Long-term stable obesity increases risk of hypertension

Body Mass Index Measured Repeatedly over 42 Years as a Risk Factor for Ischemic Stroke: The HUNT Study

BACKGROUND

Higher BMI in middle age is associated with ischemic stroke, but little is known about BMI over adulthood, and the risk for ischemic stroke as most studies relied on a single measurement of BMI.

METHODS

BMI was measured four times over a period of 42 years. We calculated average BMI values and group-based trajectory models and related these to the prospective risk of ischemic stroke after the last examination in Cox models with a follow-up time of 12 years.

RESULTS

A total of 14,139 participants, with a mean age of 65.2 years and 55.4% women, had information on BMI from all four examinations, and we observed 856 ischemic strokes. People with overweight and obesity over adulthood had a higher risk for ischemic stroke with a multivariable-adjusted hazard ratio of 1.29 (95% CI 1.11-1.48) and 1.27 (95% CI 0.96-1.67), respectively, when compared to normal weight participants. Excess weight tended to have stronger effects earlier than later in life. A trajectory of developing obesity throughout life was associated with higher risk than other trajectories.

CONCLUSIONS

High average BMI, especially at an early age, is a risk factor for ischemic stroke. Early weight control and long-term weight reduction for those with high BMI may decrease the later occurrence of ischemic stroke.

Sleep Duration and Visceral Adipose Tissue: Linear and Nonlinear Mendelian Randomization Analyses

CONTEXT

Increasing evidence suggests that sleep is important for fat metabolism. However, the causal relationship between sleep duration and visceral adipose tissue (VAT) needs to be further clarified.

OBJECTIVE

This study investigated the linear and nonlinear causal association between sleep duration and VAT.

METHODS

This study used one-sample and two-sample Mendelian randomization MR). Single-nucleotide polymorphisms (SNPs) associated with sleep duration at genome-wide significance were obtained from published genome-wide association studies. We also recalculated the correlation between each SNP and sleep duration in the UK Biobank. The associations of SNPs with predicted VAT (396 858 participants) were conducted in the UK Biobank.

RESULTS

A total of 396 858 eligible participants (54.10% females, 57 ± 8 years old) were included in the study. The participants slept 7.17 ± 1.04 hours and stored 1.25 ± 0.88 kg of VAT on average. Genetically predicted sleep duration was significantly associated with VAT. For each 1-hour increase in genetically predicted sleep duration, the reduction in predicted VAT mass was 0.11 kg (P = 8.18E-16) in total, 0.17 kg (P = 3.30E-11) in men and 0.07 kg (P = 1.94E-06) in women. Nonlinear MR analyses demonstrated nonlinearity (L-shaped associations) between genetically predicted sleep duration and VAT in all participants, men, and women. Complementary analyses provided confirmative evidence of the adverse effects of genetically predicted short sleep duration on the increased VAT. In contrast, no clear evidence on the causal effect of genetically predicted long sleep duration on VAT mass was found.

CONCLUSION

The causal association of sleep duration with VAT was L-type. Our findings support that short sleep duration is a risk factor for increasing VAT, thus reinforcing the probability that increasing sleep duration may decrease VAT.

Temporal Associations between Tri-Ponderal Mass Index and Blood Pressure in Chinese Children: A Cross-Lag Analysis

Background: No longitudinal studies have explored the relationship between tri-ponderal mass index (TMI) and blood pressure (BP) in children. This study is aimed to investigate the temporal associations between TMI and BP among children in China. Methods: A longitudinal study was carried out with Chinese children from 2014 to 2019. Data of the anthropometric examination and blood pressure were collected annually. TMI was calculated by dividing weight by the cube of height. BP was measured using a standard mercury sphygmomanometer. We investigated temporal associations between TMI and BP with a cross-lagged panel model using repeated measure data from 2014 (Wave 1), 2016 (Wave 2), and 2018 (Wave 3). Results: Results of the cross-lagged panel model showed that TMI was associated with subsequent BP. Participants with higher levels of TMI presented higher levels of BP (Wave 1: β = 0.737 for systolic blood pressure (SBP) and β = 0.308 for diastolic blood pressure (DBP), Wave 2: β = 0.422 for SBP and β = 0.165 for DBP, p < 0.01). In addition, children with higher BP could also present higher TMI (Wave 1: β = 0.004 for SBP and β = 0.006 for DBP, Wave 2: β = 0.003 for SBP and β = 0.005 for DBP, p < 0.01), but the cross-lag path coefficient indicated that the influence of TMI on BP was stronger than the influence of BP on TMI. Conclusions: There was a temporal association between TMI and BP in Chinese children. Higher TMI predicted higher subsequent BP rather than the reverse relationship.

Trajectories of mid-life to elderly adulthood BMI and incident hypertension: the China Health and Nutrition Survey

OBJECTIVES

This study is designed to identify different body mass index (BMI) trajectories of individuals aged 40-70 years and test the effect of distinct BMI trajectories on incident hypertension.

DESIGN

The accelerated longitudinal design was used for this study.

METHODS

The study drew data from the third to ninth China Health and Nutrition Surveys (CHNS), and 4697 participants were included between 1991 and 2015. As analysed, three distinct individual BMI trajectories were identified by the latent class growth mixed model (LCGMM). Then, BMI values and BMI slopes were worked out through calculation with LCGMM trajectory parameters and their primary derivatives, respectively. Later, Cox proportional hazard models were applied to examine BMI values and slopes, and find out the relationship between the said predicted data and incident hypertension for different classes.

RESULTS

Three different trajectory classes were identified, that is, low-stable class (n=3711), sharp-increasing class (n=282) and high-stable class (n=704). Compared with the low-stable class, the adjusted HRs (95% CI) were 1.321 (1.119 to 1.559) and 1.504 (1.322 to 1.711) for the sharp-increasing class and the high-stable class, respectively. The HR (95% CI) for BMI values rose from 1.081 (1.030 to 1.135) to 1.221 (1.171 to 1.273) while the HR (95% CI) for BMI slopes dropped from 1.154 (1.100 to 1.211) to 0.983 (0.943 to 1.025). That is, the HR for BMI slopes were higher than that for BMI values for the class aged 40-47 years.

CONCLUSION

These findings suggest that the calibrated BMI trajectories for the period from mid-life to elderly adulthood have a significant effect on the risk of incident hypertension. The period from age 40 to 47 years is critical and has positive implications for the early prevention of hypertension.

Influence of Changes in Obesity Indicators on the Risk of Hypertension: A Cohort Study in Southern China

OBJECTIVES

The objective of this study was to demonstrate the association between changes in different obesity indicators and the risk of incident hypertension by the age-group among community-dwelling residents in southern China.

METHODS

A total of 6,959 non-hypertensive participants aged ≥18 years old were enrolled in this cohort study and completed questionnaire interviews and anthropometric measurements at baseline (2010) and follow-up (2017). A time-dependent covariate Cox proportional hazard model considered the changes in obesity indicators during the follow-up period and calculated the hazard ratios (HRs) to analyze the risk of incident hypertension according to different obesity indicators.

RESULTS

During a mean follow-up of 7.1 years, 1,904 participants were newly diagnosed with hypertension. The body mass index (BMI), waist circumference (WC), waist-to-hip ratio (WHR), and waist-to-height ratio (WHtR) were significantly positively associated with an increased future risk of incident hypertension, and BMI was the best predictive indicator of hypertension (obesity in men: HR = 2.65, 95% confidence interval (CI) = 2.20-3.20; obesity in women: HR = 2.80, 95% CI = 2.27-3.45). Compared with the middle-aged and older group, the risk of incident hypertension was highest in the younger group which had the highest baseline obesity indicators.

CONCLUSIONS

Changes in obesity indicators were significantly associated with the risk of incident hypertension in all age-groups, and the risk of future incident hypertension increased with the increase in baseline obesity indicators.

Gestational Hypertension as Risk Factor of Hypertension in Middle-Aged and Older Women

The association of gestational hypertension (GH) with future hypertension in Japanese women is unclear. Hence, this study aimed to examine the association between GH and the risk of future hypertension in middle-aged-to-older Japanese women. A case-control study was performed, including 62 hypertensive women (case) and 75 nonhypertensive women (control). GH during the first pregnancy was diagnosed on the basis of the Maternal and Child Health Handbook record. Hypertensive women were recruited from outpatients in the hospital and residents who completed an annual health check-up in a community. Hypertension was defined as blood pressure with systolic blood pressure ≥140 mmHg and/or diastolic blood pressure ≥90 mmHg, or taking antihypertensive medications. The average age (SD) of the cases and controls at the time of recruitment was 63.1 (8.4) and 57.7 (9.4), respectively. The multivariable-adjusted odds ratio of GH for hypertension in middle-aged-to-older women was 4.2 (95% confidence interval, 1.0–17.5) after adjustment for potential confounding factors such as age and body-mass index (BMI) upon recruitment, prepregnancy BMI, and age at first delivery. In conclusion, GH can be an independent risk factor for future hypertension among Japanese women.

Achieving control of resistant hypertension: Not just the number of blood pressure medications

Resistant hypertension (RH) has a prevalence of around 12% and is associated with an increased risk of cardiovascular disease, progression to end-stage renal disease, and even mortality. In 2017, the American College of Cardiology and American Heart Association released updated guidelines that detail steps to ensure proper diagnosis of RH, including the exclusion of pseudoresistance. Lifestyle modifications, such as low salt diet and physical exercise, remain at the forefront of optimizing blood pressure control. Secondary causes of RH also need to be investigated, including screening for obstructive sleep apnea. Notably, the guidelines demonstrate a major change in medication management recommendations to include mineralocorticoid receptor antagonists. In addition to advances in medication optimization, there are several device-based therapies that have been showing efficacy in the treatment of RH. Renal denervation therapy has struggled to show efficacy for blood pressure control, but with a re-designed catheter device, it is once again being tested in clinical trials. Carotid baroreceptor activation therapy (BAT) via an implantable pulse generator has been shown to be effective in lowering blood pressure both acutely and in long-term follow up data, but there is some concern about the safety profile. Both a second-generation pulse generator and an endovascular implant are being tested in new clinical trials with hopes for improved safety profiles while maintaining therapeutic efficacy. Both renal denervation and carotid BAT need continued study before widespread clinical implementation. Central arteriovenous anastomosis has emerged as another possible therapy and is being actively explored. The ongoing pursuit of blood pressure control is a vital part of minimizing adverse patient outcomes. The future landscape appears hopeful for helping patients achieve blood pressure goals not only through the optimization of antihypertensive medications but also through device-based therapies in select individuals.

Body mass index, abdominal adiposity, weight gain and risk of developing hypertension: a systematic review and dose-response meta-analysis of more than 2.3 million participants

OBJECTIVE

This study aimed to test the association between anthropometric measures and risk of developing hypertension.

METHODS

We did a systematic search using PubMed and Scopus, from inception up to January 2017. Prospective cohort studies reporting the risk estimates of hypertension for three or more quantitative categories of indices of general and abdominal adiposity were included. Summary relative risks were calculated using random-effects models.

RESULTS

Fifty-seven prospective cohort studies were included. Summary relative risks were 1.49 (95% confidence interval [CI]: 1.41, 1.58; I²  = 97.4%, n = 50) for a five-unit increment in body mass index, 1.27 (95%CI: 1.15, 1.39; I²  = 95.0%, n = 14) for a 10-cm increment in waist circumference, 1.16 (95%CI: 1.09, 1.23; I²  = 77.8%, n = 5) for weight gain equal to a one-unit increment in BMI, and 1.37 (95%CI: 1.24, 1.51; I²  = 76.4%, n = 8) and 1.74 (95%CI: 1.35, 2.13; I²  = 58.9%, n = 4) for a 0.1-unit increment in waist-to-hip ratio and waist-to-height ratio, respectively. The risk of hypertension increased continuously with increasing all anthropometric measures, and also along with weight gain.

CONCLUSION

Being as lean as possible within the normal body mass index range may be the best suggestion in relation to primary prevention of hypertension.

Prevalence and trends of overweight and obesity in older adults from 10 European countries from 2005 to 2013

Aims: Overweight and obesity are clinical public-health concerns worldwide. Amongst older adults, the prevalence of overweight and obesity is considered high. The purpose of this study was to provide current data regarding the prevalence and trends of overweight and obesity of adults from 2005 to 2013 in 10 European countries. Methods: The data used in the present study were derived from the first, second, fourth and fifth waves of the Survey of Health, Ageing and Retirement in Europe. The present study includes individuals aged ⩾50 years from 10 European countries. Body mass index (BMI) was calculated from self-reported height and weight (kg/m2). Results: The general prevalence of overweight (BMI ⩾25 kg/m2) was slightly above 60% and remained stable between 2005 (60.1%, 95% confidence interval (CI): 59.3–60.9%) and 2013 (60.3%, 95% CI: 59.7–60.9%). On the other hand, the prevalence of obesity (BMI ⩾30 kg/m2) increased significantly (1.6 points, 95% CI: 0.7–2.6) from 17.5% in 2005 to 19.2% in 2013. Although the prevalence of obesity increased in most countries, the only significant increase was observed in Germany (5.8 points, 95% CI: 1.8–9.9). Spain was the only country where the prevalence of obesity decreased significantly (−4.7 points, 95% CI: −8.8 to −0.5). Sex and age differences are reported. Conclusions: Although the prevalence of overweight was stable, the prevalence of obesity rose. Based on the data currently available for Europe, the prevalence of obesity in European older adults has already reached epidemic proportions, which reinforces the need for the development of effective healthy lifestyle programs.

The association between physical activity and chronic diseases in European adults

Chronic diseases are the leading cause of morbidity and mortality and are considered to be at epidemic levels worldwide. This is a cross-sectional multi-country study based on data from the European Social Survey round 7, 2014, comprising 30,826 participants (14,813 men) with mean age 50.4 ± 18.0. Physical activity and chronic diseases were self-reported. Men and women who practiced physical activity more often had lower odds of having heart problems, breathing problems, type 2 diabetes, and obesity. Engaged in physical activity 2-4 times/week and ≥5 times/week decrease the odds of having heart problems, high blood pressure, breathing problems, type 2 diabetes, and obesity, compared with men and women who engaged in physical activity 1 or less times per week. For the women, the practice of physical activity ≥5 times/week was significantly and negatively associated with having cancer, when compared with women who engaged in physical activity 1 or less times per week. Physical activity is associated with a lower risk of chronic diseases, in particular: heart problems, high blood pressure, breathing problems, allergies, type 2 diabetes, and obesity. Furthermore, even small amounts of weekly physical activity seem to decrease the risk of chronic diseases.

Relations of body weight status in early adulthood and weight changes until middle age with hypertension in the Chinese population

We conducted a retrospective cohort study of adult participants from the China Multicenter Collaborative Study of Cardiovascular Epidemiology to explore the relationship between early adulthood weight status, body weight change from age 25 to middle age and hypertension in the Chinese population. Self-reported weight was used to calculate the body mass index (BMI) at age 25. The association between BMI at age 25, subsequent weight change and hypertension was examined using a logistic regression model. Of the 14 635 study participants sampled in 1998, 3525 were diagnosed with hypertension. After adjusting for age, sex and other potential confounding factors, both the BMI at age 25 and weight gain were positively associated with the risk of hypertension (P for trend <0.001). Weight loss could more effectively reduce the risk of hypertension for participants with a higher BMI (BMI⩾24 kg m^-2) at age 25 than for those who experienced a weight change of -2.5-2.5 kg. The odds ratio (OR) and 95% confidence interval (CI) for a weight change of -7.5 to -2.6 kg were 0.63 (0.46-0.86); for a weight change of <-7.5 kg, these statistics were 0.45 (0.32-0.63). For participants who had a lower BMI (18.5-20.9 kg m^-2) at age 25, the OR and 95% CI were 0.86 (0.58-1.26) for a weight change of -7.5 to -2.6 kg and 0.95 (0.44-2.05) for a weight change of <-7.5 kg. Being overweight and obesity in early adulthood and adult weight gain were both independently associated with marked increase in the risk of hypertension in middle-aged men and women. Weight loss may be a protective factor against hypertension for people who were overweight or obese in early adulthood.

What is the evidence base for diagnosing hypertension and for subsequent blood pressure treatment targets in the prevention of cardiovascular disease?

Diagnosing and treating hypertension plays an important role in minimising the risk of cardiovascular disease and stroke. Early and accurate diagnosis of hypertension, as well as regular monitoring, is essential to meet treatment targets. In this article, current recommendations for the screening and diagnosis of hypertension are reviewed. The evidence for treatment targets specified in contemporary guidelines is evaluated and recommendations from the USA, Canada, Europe and the UK are compared. Finally, consideration is given as to how diagnosis and management of hypertension might develop in the future.

Diagnostic and predictive accuracy of blood pressure screening methods with consideration of rescreening intervals: a systematic review for the U.S. Preventive Services Task Force

BACKGROUND

Elevated blood pressure (BP) is the largest contributing risk factor to all-cause and cardiovascular mortality.

PURPOSE

To update a systematic review on the benefits and harms of screening for high BP in adults and to summarize evidence on rescreening intervals and diagnostic and predictive accuracy of different BP methods for cardiovascular events.

DATA SOURCES

Selected databases searched through 24 February 2014.

STUDY SELECTION

Fair- and good-quality trials and diagnostic accuracy and cohort studies conducted in adults and published in English.

DATA EXTRACTION

One investigator abstracted data, and a second checked for accuracy. Study quality was dual-reviewed.

DATA SYNTHESIS

Ambulatory BP monitoring (ABPM) predicted long-term cardiovascular outcomes independently of office BP (hazard ratio range, 1.28 to 1.40, in 11 studies). Across 27 studies, 35% to 95% of persons with an elevated BP at screening remained hypertensive after nonoffice confirmatory testing. Cardiovascular outcomes in persons who were normotensive after confirmatory testing (isolated clinic hypertension) were similar to outcomes in those who were normotensive at screening. In 40 studies, hypertension incidence after rescreening varied considerably at each yearly interval up to 6 years. Intrastudy comparisons showed at least 2-fold higher incidence in older adults, those with high-normal BP, overweight and obese persons, and African Americans.

LIMITATION

Few diagnostic accuracy studies of office BP methods and protocols in untreated adults.

CONCLUSION

Evidence supports ABPM as the reference standard for confirming elevated office BP screening results to avoid misdiagnosis and overtreatment of persons with isolated clinic hypertension. Persons with BP in the high-normal range, older persons, those with an above-normal body mass index, and African Americans are at higher risk for hypertension on rescreening within 6 years than are persons without these risk factors.

PRIMARY FUNDING SOURCE

Agency for Healthcare Research and Quality.

Development of a risk prediction model for incident hypertension in a working-age Japanese male population

The aim of this study was to develop a risk prediction model for incident hypertension in a Japanese male population. Study participants included 15,025 nonhypertensive Japanese male workers (mean age, 38.8±8.9 years) who underwent an annual medical checkup at a company. The participants were followed-up for a median of 4.0 years to determine new-onset hypertension, defined as a systolic blood pressure (BP) ⩾140 mm Hg, a diastolic BP ⩾90 mm Hg, or the initiation of antihypertensive medication. Participants were divided into the following two cohorts for subsequent analyses: the derivation cohort (n=12,020, 80% of the study population) and the validation cohort (n=3005, the remaining 20% of the study population). In the derivation cohort, a multivariate Cox proportional hazards model demonstrated that age, body mass index, systolic and diastolic BP, current smoking status, excessive alcohol intake and parental history of hypertension were independent predictors of incident hypertension. Using these variables, a risk prediction model was constructed to estimate the 4-year risk of incident hypertension. In the validation cohort, the risk prediction model demonstrated high discrimination ability and acceptable calibration, with a C-statistic of 0.861 (95% confidence interval 0.844, 0.877) and a modified Hosmer-Lemeshow χ2 statistic of 15.2 (P=0.085). A risk score sheet was constructed to enable the simple calculation of the approximate 4-year probability of incident hypertension. In conclusion, a practical risk prediction model for incident hypertension was successfully developed in a working-age Japanese male population.

Use of functional aerobic capacity based on stress testing to predict outcomes in normal, overweight, and obese patients

OBJECTIVE

To determine the poorly studied relationship between functional aerobic capacity (FAC) as measured by treadmill stress testing and mortality in normal, overweight, and obese patients.

PATIENTS AND METHODS

Patients were identified retrospectively from the stress testing database at Mayo Clinic in Rochester, Minnesota. We selected 5328 male nonsmokers (mean ± SD age, 51.8±11.5 years) without baseline cardiovascular disease who were referred for treadmill exercise testing between January 1, 1986, and December 31, 1991, and classified them by body mass index (BMI) into normal-weight (18.5-24.9 kg/m(2)), overweight (25.0-29.9 kg/m(2)), and obese (≥30 kg/m(2)) categories. Functional aerobic capacity was assessed by maximal exercise test results based on age- and sex-specific metabolic equivalents, and patients were stratified into fitness quintiles. Cox proportional hazards analysis was used to determine the relationship of all-cause mortality to fitness in each BMI category.

RESULTS

There were 322 deaths during 14 years of follow-up. After adjustment for age and exercise confounders, FAC predicted mortality in the 3 BMI groups. Hazard ratios for FAC less than 80% of predicted vs a reference group with normal BMI and fitness (FAC ≥100%) were 1.754 (95% CI, 0.874-3.522), 1.962 (1.356-2.837), and 1.518 (1.056-2.182) for the normal, overweight, and obese groups, respectively. The CIs of the hazard ratios overlapped with no statistically significant differences (P>.05).

CONCLUSION

A significant increase in mortality occurs with FAC below 80% of predicted for overweight and obese subjects and below 70% for normal weight subjects. Our results suggest that clinicians need not adjust the standard for low fitness in obese patients.

Impact of obesity on incident hypertension independent of weight gain among nonhypertensive Japanese: the Ibaraki Prefectural Health Study (IPHS)

OBJECTIVE

The aim of this study was to examine the association between BMI and risk of incident hypertension among Japanese men and women who are middle-aged and older.

DESIGN

Prospective, population-based cohort study.

PATIENTS

A total of 68 205 nonhypertensive adults (18 336 men and 49 869 women) aged 40-79 years who completed health check-ups in the Ibaraki prefecture, Japan, in 1993 were followed up through 2006. To exclude the impact of BMI change during the follow-up period, a time-dependent covariate Cox proportional hazards model was used to compute the hazard ratios of incident hypertension according to BMI categories. Incident hypertension was defined as a SBP of at least 140 mmHg, a diastolic BP of at least 90 mmHg, and/or hypertensive medication use.

RESULTS

A total of 30 982 adults (45.4%) developed hypertension (9331 men and 21 651 women) during a mean of 3.9 years of follow-up. Compared with a BMI of less than 19.0, time-dependent covariates adjusted hazard ratios [95% confidence interval (CI)] for hypertension among participants with a BMI of at least 25.0 were 1.42 (1.17-1.73) for men aged 40-59 years, 1.34 (1.19-1.51) for men aged 60-79 years, 1.47 (1.33-1.62) for women aged 40-59 years, and 1.29 (1.18-1.41) for women aged 60-79 years.

CONCLUSION

The baseline BMI is associated with future risk for incident hypertension even after accounting for weight change during the follow-up period. Weight loss may be recommended to nonhypertensive obese adults to prevent the development of hypertension.