomized controlled trial (RCT) investigated the clinical usefulness of quercetin in patients with T2DM receiving non-insulin medications. One hundred participants were stratified by age and sex (1:1) and randomized to control (n = 50) or intervention (n = 50) groups. The control received standard care only, while the intervention received 500 mg quercetin daily for 12 weeks, followed by an 8-week washout and a final consecutive 12-week supplementation period (total: 32 weeks), as adjunct to their usual care. Comprehensive health assessments, including blood analyses, were conducted at baseline and study termination. Quality of life and anxiety were assessed using the 36-item Short Form Health Survey (SF-36) and Short Anxiety Screening Test (SAST-10). Results: Eighty-eight patients with T2DM concluded the trial. Compared with the control, glycated hemoglobin (HbA1c) levels showed a significant decrease (Δ%-change: -4.0% vs. 0.1%, p = 0.011). Quercetin also significantly improved PiKo-6 readings (FEV1: 5.6% vs. -1.5%, p = 0.002), systolic blood pressure (-5.0% vs. -0.2%, p = 0.029), night-time sleep (11.6% vs. -7.3%, p < 0.001), anxiety levels (SAST-10) (-26.2% vs. 3.3%, p < 0.001), and quality of life (SF-36) (both physical and mental components, p < 0.001). Conclusions: Based on the current open-label study, quercetin appears to be a promising supplement for T2DM, providing lifestyle and care support. Further research is warranted to shift this potential from clinical usefulness and feasibility to multidisciplinary evidence.

Additive interactions between obesity and insulin resistance on hypertension in a Chinese rural population

BACKGROUND

Adiposity and insulin resistance (IR) are closely associated with hypertension; however, the role of interactions between obesity phenotypes and IR in hypertension is unclear. This study aimed to evaluate the interactions of body mass index (BMI), waist circumference (WC), and body fat percentage (BF%) with IR on hypertension risk.

METHODS

We analyzed data from 4888 participants (mean age 57 years, 41.2% men) in the China Northwest Natural Population Cohort, Ningxia Project. BMI, WC, and BF% were determined using bioelectrical impedance analysis devices. IR was estimated using a homeostasis model assessment index (HOMA-IR). Multivariable-adjusted logistic regression was used to evaluate the association between HOMA-IR and hypertension risk. We calculated the relative excess risk and attributable proportion with their 95% confidence intervals (CIs) to assess whether adiposity phenotypes modified the effect of HOMA-IR on hypertension risk.

RESULTS

The crude prevalence of hypertension was 52.2%. The multivariable-adjusted odds ratio of HOMA-IR was 1.80 (95% CI: 1.23-2.65) for the risk of hypertension in the highest versus the lowest quartiles, but this association became marginal in models further adjusting for BMI, WC, and BF% (P for trend = 0.056). Relative excess risk and attributable proportion for interaction between high HOMA-IR and high BF% were 0.32 (0.04-0.59) and 0.33 (0.06-0.60), respectively. Additionally, high truncal and leg BF% and high HOMA-IR accounted for the hypertension risk in women, but not in men. We did not observe any significant interactions between BMI or WC and HOMA-IR on hypertension.

CONCLUSION

BF% modified the association between IR and increased risk of hypertension in women with high truncal and leg BF%, but not in men.

Association between insulin resistance and uncontrolled hypertension and arterial stiffness among US adults: a population-based study

BACKGROUND

Prior research has established the correlation between insulin resistance (IR) and hypertension. While the association between triglyceride-glucose (TyG) index, a reliable surrogate marker of IR, and uncontrolled hypertension as well as arterial stiffness among individuals with hypertension remains undisclosed.

METHODS

In this study, a total of 8513 adults diagnosed with hypertension from the National Health and Nutrition Examination Survey 1999-2018 were included. The primary outcome of the study are arterial stiffness (represented with estimated pulse wave velocity, ePWV) and uncontrolled hypertension. Logistic regression model, subgroup analysis, restricted cubic spine, and smooth curve fitting curve were conducted to evaluate the association between the IR indicators and uncontrolled hypertension and arterial stiffness in individuals with hypertension.

RESULTS

Among included participants, the overall prevalence of uncontrolled hypertension was 54.3%. After adjusting for all potential covariates, compared with the first quartile of TyG index, the risk of uncontrolled hypertension increased about 28% and 49% for participants in the third quartile (OR, 1.28; 95% CI 1.06-1.52) and the fourth quartile (OR, 1.49; 95% CI 1.21-1.89) of TyG index, respectively. The higher OR of TyG index was observed in participants taking antihypertensive medication [fourth quartile versus first quartile (OR, 2.03; 95% CI 1.37-3.11)]. Meanwhile, we explored the potential association between TyG index and arterial stiffness and found that TyG index was significantly associated with increased arterial stiffness (β for ePWV, 0.04; 95% CI 0.00-0.08; P = 0.039). However, traditional IR indicator HOMA-IR showed no significant positive correlation to uncontrolled hypertension as well as arterial stiffness in US adults with hypertension.

CONCLUSION

Elevated levels of the TyG index were positive associated with prevalence of uncontrolled hypertension and arterial stiffness among US adults with hypertension.

Cord Blood Insulin Concentration and Hypertension Among Children and Adolescents Enrolled in a US Racially Diverse Birth Cohort

BACKGROUND

Although insulin resistance is closely related to hypertension, the debate continues as to whether insulin resistance is a cause or a consequence of hypertension. This study investigated the associations of cord blood insulin concentration with blood pressure (BP) and hypertension in childhood and adolescence.

METHODS

This study included 951 children enrolled from 1998 to 2012 and followed from birth onwards at the Boston Medical Center, Boston, MA. Cord blood insulin concentration was measured using a sandwich immunoassay. Hypertension in childhood and adolescence was defined based on the 2017 American Academy of Pediatrics Clinical Practice Guidelines.

RESULTS

The median (interquartile range) for cord blood insulin concentration was 12.1 (7.2-19.0) µIU/mL. The age range of BP measurements was 3 to 18 years (median, 10.6 years). Cord blood insulin concentration was positively associated with systolic and diastolic BP as well as the risk of hypertension at age 3 to 18 years. Compared with the lowest tertile of cord blood insulin concentration, the top tertile insulin concentration was associated with a 5.18 (95% CI, 1.97-8.39) percentile increase in systolic BP, 4.29 (95% CI, 1.74-6.84) percentile increase in diastolic BP, and 1.62-fold (95% CI, 1.27-2.08) higher risk of hypertension. The association between insulin and hypertension was stronger among children born preterm (P for interaction=0.048). Furthermore, preterm birth and childhood overweight or obesity enhanced the associations.

CONCLUSIONS

Our results suggest that elevated insulin concentration at birth plays a critical role in the early life origins of hypertension and support the hypothesis implicating insulin resistance in the etiology of hypertension.

Triglyceride Glucose Index for Predicting Major Adverse Cardiovascular Events in Chinese Patients with Hypertension

We conducted a longitudinal study (from February 2017 to July 2017) to explore whether the triglyceride glucose index (TyG) index has a prognostic value for major adverse cardiovascular events (MACE) among high-risk Chinese hypertensives. The study population were from 6 districts of Tianjin, China. Finally, a total of 2250 patients were enrolled in this 3.5 year cohort study. The patients were divided into two groups according to the cut-off value of the TyG index: Low-TyG group (n = 901, TyG ≤ 8.87), High-TyG group (n = 1349, TyG > 8.87). Univariate and multivariate Cox regression analyses were used to estimate the relationship between the TyG and MACE. In multivariate cox regression analyses, the hazard ratio (HR) (95% confidence interval (CI)) of the high-TyG group was 1.313 (1.010, 1.708) compared with the low-TyG group. In those with an age ≤65 years and male subgroups, the prediction value of TyG was higher, and the risk of occurrence of MACE greater after adjusting other risk factors. The TyG index is an indicator to predict the development of MACE in hypertensive patients.

Preeclampsia and the Kidney: Pathophysiology and Clinical Implications

Preeclampsia and other hypertensive disorders of pregnancy are major contributors to maternal morbidity and mortality worldwide. This group of disorders includes chronic hypertension, gestational hypertension, preeclampsia, preeclampsia superimposed on chronic hypertension, and eclampsia. The body undergoes important physiological changes during pregnancy to allow for normal placental and fetal development. Several mechanisms have been proposed that may lead to preeclampsia, including abnormal placentation and placental hypoxia, impaired angiogenesis, excessive pro-inflammatory response, immune system imbalance, abnormalities of cellular senescence, alterations in regulation and activity of angiotensin II, and oxidative stress, ultimately resulting in upregulation of multiple mediators of endothelial cell dysfunction leading to maternal disease. The clinical implications of preeclampsia are significant as there are important short-term and long-term health consequences for those affected. Preeclampsia leads to increased risk of preterm delivery and increased morbidity and mortality of both the developing fetus and mother. Preeclampsia also commonly leads to acute kidney injury, and women who experience preeclampsia or another hypertensive disorder of pregnancy are at increased lifetime risk of chronic kidney disease and cardiovascular disease. An understanding of normal pregnancy physiology and the pathophysiology of preeclampsia is essential to develop novel treatment approaches and manage patients with preeclampsia and hypertensive disorders of pregnancy. © 2023 American Physiological Society. Compr Physiol 13:4231-4267, 2023.

Comparison of Fasting Insulin Level, Homeostatic Model of Insulin Resistance, and Lipid Levels between Patients with Primary Hypertension and Normotensive Subjects

BACKGROUND

Hyperinsulinemia and insulin resistance occurs in obese patients with primary hypertension independent of diabetes and obesity. This study was aimed at assessing serum fasting insulin levels, the homeostatic model assessment for insulin resistance (HOMA-IR), and serum lipid levels in non-obese patients with primary hypertension when compared to normotensive subjects.

METHODS

This observational study comprised 100 patients over 18 years of age, divided into two groups. The hypertensive group comprised non-obese patients with primary hypertension (n=50); the normotensive group comprised normotensive age- and sex-matched individuals (n=50). Patients with diabetes, impaired fasting glucose, obesity, and other causative factors of insulin resistance were excluded from the study. Serum fasting insulin levels and fasting lipid profiles were measured, and insulin resistance was calculated using HOMA-IR. These data were compared between the two groups. Pearson's correlation coefficient was used to assess the extent of a linear relationship between HOMA-IR and to evaluate the association between HOMA-IR and systolic and diastolic blood pressures.

RESULTS

Mean serum fasting insulin levels (mIU/L), mean HOMA-IR values, and fasting triglyceride levels (mg/dL) were significantly higher in the hypertensive versus normotensive patients (10.32 versus 6.46, P<0.001; 1.35 versus 0.84, P<0.001; 113.70 versus 97.04, P=0.005, respectively). The HOMA-IR levels were associated with systolic blood pressure (r value 0.764, P=0.0005).

CONCLUSION

We observed significantly higher fasting insulin levels, serum triglyceride levels, and HOMA-IR reflecting hyperinsulinemia and possibly an insulin-resistant state among primary hypertension patients with no other causally linked factors for insulin resistance. We observed a significant correlation between systolic blood pressure and HOMA-IR.

Insulin resistance, metabolic syndrome, and blood pressure progression among Blacks: the Jackson Heart Study

OBJECTIVE

There is a paucity of data on the relations of insulin resistance with incident blood pressure (BP) changes among Blacks. We investigated the associations of insulin resistance and metabolic syndrome (MetS) with BP progression in a community-based sample of African Americans.

METHODS

We analyzed 1064 participants without hypertension at baseline (2000-2004) who attended at least one follow-up visit in 2005-2008 or 2009-2013. Four insulin resistance indices [fasting insulin, insulin-to-glucose ratio (IGR), homeostasis model assessment of insulin resistance (HOMA-IR), and quantitative insulin sensitivity check index (QUICKI)] and MetS (excluding hypertension in the definition) were assessed at baseline. Robust Poisson regression was used to generate risk ratios (RRs) and 95% confidence intervals (CI) for BP progression and incident hypertension.

RESULTS

Over a median of 7 years, 69.6% progressed to a higher BP category and 62.7% developed hypertension. After multivariable adjustment, participants in the highest quartile of HOMA-IR had higher risks of BP progression [RR 1.25 (95% CI 1.09-1.43), Ptrend = 0.004] and hypertension [RR 1.35 (95% CI 1.16-1.58), Ptrend < 0.001] compared with those in the lowest quartile. A similar positive association of insulin resistance with BP outcomes was noted with insulin resistance assessed using IGR, fasting insulin, and QUICKI. MetS was associated with increased risks of BP progression [RR 1.15 (95% CI 1.02-1.30), P = 0.02] and incident hypertension [RR 1.23 [95% CI 1.08-1.41], P = 0.002]. These associations were present across baseline BP categories.

CONCLUSION

Our findings support the notion that higher insulin resistance levels are associated with greater risks of BP progression and incident hypertension among Blacks.

Hypertension in Diabetes: An Update of Basic Mechanisms and Clinical Disease

Epidemiological studies have documented that insulin resistance and diabetes not only constitute metabolic abnormalities but also predispose to hypertension, vascular stiffness, and associated cardiovascular disease. Meanwhile, excessive arterial stiffness and impaired vasorelaxation, in turn, contribute to worsening insulin resistance and the development of diabetes. Molecular mechanisms promoting hypertension in diabetes include inappropriate activation of the renin-angiotensin-aldosterone system and sympathetic nervous system, mitochondria dysfunction, excessive oxidative stress, and systemic inflammation. This review highlights recent studies which have uncovered new underlying mechanisms for the increased propensity for the development of hypertension in association with diabetes. These include enhanced activation of epithelial sodium channels, alterations in extracellular vesicles and their microRNAs, abnormal gut microbiota, and increased renal sodium-glucose cotransporter activity, which collectively predispose to hypertension in association with diabetes. This review also covers socioeconomic factors and currently recommended blood pressure targets and related treatment strategies in diabetic patients with hypertension.

Assessment of preferred methods to measure insulin resistance in Asian patients with hypertension

Insulin resistance (IR), a metabolic risk factor, is linked to the pathogenetic mechanism of primary hypertension. Detecting IR in the patients with hypertension will help to predict and stratify the added cardiovascular risk, institute appropriate IR management, and manage hypertension optimally. There are many methods for assessing IR, each with distinct advantages and disadvantages. The euglycemic insulin clamp and intravenous glucose tolerance test, gold standards for measuring IR, are used in research but not in clinical practice. Homeostatic model assessment (HOMA-IR), a method for assessing β-cell function and IR, is frequently applied presently, particularly in Asia. Besides, the triglyceride-glucose index (TyG) first published by South American authors showed a good correlation with the insulin clamp technique and HOMA-IR index. This simple, convenient, and low-cost TyG index is of research interest in many countries in Asia and can be used to screen for IR in the Asian hypertensive community.

Effectiveness of Bariatric Surgery in Patients with the Metabolically Healthy Obese Phenotype

BACKGROUND

To evaluate the effectiveness and safety of bariatric surgery in metabolically healthy obese (MHO) patients.

METHODS

In this retrospective, observational study, we reviewed the medical records of patients who underwent bariatric surgery at a tertiary care hospital between January 2007 and March 2015. Patients who underwent revisional surgery and patients with type 1 diabetes were excluded from the analysis. MHO patients were defined as those without a previous diagnosis of diabetes or atherogenic dyslipidemia and absence of hypoglycemic treatment or treatment with fibrates.

RESULTS

A total of 188 patients were included (mean age 48.97 ± 10.32 years, 68.6% of women). Sleeve gastrectomy was performed in 121 patients (64%) and a gastric bypass in 67 patients (36%). Prior to surgery, 36 patients (19%) were MHO. In the second- and third-year post-surgery, MHO patients presented a higher percentage of total weight loss (%TWL) (35.16% vs. 30.34%; p = 0.02 and 33.97% vs. 27.78%; p = 0.013 respectively). Multiple regression analysis showed that MHO was associated with a higher weight loss irrespective of age, sex, baseline BMI, and type of surgery. We did not detect any differences in acute complications between patients with and without MHO after bariatric surgery.

CONCLUSIONS

Bariatric surgery in MHO patients in our study was associated with higher weight loss than that in MUHO patients. There were no differences between the two groups in respect to acute complications following surgery.

Factors leading to high morbidity and mortality of COVID-19 in patients with type 2 diabetes

Coronavirus disease 2019 (COVID-19) is a recent pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a novel coronavirus. Diabetes (mostly type 2 diabetes mellitus, T2DM) and hyperglycemia are among the major comorbidities in patients with COVID-19 leading to poor outcomes. Reports show that patients with diabetes and COVID-19 are at an increased risk for developing severe complications including acute respiratory distress syndrome, multi-organ failure, and death. Here we explore potential mechanistic links that could explain the observed higher morbidity and mortality in this patient population. Patients with T2DM have an underlying increased level of inflammation associated with obesity and insulin resistance in addition to other comorbidities including hypertension, obesity, cardiovascular disease, dyslipidemia, and being older. We review evidence that T2DM with hyperglycemia are among factors that lead to elevated expression of angiotensin-converting enzyme 2 (ACE2) in lungs and other tissues; ACE2 is the cellular "receptor" and port of viral entry. The preexisting chronic inflammation with augmented inflammatory response to the infection and the increasing viral load leads to extreme systemic immune response ("cytokine storm") that is strongly associated with increased severity of COVID-19. Based on the available evidence, it is recommended by a panel of experts that safe but stringent control of blood glucose, blood pressure, and lipids be carried out in patients with T2DM, measures that could potentially serve to decrease the severity of COVID-19 should these patients contract the viral infection. Once the infection occurs, then attention should be directed to proper glycemic control with use of insulin and frequent monitoring of blood glucose levels.

20-HETE interferes with insulin signaling and contributes to obesity-driven insulin resistance

20-HETE, a metabolite of arachidonic acid produced by Cytochrome P450 (CYP) 4A/4 F, has been implicated in the development of obesity-associated complications such as diabetes and insulin resistance. In this study, we examined whether the acute elevation of 20-HETE levels contributes to the development of diet-driven hyperglycemia and insulin resistance. We employed a conditional transgenic mouse model to overexpress Cyp4a12 (Cyp4a12tg), a murine 20-HETE synthase, together with high fat diet (HFD) feeding. Mice in which Cyp4a12 was induced by doxycycline (DOX) at the onset of HFD feeding gained weight at a greater rate and extent than corresponding DOX-untreated Cyp4a12 mice. Cyp4a12tg mice fed HFD + DOX displayed hyperglycemia and impaired glucose metabolism while corresponding HFD-fed Cyp4a12tg mice (no DOX) did not. Importantly, administration of a 20-HETE antagonist, 20-SOLA, to Cyp4a12tg mice fed HFD + DOX significantly attenuated weight gain and prevented the development of hyperglycemia and impaired glucose metabolism. Levels of insulin receptor (IR) phosphorylation at Tyrosine 972 and insulin receptor substrate-1 (IRS1) phosphorylation at serine 307 were markedly decreased and increased, respectively, in liver, skeletal muscle and adipose tissues from Cyp4a12tg mice fed HFD + DOX; 20-SOLA prevented the IR and IRS1 inactivation, suggesting that 20-HETE interferes with insulin signaling. Additional studies in 3T3-1 differentiated adipocytes confirmed that 20-HETE impairs insulin signaling and that its effect may require activation of its receptor GPR75. Taken together, these results provide strong evidence that 20-HETE interferes with insulin function and contributed to diet-driven insulin resistance.

Chronic hypertension in pregnancy

Chronic hypertension and associated cardiovascular disease are among the leading causes of maternal and perinatal morbidity and death in the United States. Chronic hypertension in pregnancy is associated with a host of adverse outcomes that include preeclampsia, cesarean delivery, cerebrovascular accidents, fetal growth restriction, preterm birth, and maternal and perinatal death. There are several key issues related to the diagnosis and management of chronic hypertension in pregnancy where data are limited and further research is needed. These challenges and recent guidelines for the management of chronic hypertension are reviewed. Well-timed pregnancies are of utmost importance to reduce the risks of chronic hypertension; long-acting reversible contraceptive options are preferred. Research to determine optimal blood pressure thresholds for diagnosis and treatment to optimize short- and long-term maternal and perinatal outcomes should be prioritized along with interventions to reduce extant racial and ethnic disparities.

The Effect of Hypertension Duration and the Age of Onset on CV Risk Factors Expression in Perimenopausal Women

Background

The impact of hypertension duration and the time of onset on the expression of metabolic syndrome (MS) and other CV risk factors, in perimenopausal women, have not been studied so far. Methods. A total of 202 women, old 47–59 years, and diagnosed with hypertension, were recruited from primary care practices in eastern Croatia. The categories of hypertension duration were defined as <5, 5–10, and >10 years. Data were analyzed by standard statistical procedures.

Results

The proportion of women with MS increases in parallel with hypertension duration (p = 0.025). Among the examined CV risk factors, significant increase in parallel with hypertension duration was found for body mass index (p = 0.007) and triglycerides (p = 0.07). The highest proportion of women with diabetes duration of less than 5 years, indicating recent diabetes onset, was found in the category of hypertension duration of less than 5 years, corresponding with the onset of hypertension in the time around menopause (p = 0.003). The strongest linear correlations with BMI and waist circumference were found for total serum cholesterol (r = 0.355 and 0.499, respectively).

Conclusion

Hypertension onset at the time around menopause appears together with abdominal obesity and may be a driving force for CV risk factor accumulation in postmenopausal women.

Wrist circumference is associated with increased systolic blood pressure in children with overweight/obesity

Wrist circumference is a clinical marker for insulin-resistance in overweight/obese children and adolescents. Insulin resistance is considered a major determinant of increased vascular resistance and hypertension. The aim of the study was to investigate the association between wrist circumference and systolic (S) and diastolic (D) blood pressure (BP) in a population of overweight/obese children and adolescents. A population of 1133 overweight/obese children and adolescents (n = 1133) were consecutively enrolled. Multivariate regression analyses were used to investigate the influence of independent variables on the variance of BP. The prevalence of hypertension was 21.74% in males and 28.95% in females (p = 0.048). The results showed that SBP was significantly associated with wrist circumference in both genders (p < 0.0001 for both comparisons). We found no association between DBP and wrist circumference in either gender. Wrist circumference accounted for 17% of the total variance of SBP in males and 14% in females. Wrist circumference, a marker of insulin resistance, is associated with increased SBP in overweight/obese children and adolescents, suggesting a role of insulin resistance in the pathogenesis and development of hypertension.

Chronic hypertension and adverse pregnancy outcome: a cohort study

OBJECTIVE

To examine the association between chronic hypertension (CH) and a wide range of adverse pregnancy outcomes after adjustment for confounding factors in obstetric history and maternal characteristics.

METHODS

This was a prospective screening study for adverse pregnancy outcomes in women with singleton pregnancy attending their first routine hospital visit at 11 + 0 to 13 + 6 weeks' gestation. Data on maternal characteristics, medical and obstetric history and pregnancy outcome were collected. Regression analysis was performed to examine the association between CH and adverse pregnancy outcomes, including late miscarriage, stillbirth, pre-eclampsia (PE), gestational diabetes mellitus (GDM), spontaneous and iatrogenic preterm birth (PTB), small-for-gestational-age (SGA) neonate, large-for-gestational-age (LGA) neonate and elective and emergency Cesarean section (CS).

RESULTS

The study population of 109 932 pregnancies included 1417 (1.3%) women with CH. After adjusting for potential confounding variables from maternal characteristics, medical and obstetric history, CH was associated with increased risk of stillbirth (odds ratio (OR), 2.38 (95% CI, 1.51-3.75)), PE (OR, 5.76 (95% CI, 4.93-6.73)), SGA (OR, 2.06 (95% CI, 1.79-2.39)), GDM (OR, 1.61 (95% CI, 1.27-2.05)), iatrogenic PTB < 37 weeks (OR, 3.73 (95% CI, 3.07-4.53)) and elective CS (OR, 1.79 (95% CI, 1.52-2.11)), decreased risk of LGA (OR, 0.65 (95% CI, 0.53-0.78)) and had no significant effect on late miscarriage, spontaneous PTB or emergency CS.

CONCLUSION

CH should be combined with other maternal characteristics and medical and obstetric history when calculating an individualized adjusted risk for adverse pregnancy complications. CH increases the risk of stillbirth, PE, SGA, GDM, iatrogenic PTB and elective CS and reduces the risk for LGA. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Dietary intake and cardiometabolic biomarkers in relation to insulin resistance and hypertension in a middle-aged and elderly population in Beijing, China

This study investigated the relationships of dietary intake and cardiometabolic biomarkers with insulin resistance and hypertension in rural middle-aged and elderly people in China. One hundred and eight middle-aged and elderly adults were recruited in Zhangfang village in May 2014. We measured blood pressure, anthropometric parameters, and biochemical indexes, including high-sensitivity C-reactive protein (hsCRP), soluble intercellular adhesion molecule-1 (sICAM-1), glucose, insulin, and blood lipids. Homeostasis model assessment of insulin resistance index (HOMA-IR) was assessed on the basis of fasting glucose and insulin. We recorded participant demographic characteristics, dietary intake, and lifestyle using questionnaires. Hypertensive participants had higher levels of triglycerides (TG), hsCRP, sICAM-1, body fat percentage (BF%), arm muscle circumference (AMC) and HOMA-IR than nonhypertensive individuals. Hypertensive participants had higher carbohydrate intake but lower intakes of protein and fat. Carbohydrate intake was positively correlated with hsCRP, sICAM-1, TG, BF%, and HOMA-IR, and was negatively correlated with AMC. Protein and fat intakes were negatively correlated with hsCRP and sICAM-1. Protein intake was also significantly negatively correlated with TG and HOMA-IR, and positively correlated with AMC. HOMA-IR was positively correlated with hsCRP, sICAM-1, TG and BF%, and negatively correlated with AMC. Multivariable linear regression indicated that TG, sICAM-1, and hsCRP were significantly associated with HOMA-IR. In conclusion, in a rural Chinese population, high intake of carbohydrate and low intake of fat and protein were associated with insulin resistance and hypertension, possibly by increasing inflammatory factors such as sICAM-1 and hsCRP, increasing BF% and increasing the level of plasma TG.

Effects of grape seed extract beverage on blood pressure and metabolic indices in individuals with pre-hypertension: a randomised, double-blinded, two-arm, parallel, placebo-controlled trial

The aim of the present study was to test grape seed extract (GSE) as a functional ingredient to lower blood pressure (BP) in individuals with pre-hypertension. A single-centre, randomised, two-arm, double-blinded, placebo-controlled, 12-week, parallel study was conducted in middle-aged adults with pre-hypertension. A total of thirty-six subjects were randomised (1:1) to Placebo (n 18) or GSE (n 18) groups; twenty-nine of them completed all the protocol-specified procedures (Placebo, n 17; GSE, n 12). Subjects consumed a juice (167 kJ (40 kcal)) containing 0 mg (Placebo) or 300 mg/d GSE (150 mg) twice daily for 6 weeks preceded by a 2-week Placebo run-in and followed by 4-week no-beverage follow-up. Compliance was monitored. BP was measured at screening, 0, 6 and 10 weeks of intervention and blood samples were collected at 0, 3, 6 and 10 weeks of intervention. GSE significantly reduced systolic BP (SBP) by 5·6 % (P=0·012) and diastolic BP (DBP) by 4·7 % (P=0·049) after 6 weeks of intervention period, which was significantly different (SBP; P=0·03) or tended to be different (DBP; P=0·08) from Placebo. BP returned to baseline after the 4-week discontinuation period of GSE beverage. Subjects with higher initial BP experienced greater BP reduction; nearly double the effect size. Fasting insulin and insulin sensitivity tended to improve after 6 weeks of GSE beverage supplementation (P=0·09 and 0·07, respectively); no significant changes were observed with fasting plasma lipids, glucose, oxidised LDL, flow-mediated dilation or vascular adhesion molecules. Total plasma phenolic acid concentrations were 1·6 times higher after 6 weeks of GSE v. Placebo. GSE was found to be safe and to improve BP in people with pre-hypertension, supporting the use of GSE as a functional ingredient in a low-energy beverage for BP control.

Impact of Adiposity on Incident Hypertension Is Modified by Insulin Resistance in Adults: Longitudinal Observation From the Bogalusa Heart Study

Adiposity and insulin resistance are closely associated with hypertension. This study aims to investigate whether the association between adiposity and hypertension is modified by insulin resistance. The cohort consisted of 1624 middle-aged normotensive black and white adults aged 18 to 43 years at baseline who followed for 16 years on average. Overweight/obesity at baseline was defined as body mass index (BMI) ≥25, and insulin resistance was measured using homeostasis model assessment of insulin resistance. Prevalence of incident hypertension was compared between the insulin-sensitive adiposity and insulin-resistant adiposity groups. The prevalence of incident hypertension was higher in the insulin-resistant adiposity than in the insulin-sensitive adiposity group (32.1% versus 22.1%, P<0.001). In multivariable logistic analyses, adjusted for baseline age, race, sex, follow-up years, and smoking, baseline insulin-resistant obesity was associated with incident hypertension (odds ratio, 1.9; P=0.008). Odds ratios did not differ between blacks and whites (P=0.238). Of note, the odds ratios of BMI associated with hypertension significantly increased with increasing quartiles of baseline homeostasis model assessment (odds ratio, 1.3, 1.1, 1.5, and 2.5 in quartiles I, II, III, and IV, respectively; P=0.006 for trend). Slopes of increasing follow-up blood pressure with baseline BMI, measured as regression coefficients (β), were significantly greater in insulin-resistant than in insulin-sensitive individuals (β=0.74 versus β=0.35 for systolic blood pressure, P=0.004 for difference; β=0.51 versus β=0.23 for diastolic blood pressure, P=0.001 for difference). These findings suggest that insulin resistance has a synergistic effect on the obesity-hypertension association in young adults, indicating that the role of adiposity in the development of hypertension is modified by insulin resistance.

The effect of tree nut, peanut, and soy nut consumption on blood pressure: a systematic review and meta-analysis of randomized controlled clinical trials

BACKGROUND

Although several studies have assessed the effects of nut consumption (tree nuts, peanuts, and soy nuts) on blood pressure (BP), the results are conflicting.

OBJECTIVE

The aim was to conduct a systematic review and meta-analysis of published randomized controlled trials (RCTs) to estimate the effect of nut consumption on BP.

DESIGN

The databases MEDLINE, SCOPUS, ISI Web of Science, and Google Scholar were searched for RCTs carried out between 1958 and October 2013 that reported the effect of consuming single or mixed nuts (including walnuts, almonds, pistachios, cashews, hazelnuts, macadamia nuts, pecans, peanuts, and soy nuts) on systolic BP (SBP) or diastolic BP (DBP) as primary or secondary outcomes in adult populations aged ≥18 y. Relevant articles were identified by screening the abstracts and titles and the full text. Studies that evaluated the effects for <2 wk or in which the control group ingested different healthy oils were excluded. Mean ± SD changes in SBP and DBP in each treatment group were recorded for meta-analysis.

RESULTS

Twenty-one RCTs met the inclusion criteria. Our findings suggest that nut consumption leads to a significant reduction in SBP in participants without type 2 diabetes [mean difference (MD): -1.29; 95% CI: -2.35, -0.22; P = 0.02] but not in the total population. Subgroup analyses of different nut types suggest that pistachios, but not other nuts, significantly reduce SBP (MD: -1.82; 95% CI: -2.97, -0.67; P = 0.002). Our study suggests that pistachios (MD: -0.80; 95% CI: -1.43, -0.17; P = 0.01) and mixed nuts (MD: -1.19; 95% CI: -2.35, -0.03; P = 0.04) have a significant reducing effect on DBP. We found no significant changes in DBP after the consumption of other nuts.

CONCLUSIONS

Total nut consumption lowered SBP in participants without type 2 diabetes. Pistachios seemed to have the strongest effect on reducing SBP and DBP. Mixed nuts also reduced DBP.

Fasting insulin concentrations and incidence of hypertension, stroke, and coronary heart disease: a meta-analysis of prospective cohort studies

BACKGROUND

Insulin resistance is a precursor of numerous chronic diseases, including cardiovascular disease (CVD). The fasting insulin concentration is considered a reasonable surrogate of insulin resistance, especially among nondiabetic individuals.

OBJECTIVE

We aimed to quantitatively summarize the literature on the association of fasting insulin concentrations with risk of hypertension, stroke, and coronary heart disease (CHD) by conducting a meta-analysis of prospective cohort studies.

DESIGN

Eligible studies were identified by searching PubMed and EMBASE through January 2013. Additional information was retrieved through Google Scholar or a hand review of the reference lists from relevant articles. Prospective cohort studies that reported RRs and corresponding 95% CIs for the association of interest were identified. Data were extracted independently by 2 investigators, and the weighted RRs and 95% CIs for the associations were obtained by using a random-effects model.

RESULTS

Of the 22 identified studies, 10 reported results on hypertension (36,617 individuals and 4491 cases), 7 on stroke (27,887 individuals and 1550 cases), and 9 on CHD (22,379 individuals and 1986 cases). Comparison of the highest with the lowest quantile of fasting insulin concentrations showed a pooled RR (95% CI) of 1.63 (1.35, 1.97) for hypertension, 1.18 (0.87, 1.60) for stroke, and 1.50 (1.28, 1.77) for CHD. Each 50-pmol/L increment in fasting insulin was associated with a 25% increase in risk of hypertension [RR: 1.25 (1.14, 1.36)] and a 16% increase in risk of CHD [RR: 1.16 (1.10, 1.22)] but was not associated with risk of stroke [RR: 0.999 (0.99, 1.01)].

CONCLUSIONS

A higher fasting insulin concentration or hyperinsulinemia was significantly associated with an increased risk of hypertension and CHD but not stroke. This meta-analysis suggests that early fasting insulin ascertainment in the general population may help clinicians identify those who are potentially at high risk of CVD.

In-treatment HDL cholesterol levels and development of new diabetes mellitus in hypertensive patients: the LIFE Study

AIMS

Although hypertensive patients with low baseline HDL cholesterol levels have a higher incidence of diabetes mellitus, whether changing levels of HDL over time are more strongly related to the risk of new diabetes in hypertensive patients has not been examined.

METHODS

Incident diabetes mellitus was examined in relation to baseline and in-treatment HDL levels in 7485 hypertensive patients with no history of diabetes randomly assigned to losartan- or atenolol-based treatment.

RESULTS

During 4.7 ± 1.2 years follow-up, 520 patients (6.9%) developed new diabetes. In univariate Cox analyses, compared with the highest quartile of HDL levels (> 1.78 mmol/l), baseline and in-treatment HDL in the lowest quartile (< 1.21 mmol/l) identified patients with > 5-fold and > 9 fold higher risks of new diabetes, respectively; patients with baseline or in-treatment HDL in the 2nd and 3rd quartiles had intermediate risk of diabetes. In multivariable Cox analyses, adjusting for randomized treatment, age, sex, race, prior anti-hypertensive therapy, baseline uric acid, serum creatinine and glucose entered as standard covariates, and in-treatment non-HDL cholesterol, Cornell product left ventricular hypertrophy, diastolic and systolic pressure, BMI, hydrochlorothiazide and statin use as time-varying covariates, the lowest quartile of in-treatment HDL remained associated with a nearly 9-fold increased risk of new diabetes (hazard ratio 8.7, 95% CI 5.0-15.2), whereas the risk of new diabetes was significantly attenuated for baseline HDL < 1.21 mmol/l (hazard ratio 3.9, 95% CI 2.8-5.4).

CONCLUSIONS

Lower in-treatment HDL is more strongly associated with increased risk of new diabetes than baseline HDL level.

Fasting insulin level is positively associated with incidence of hypertension among American young adults: a 20-year follow-up study

OBJECTIVE

Although hyperinsulinemia, a surrogate of insulin resistance, may play a role in the pathogenesis of hypertension (HTN), the longitudinal association between fasting insulin level and HTN development is still controversial. We examined the relation between fasting insulin and incidence of HTN in a large prospective cohort.

RESEARCH DESIGN AND METHODS

A prospective cohort of 3,413 Americans, aged 18-30 years, without HTN in 1985 (baseline) were enrolled. Six follow-ups were conducted in 1987, 1990, 1992, 1995, 2000, and 2005. Fasting insulin and glucose levels were assessed by a radioimmunoassay and hexokinase method, respectively. Cox proportional hazards models were used to calculate hazard ratios (HRs) and 95% CIs of incident HTN (defined as the initiation of antihypertensive medication, systolic blood pressure ≥140 mmHg, or diastolic blood pressure ≥90 mmHg).

RESULTS

During the 20-year follow-up, 796 incident cases were identified. After adjustment for potential confounders, participants in the highest quartile of insulin levels had a significantly higher incidence of HTN (HR 1.85 [95% CI 1.42-2.40]; P(trend) < 0.001) compared with those in the lowest quartile. The positive association persisted in each sex/ethnicity/weight status subgroup. A similar dose-response relation was observed when insulin-to-glucose ratio or homeostatic model assessment of insulin resistance was used as exposure.

CONCLUSIONS

Fasting serum insulin levels or hyperinsulinemia in young adulthood was positively associated with incidence of HTN later in life for both men and women, African Americans and Caucasians, and those with normal weight and overweight. Our findings suggested that fasting insulin ascertainment may help clinicians identify those at high risk of HTN.

Fatness, fitness, and cardiometabolic risk factors in middle-aged white men

The objective was to test the hypothesis that traditional and novel cardiometabolic risk factors would be significantly different in groups of men of different fatness and fitness. Total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglycerides, glucose, insulin, high-sensitivity C-reactive protein, alanine aminotransferase, aspartate aminotransferase, γ-glutamyltransferase, leptin, adiponectin, tumor necrosis factor-α, interleukin-6, interleukin-10, fibrinogen, and insulin resistance were assessed in 183 nonsmoking white men aged 35 to 53 years, including 62 who were slim and fit (waist girth ≤90 cm and maximal oxygen consumption [VO(2)max] above average), 24 who were slim and unfit (waist girth ≤90 cm and VO(2)max average or below), 39 who were fat and fit (waist girth ≥100 cm and VO(2)max above average), and 19 who were fat and unfit (waist girth ≥100 cm and VO(2)max average or below). Seventy-six percent gave blood on 2 occasions, and the average of 1 or 2 blood tests was used in statistical tests. Waist girth (centimeters) and fitness (milliliters of oxygen per kilogram of fat-free mass) were associated with high-density lipoprotein cholesterol, leptin, and insulin resistance after adjustment for age, saturated fat intake, and total energy intake. High-density lipoprotein cholesterol, triglycerides, alanine aminotransferase, and insulin resistance were significantly different in men who were fat and fit and those who were fat and unfit. These data suggest that differences in lipid and lipoprotein concentrations, liver function, and insulin resistance may explain why the risks of chronic disease are lower in men who are fat and fit than those who are fat and unfit.

Insulin resistance and risk of incident hypertension among men

J Clin Hypertens (Greenwich). 2009;11:483-490. (c) 2009 Wiley Periodicals, Inc.The independent association between insulin resistance and the development of hypertension remains in doubt because insulin resistance correlates with other metabolic factors also proposed to be associated with hypertension. The authors examined the association between the insulin sensitivity index and incident hypertension in a prospective nested case-control study among 1453 men (mean age, 61 years) who participated in the Health Professionals' Follow-up Study. The authors computed the insulin sensitivity index for each man in the study based on fasting insulin and triglyceride levels. Logistic regression was performed conditioned on age and adjusted for standard hypertension risk factors as well as renal function, cholesterol, and uric acid. The insulin sensitivity index was 6% lower in the cases compared with the controls (P<.001). The multivariable odds ratio for hypertension comparing the lowest with highest quartile of insulin sensitivity index was 1.09 (0.71-1.65) among the entire sample. However, the association between the insulin sensitivity index and incident hypertension differed significantly by age (P interaction <.001). Among men younger than 60 years, the multivariable odds ratio for the lowest compared with highest quartile was 1.93 (1.01-3.71) but was 0.67 (0.37-1.24) among older men. Insulin resistance is independently associated with incident hypertension among younger men.

The insulin gradient phenomenon: a manifestation of the effects of body weight on blood pressure and insulin resistance

The relationship between hyperinsulinemia and hypertension is frequently observed in overweight patients; however, population studies have not confirmed an independent association. A population study was conducted to assess whether differences in body mass index and levels of insulinemia modify cardiovascular hemodynamics and arterial pressure. In all, 322 healthy adults underwent a medical evaluation including insulin sensitivity and cardiac performance assessment with echocardiography. A direct relationship between body mass index and blood pressure (r=0.36; P<.01) was shown along with increments in fasting insulin levels. The underlying and progressive rise in insulin levels during blood pressure increase is named the insulin gradient. Left ventricular systolic indexes were significantly greater in the higher-insulin quartile. These findings suggest that body weight increases accompany a rise in systolic pressure and a drop in insulin sensitivity related to the insulin gradient. Increments in ejection fraction and cardiac output with normal total peripheral resistance are related to the blood pressure shift in these persons.

Uric acid and insulin sensitivity and risk of incident hypertension

BACKGROUND

Uric acid, insulin sensitivity, and endothelial dysfunction may be important in the development of hypertension. Corresponding circulating biomarkers are associated with risk of hypertension, but because these factors may be interrelated, whether they independently affect risk is unknown.

METHODS

In 1496 women aged 32 to 52 years without hypertension at baseline, we prospectively analyzed the associations between fasting plasma levels of uric acid, insulin, triglycerides, the insulin sensitivity index, and 2 biomarkers associated with endothelial dysfunction (homocysteine and soluble intercellular adhesion molecule-1) and the odds of incident hypertension. Odds ratios were adjusted for standard risk factors and then for all biomarkers plus estimated glomerular filtration rate and total cholesterol level. Population-attributable risk was estimated for biomarkers significantly associated with hypertension.

RESULTS

All the biomarkers were associated with incident hypertension after adjustment for standard hypertension risk factors. However, after simultaneously controlling for all the biomarkers, estimated glomerular filtration rate, and total cholesterol level, only uric acid and insulin levels were independently associated with incident hypertension. Comparing the highest and lowest quartiles of uric acid levels, the odds ratio was 1.89 (95% confidence interval, 1.26-2.82). A similar comparison yielded an odds ratio of 2.03 (95% confidence interval, 1.35-3.05) for insulin levels. Using an estimated basal incidence rate of 14.6 per 1000 annually, 30.8% of all hypertension occurring in young women annually is associated with uric acid levels of 3.4 mg/dL or greater (to convert to micromoles per liter, multiply by 59.485). For insulin levels of 2.9 microIU/mL or greater (to convert to picomoles per liter, multiply by 6.945), this proportion is 24.2%.

CONCLUSIONS

Differences in uric acid and insulin levels robustly and substantially affect the risk of hypertension in young women. Measuring these biomarkers in clinical practice may identify higher-risk individuals.

Central obesity as a precursor to the metabolic syndrome in the AusDiab study and Mauritius

Evidence from epidemiologic studies that central obesity precedes future metabolic change and does not occur concurrently with the appearance of the blood pressure, glucose, and lipid abnormalities that characterize the metabolic syndrome (MetS) has been lacking. Longitudinal surveys were conducted in Mauritius in 1987, 1992, and 1998, and in Australia in 2000 and 2005 (AusDiab). This analysis included men and women (aged > or = 25 years) in three cohorts: AusDiab 2000-2005 (n = 5,039), Mauritius 1987-1992 (n = 2,849), and Mauritius 1987-1998 (n = 1,999). MetS components included waist circumference, systolic blood pressure, fasting and 2-h postload plasma glucose, high-density lipoprotein (HDL) cholesterol, triglycerides, and homeostasis model assessment of insulin sensitivity (HOMA-S) (representing insulin sensitivity). Linear regression was used to determine which baseline components predicted deterioration in other MetS components over 5 years in AusDiab and 5 and 11 years in Mauritius, adjusted for age, sex, and ethnic group. Baseline waist circumference predicted deterioration (P < 0.01) in four of the other six MetS variables tested in AusDiab, five of six in Mauritius 1987-1992, and four of six in Mauritius 1987-1998. In contrast, an increase in waist circumference between baseline and follow-up was only predicted by insulin sensitivity (HOMA-S) at baseline, and only in one of the three cohorts. These results suggest that central obesity plays a central role in the development of the MetS and appears to precede the appearance of the other MetS components.

In-Treatment Resolution or Absence of Electrocardiographic Left Ventricular Hypertrophy Is Associated With Decreased Incidence of New-Onset Diabetes Mellitus in Hypertensive Patients

Treatment of hypertensive patients with electrocardiographic left ventricular hypertrophy with losartan-based therapy is associated with lower incidence of diabetes mellitus and greater regression of hypertrophy than atenolol-based therapy. However, whether in-treatment resolution or continued absence of electrocardiographic hypertrophy is independently associated with decreased incidence of diabetes is unclear. Electrocardiographic hypertrophy was evaluated over time in 7998 hypertensive patients without diabetes at baseline in the Losartan Intervention For Endpoint reduction in hypertension (LIFE) study who were treated with losartan- or atenolol-based regimens and followed with serial electrocardiograms and blood pressure determinations. Electrocardiographic hypertrophy was defined using gender-adjusted Cornell voltage-duration product criteria >2440 mm·ms. During mean follow-up of 4.6±1.2 years, diabetes developed in 562 patients (7.0%). In a Cox model adjusting for treatment assignment, in-treatment resolution or continued absence of Cornell product hypertrophy was associated with a 38% lower risk of new diabetes (HR 0.62, 95% CI 0.50 to 0.78). After adjusting for the association of new diabetes with prior antihypertensive treatment, baseline glucose, and Framingham risk score, baseline and in-treatment systolic and diastolic pressure, HDL, uric acid, and body mass index, and the decreased incidence associated with losartan-based therapy, in-treatment continued absence, or resolution of Cornell product hypertrophy remained associated with a 26% lower risk of new diabetes (HR 0.74, 95% CI 0.58 to 0.93). Thus, compared with presence of hypertrophy by Cornell product criteria during antihypertensive treatment, resolution or continued absence of Cornell product hypertrophy is associated with a lower incidence of diabetes, even after adjusting for the impact of treatment with losartan and other risk factors for diabetes.

The metabolic syndrome: metabolic changes with vascular consequences

Despite criticism regarding its clinical relevance, the concept of the metabolic syndrome improves our understanding of both the pathophysiology of insulin resistance and its associated metabolic changes and vascular consequences. Free fatty acids (FFA) and tumour necrosis factor-alpha (TNF-alpha) play prominent roles in the development of insulin resistance by impairing the intracellular insulin signalling transduction pathway. Obesity is an independent risk factor for cardiovascular disease and strongly related to insulin resistance. In case of obesity, FFAs and TNF-alpha are produced in abundance by adipocytes, whereas the production of adiponectin, an anti-inflammatory adipokine, is reduced. This imbalanced production of pro- and anti-inflammatory adipokines, as observed in adipocyte dysfunction, is thought to be the driving force behind insulin resistance. The role of several recently discovered adipokines such as resistin, visfatin and retinol-binding protein (RBP)-4 in the pathogenesis of insulin resistance is increasingly understood. Insulin resistance induces several metabolic changes, including hyperglycaemia, dyslipidaemia and hypertension, all leading to increased cardiovascular risk. In addition, the dysfunctional adipocyte, reflected largely by low adiponectin levels and a high TNF-alpha concentration, directly influences the vascular endothelium, causing endothelial dysfunction and atherosclerosis. Adipocyte dysfunction could therefore be regarded as the common antecedent of both insulin resistance and atherosclerosis and functions as the link between obesity and cardiovascular disease. Targeting the dysfunctional adipocyte may reduce the risk for both cardiovascular disease and the development of type 2 diabetes. Although lifestyle intervention remains the cornerstone of therapy in improving insulin sensitivity and its associated metabolic changes, medical treatment might prove to be important as well.