Joint effects of age and body mass index on the incidence of hypertension subtypes in the China Health and Nutrition Survey: A cohort study over 22years

Prevalence, awareness, and treatment of isolated diastolic hypertension in the United States

BACKGROUND

Isolated diastolic hypertension (IDH) is recognized as a risk factor for cardiovascular disease, yet its clinical epidemiology remains poorly understood due to insufficient recognition. This study aims to describe the trend in the prevalence, awareness, and treatment of IDH in the United States from 2001 to 2018.

METHODS

This cross-sectional study utilized data from the National Health and Nutrition Examination Survey (NHANES) conducted in nine consecutive two-year cycles from 2001-2002 to 2017-2018, comprising a sample of 48,742 adults aged over 18 years. IDH was defined as a diastolic blood pressure ≥ 80 mm Hg with a systolic BP < 130 mm Hg by the 2017 American College of Cardiology (ACC)/American Heart Association (AHA) guidelines.

RESULTS

In the nationally representative dataset, 8.9% of participants had IDH in 2017-2018, a decreased of 3.6% (95% confidence interval [CI], -2.6% to -5.0%, P<0.0002) since 2001-2002. IDH prevalence was highest among Mexican American (10.5%), individuals aged 40-59 (12.3%), increased with body mass index (BMI) (11.2% among those BMI ≥30.0 kg/m2), and tended to be higher in men (12.3%). A multiple regression analysis showed that men, white race/ethnicity, young and middle-aged people (aged 18-59), and increasing BMI were independently associated with increased risks of IDH. Among IDH patients, there was a modest increase in awareness (P<0.0002), from 22.4% (95%CI, 18.4% to 27.1%) in 2001-2002 to 35.0% (95%CI, 28.2% to 42.5%) in 2017-2018, with the largest percentage increases among non-Hispanic white and men. IDH treatment increased by 7.6% (95%CI, 3.1% to 12.1%) between 2001-2002 and 2017-2018, with the greatest increases occurring in Mexican American and men.

CONCLUSION

IDH prevalence is decreasing from 2001-2002 to 2017-2018 in the United States. Despite the significantly increased in both awareness and treatment, they remain below 50%.

Associations of Carbohydrate Intake With New-Onset Hypertension Subtypes: Results From the China Health and Nutrition Survey (2000-2011)

Background: The effects of carbohydrate intake on hypertension (HTN) subtypes are scarce. We examined the association of carbohydrate intake with new-onset HTN subtypes in Chinese adults. Methods: Chinese Health and Nutrition Survey (CHNS) 2000-2011, 22,418 individuals were recorded using a 24-h recall method over three consecutive days. We excluded those who were pregnant women, lactating mothers, age <18 years, baseline age, blood pressure, and energy intake deficiency, extreme energy intake (male > 6,000 kcal or < 800 kcal; female > 4,000 kcal or < 600 kcal), and pulse pressure difference (Systolic Blood Pressure [SBP] - Diastolic Blood Pressure [DBP]) <10 mm Hg, HTN at baseline and data from only one survey. The total number of subjects who participated in at least two surveys was 7,930. The main outcome was new-onset HTN subtypes over 6.9 person years of follow-up. Results: 2,521 participants were found to be HTN, which included 1,318 males (52.3%), 1,203 females (47.7%), 721 had systolic-diastolic hypertension (SDH, 28.6%), 655 had isolated systolic hypertension (ISH, 26.0%), and 993 had isolated diastolic hypertension (IDH, 39.4%). Compared with extreme quintiles of carbohydrate, multivariable-adjusted hazard ratios (HR) and 95% confidence intervals (CI) for new-onset HTN, SDH, ISH and IDH associated with carbohydrate intake were 1.12 (0.97-1.30), 1.54 (1.18-2.00), 0.89 (0.67-1.19) and 1.15 (0.91-1.45), respectively. The HR of SDH compared with extreme quintiles of carbohydrates was 1.56 (95% CI, 1.08-2.25; P trend = 0.04) in men and 1.52 (95% CI, 1.02-2.26; P trend = 0.02) in women. Conclusion: Carbohydrates were related to a higher risk of SDH, which were not observed with HTN, ISH, and IDH.

Interaction of sex, age, body mass index and race on hypertension risk in the American population: a cross-sectional study

BACKGROUND

The joint effects of sex, age, body mass index (BMI) and race on hypertension have not been fully addressed. Herein, we carried out this study aiming to investigate the possible effects of the interaction of sex, age, BMI and race on risk of hypertension.

METHODS

By using the data of a sample-adjusted 2656 women and 2515 men in American National Health and Nutrition Examination Survey 2015-16, we analyzed the interaction of sex, age, BMI and race by logistic regression models, followed by strata-specific analyses. Hypertension was defined as a systolic blood pressure ≥130 mmHg/diastolic blood pressure ≥80 mmHg or taking anti-hypertensive medication.

RESULTS

A total of 5171 participants were included in analysis, and the prevalence of hypertension was 53.68%. The interactive effect of sex and age, BMI and age, race and age were statistically significant on hypertension. Strata-specific analyses showed that female at 40 years and above were positively associated with hypertension than those at 20-39 years. The associations also persistence in male. The risk estimates for age ≥40 on hypertension were consistently positive across all overweight/obesity and race groups. The effect was most prominent among overweight populations aged 60-80 years and Other Hispanic aged 40 years and above.

CONCLUSION

There exists interactive effect of sex and age, BMI and age, race and age on hypertension in American population. The effect of age on hypertension was more prominent in female, overweight populations and Other Hispanic populations. Differences in age, BMI and race should be considered when providing corresponding antihypertensive measures.

The Rates and the Determinants of Hypertension According to the 2017 Definition of Hypertension by ACC/AHA and 2014 Evidence-Based Guidelines Among Population Aged ≥40 Years Old

Background:

In November 2017, the American College of Cardiology/American Heart Association (ACC/AHA) updated their definition of hypertension from 140/90 mm Hg to 130/80 mm Hg.

Objectives:

We sought to assess the situation of hypertension and the impact of applying the new threshold to a geographically and ethnically diverse population.

Methods:

We analyzed selected data on 237,142 participants aged ≥40 who had blood pressure taken for the 2014 China National Stroke Screening and Prevention Project. Choropleth maps and logistic regression analyses were performed to estimate the prevalence, geographical distribution and risk factors of hypertension using both 2017 ACC/AHA guidelines and 2014 evidence-based guidelines.

Results:

The present cross-sectional study showed the age- and sex-standardized prevalence of hypertension was 37.08% and 58.52%, respectively, according to 2014 evidence-based guidelines and 2017 ACC/AHA guidelines. The distribution of hypertension and risk factors changed little between guidelines, with data showing a high prevalence of hypertension around Bohai Gulf and in south central coastal areas using either definition. The age- and sex-standardized prevalence of newly labeled as hypertensive was 21.44%. Interestingly, the high prevalence region of newly labeled as hypertensive was found in the north China.

Conclusion:

The prevalence of hypertension increased significantly on 2017 ACC/AHA guidelines compared to the prevalence when using 2014 evidence-based guidelines, with high prevalence areas of newly labeled as hypertensive now seen mainly in north China. There need to be correspondingly robust efforts to improve health education, health management, and behavioral and lifestyle interventions in the north.

Secular trends of population attributable risk of overweight and obesity for hypertension among Chinese adults from 1991 to 2011

We determined if the increasing trend in hypertension can be partly attributed to increasing prevalence of overweight/obesity in China over the past two decades. Data were collected from 1991 to 2011 and the population attributable risk (PAR), which is used to estimate the intervention effect on hypertension if overweight/obese, were eliminated. Linear regression was used to evaluate the secular trends. The age-standardized prevalence of overweight and obesity increased by 26.32% with an overall slope of 1.27% (95% CI: 1.12–1.43%) per year. Hypertension also increased by 12.37% with an overall slope of 0.65% (95% CI: 0.51–0.79%) per year. The adjusted ORs of overweight/obesity for hypertension across the survey years remained unchanged; however, the trend in PAR increased steadily from 27.1 to 44.6% with an overall slope of 0.81% (95% CI: 0.34–1.28%) per year (P = 0.006). There was no significant gender difference in the slopes of increasing PAR, as measured by regression coefficients (β = 0.95% vs. β = 0.63% per year, P = 0.36). Over the past two decades, the increase in the prevalence of hypertension in China was partly attributed to the overweight/obesity epidemic, which highlights the importance of controlling weight and further reducing the burden of hypertension.

The association between longitudinal trends of thyroid hormones levels and incident hypertension in a euthyroid population

Thyroid hormones, including free triiodothyronine (FT3), free thyroxine (FT4), have well-recognized effects on the cardiovascular system. However, the evidence is lacking regarding the relationship between repeated FT3, FT4, and thyroid-stimulating hormone (TSH) measurements and incident hypertension. The aim of this cohort study was to examine how longitudinal trends of serum FT3, FT4, and TSH levels are related to the development of hypertension in a euthyroid population. A prospective study (n = 5926) was performed in Tianjin, China. Participants without a history of hypertension were followed up for ~4 years (median: 3 years). Hypertension was defined according to the criteria of JNC7. FT3, FT4, and TSH were determined by chemiluminescence immunoassay methods. FT3, FT4, TSH, and blood pressure were assessed yearly during follow-up. Adjusted Cox proportional hazards regression models were used to assess the relationships between baseline, means, and annual changes in FT3, FT4, TSH, and hypertension. The incidence rate of hypertension per 1000 person-years was 73. Compared with the lowest quartile, the multivariable-adjusted hazards ratios (95% confidence interval) for hypertension in the highest quartiles of changes in FT3, FT4, and TSH were 1.51 (1.23-1.84), 2.04 (1.67-2.48), and 1.20 (0.99-1.45), respectively. Similar relationships were observed between the means of FT3, FT4, TSH, and hypertension. However, we found no correlations between baseline FT3, FT4, TSH, and incident hypertension. The present study is the first to demonstrate that the annual changes and means, but not baseline FT3 and FT4 values are independently related to the risk of incident hypertension in the euthyroid general population.

Long-term trends and regional variations of hypertension incidence in China: a prospective cohort study from the China Health and Nutrition Survey, 1991-2015

OBJECTIVE

The aim is to explore the trends of hypertension incidence and regional variations in China from 1991 to 2015.

DESIGN

A dynamic prospective cohort study.

SETTING

China Health and Nutrition Survey 1991-2015.

PARTICIPANTS

12 952 Chinese adults aged 18+ years.

PRIMARY OUTCOME MEASURES

Incident hypertension from 1993 to 2015.

RESULTS

Age-standardised hypertension incidence increased from 40.8 per 1000 person-years (95% CI 38.3 to 43.4) between 1993 and 1997 to 48.6 (95% CI 46.1 to 51.0) between 2011 and 2015. The increasing trends were further supported by results from subsequent extended Cox proportional hazard model. In addition, results from the modelling analysis showed that individuals in eastern, central and northeastern China had greater risks of hypertension occurrence in comparison with their counterparts in western China.

CONCLUSION

Hypertension incidence increased during the study period. The growth called for more attention on the health education and health promotion of individuals with great risks.

The Roles of Genetic and Early-Life Environmental Factors in the Association Between Overweight or Obesity and Hypertension: A Population-Based Twin Study

AIMS/HYPOTHESIS

We aimed to explore whether and to what extent overweight or obesity could increase the risk of hypertension, and further to estimate the roles of genetic and early-life familial environmental factors in their association.

METHODS

This prospective twin study was based on the Chinese National Twin Registry (CNTR), which collected information from self-report questionnaires. We conducted unmatched case-control analysis to examine the association between overweight or obesity and hypertension. And further to explore whether genetics and familiar environments shared within a twin pair, accounted for their association via co-twin matched case-control design. Generalized estimating equation (GEE) models and conditional logistic regressions were used in the unmatched and matched analyses, respectively. Then, we used logistic regressions to test the difference in odds ratios (ORs) between the unmatched and matched analyses. Finally, through bivariate twin model, the roles of genetic and environmental factors in the body mass index (BMI)- hypertension association were estimated.

RESULTS

Overall, we included a total of 30,617 twin individuals, of which 7533 (24.6%) twin participants were overweight or obesity and 757 (2.5%) developed hypertension during a median follow-up time of 4.4 years. In the GEE model, overweight or obesity was associated with a 94% increased risk of hypertension (OR=1.94, 95% confidence interval (CI): 1.64~2.30). In the conditional logistic regression, the multi-adjusted OR was 1.80 (95% CI: 1.18~2.74). The difference in OR between unmatched and matched analyses was significant (P=0.016). Specifically, overweight or obesity was not associated with hypertension risk in the co-twin design when we full controlled genetic and familiar environmental factors (OR=0.89, 95 CI: 0.46~1.72). After controlling for age and sex, we found the positive BMI-hypertension association was mainly explained by a genetic correlation between them (r_A= 0.59, 95% CI: 0.44~1.00).

CONCLUSIONS/INTERPRETATION

Genetics and early-life environments shared by participants within a twin pair appear to account for the association between overweight or obesity and hypertension risk.

Gender-specific temporal trends in overweight prevalence among Chinese adults: a hierarchical age-period-cohort analysis from 2008 to 2015

Background

As a key health risk, the prevalence of overweight has been strikingly increasing worldwide. This study aimed to disentangle the net age, period, and cohort effects on overweight among Chinese adults by gender.

Methods

Data came from the Chinese General Social Survey from 2008 to 2015, which was a repeated cross-sectional survey (n = 55,726, aged 18 and older). χ² or t tests were used to estimate the gender disparities in overweight and socioeconomic status (SES). A series of hierarchical age-period-cohort cross-classified random-effects models were performed using SAS version 9.4 to estimate the overall and gender-specific temporal trends of overweight, as well as the association between SES and overweight. Further, a series of line charts were used to present the age and cohort variations in overweight.

Results

After controlling for covariates, significant age and cohort effects were observed among adults in China (b = 0.0205, p < 0.001; b = 0.0122, p < 0.05; respectively). Specifically, inverted U-shaped age effects were identified for both genders, with a high probability of overweight occurring in middle age (b = -0.0012, p < 0.001). Overweight was more prevalent among men than women before 60 years old, and this trend reversed thereafter (b = -0.0253, p < 0.001). Moreover, men born during the war (before 1950) and reform cohorts (after the 1975s) demonstrated a substantial decline in overweight, while men born in 1950-1975 showed an increasing trend in overweight prevalence (b = 0.0378, p < 0.05). However, the cohort effect on women was not statistically significant. Additionally, a higher SES was related to an elevated probability of overweight.

Conclusion

Gender-specific age and cohort effects on the prevalence of overweight were observed among Chinese adults. Both China and other developing countries need to pay attention to the coming obesity challenge and related health inequality. Full life-cycle overweight prevention interventions should focus on middle-aged adults, men born in the war and reform eras, and adults with a higher SES.

Association between body mass index and hypertension subtypes in Indian and United States adults

The purpose of this cross-sectional, secondary analysis was to determine the association between BMI & lipids and hypertension subtype in U.S. and Indian adults. Obese BMI was significantly associated with isolated diastolic hypertension (IDH) compared to low/normal BMI (relative risk ratio [95% CI]; U.S.: 4.33 [2.88,6.52]; India: 2.51 [2.41,2.60]). Furthermore, BMI was more strongly associated with IDH than other hypertension subtypes in U.S. and non-obese Indian adults. In obese Indian adults, we observed higher odds of isolated systolic hypertension until the 6th decade, and systo-diastolic hypertension thereafter. Triglyceride levels were associated with IDH in U.S. adults (1.94 [1.43,2.63]).

The Impact of Hypertension Definition Based on Two-visit Strategy on Estimate of Hypertension Burden: Results From the China Health and Nutrition Survey 1989-2011

Background

The diagnosis of hypertension should be based on the mean of two or more properly measured BP readings on each of two visits for clinical practice, but a one-visit strategy was applied in most epidemiological surveys. The impact of hypertension definition based on two visits on estimates of hypertension burden is unknown. This study aims to assess the impact of hypertension diagnosis based on a two-visit strategy for estimating hypertension burden in China.

Methods

The one-visit and two-visit strategies were applied to investigate the incidence of hypertension in a cohort study based on the China Health and Nutrition Survey (CHNS) 1989–2011. Additionally the prevalence of hypertension was investigated in a cross-sectional study based on the CHNS 2006–2009/2011 and the hypertension burden in China was estimated with data from the 2012–2015 China hypertension survey.

Results

Overall, the age-adjusted incidence of hypertension based on the two-visit strategy (1.82%; 95% confidence interval [CI], 1.74–1.90%) was 62.1% lower than estimation based on the one-visit strategy (4.80%; 95% CI, 4.68–4.93%). Similar results were found in the prevalence of hypertension (one-visit: 18.13% [95% CI, 17.34–18.92%]; two-visit: 9.47% [95% CI, 8.87–10.07%]). When the two-visit strategy was applied to the 2012–2015 China hypertension survey, the hypertension burden was predicted to be overestimated by 25.5–47.8% (based on JNC 7) and 23.5–48.2% (based on the 2017 ACC/AHA).

Conclusion

The hypertension burden would decrease from 244.5 million persons to 127.5–182.3 million persons in China if the two-visit strategy was applied.

Joint Effects of Body Mass Index and Waist Circumference on the Incidence of Hypertension in a Community-Based Chinese Population

OBJECTIVE

We aimed to investigate the relationships of body mass index (BMI), waist circumference (WC), and obesity defined using a combination of both indexes, with the incidence of hypertension in a Chinese community-based population.

METHODS

A total of 1,927 Chinese participants (57.2 ± 8.9 years old) with normal blood pressure at baseline were recruited from the Shijingshan community in Beijing. Incident hypertension was defined as blood pressure ≥140/90 mm Hg, self-reported hypertension, or the use of any antihypertensive medication at the follow-up visit.

RESULTS

During 2.3 years of follow-up, 19.1% (n = 97) of the men and 13.6% (n = 158) of the women developed incident hypertension. The adjusted odds ratios (ORs) (95% confidence intervals [CIs]) for obesity (BMI ≥30) were 3.49 (1.59-7.66) and 2.60 (1.48-4.55) for men and women, respectively. A 1-point increase in BMI was associated with 8% (OR = 1.08, 95% CI: 1.00-1.17) and 10% (OR = 1.10, 95% CI: 1.05-1.16) increases in the incidence of hypertension in men and women, respectively. Abdominal obesity (WC ≥90 cm in men and ≥85 cm in women) was positively associated with incident hypertension in both men (adjusted OR = 1.79, 95% CI: 1.10-2.91) and women (adjusted OR = 1.61, 95% CI: 1.09-2.40). A 1-cm increase in WC was associated with 4% (adjusted OR = 1.04, 95% CI: 1.01-1.07) and 4% (adjusted OR = 1.04, 95% CI: 1.02-1.07) increases in the incidence of hypertension in men and women, respectively. The combination of abnormal BMI and WC has the highest risk for hypertension in both men (adjusted OR = 3.10, 95% CI: 1.48-6.50) and women (adjusted OR = 2.51, 95% CI: 1.43-4.40).

CONCLUSIONS

This study shows that BMI, WC, and an index that combined the two are independently associated with incident hypertension in a Chinese community-based population.

Primary prevention of cardiovascular disease in older adults in China

Over the past two decades, the percentage of Chinese who is 60 years or older has increased from 5.2% in 1995 to 10.5% in 2015. Approximately 16% of the population in China was 60 years old and above in 2015. Since 1990, cardiovascular disease (CVD) has been the leading cause of death in China. Cardiovascular medications of older adults are usually more complicated than younger age groups due to polypharmacy, the presence of comorbidities and more susceptible to treatment-related adverse outcomes. Therefore, effective primary prevention of CVD for older adults is important in sustaining the health of older adults and reducing the burden of the healthcare system. Proper management of CVD-related risk factors, such as hypertension, dyslipidemia, diabetes and obesity, can remarkably reduce risks of CVDs in older Chinese. These risk factors can be modified by managing blood pressure, glucose and lipids via lifestyle modifications or receiving medications. Smoking cessation, healthy diets, strict alcohol intake and moderate physical exercise are examples of recommended lifestyle changes for remarkably recovering health conditions of older adults who have hypertension, dyslipidemia, obesity, diabetes or complications. Treatment prescriptions of older adults, in general, are recommended to be individualized and to be initiated at a low dose. The future directions for better primary CVD prevention in older adults include establishing guidelines for primary prevention of CVD for different older adults and further research on better management strategies of CVD risks for elderly Chinese.