Tag: hypertension

Adequate Sleep Significantly Reduces Hypertension Risk in Teens

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Adolescents who meet the recommended guidelines of nine to 11 hours of sleep per day were shown to have a significantly lower risk of hypertension, according to a new study from UTHealth Houston.  

Recently published in the Journal of the American Heart Associationthe research revealed that adolescents had a 37% lower risk of developing incidents of high blood pressure by meeting healthy sleep patterns, and underscoring the importance of adequate sleep behaviour. The research further explored the impact of environmental factors potentially impacting sleep.  

“Disrupted sleep can lead to changes in the body’s stress response, including elevated levels of stress hormones like cortisol, which in turn can increase blood pressure,” said first author Augusto César Ferreira De Moraes, PhD, assistant professor in the Department of Epidemiology at UTHealth Houston School of Public Health. 

De Moraes and his team analysed data from 3320 adolescents across the US to investigate incidents of high blood pressure during nighttime sleep cycles. Scientists identified a rise in hypertension incidents over two data periods, 2018-2020 and 2020-2022, showing an increase from 1.7% to 2.9%. The data included blood pressure readings and Fitbit assessments, which measured total sleep time and REM sleep duration at night. The study’s design analysed covariates such as Fitbit-tracked sleep, blood pressure, and neighbourhood noise by residential geocodes, allowing for a thorough examination of environmental noise exposure for each participant. 

Neighbourhood/community noise was not significantly associated with the incidence of hypertension. Environmental factors, such as neighbourhood noise, point to the need for longer-term studies to investigate the relationship between sleep health and hypertension, particularly in relation to socioeconomic status, stress levels, and genetic predispositions. 

The study emphasises the importance of improved sleep behaviours and meeting recommendations. “Consistent sleep schedules, minimising screen time before bed, and creating a calm, quiet sleep environment can all contribute to better sleep quality,” advises Martin Ma, MPH, second author of the study and recent graduate of the school. “Although environmental noise didn’t directly affect hypertension in this study, maintaining a quiet and restful sleep environment is still important for overall well-being.” 

Source: University of Texas Health Science Center at Houston

An Extra Five Minutes of Exercise a Day could Reduce Blood Pressure

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New research suggests that adding a small amount of daily physical activity, such as uphill walking or stair-climbing, may help to lower blood pressure. The findings were published in Circulation

Just five minutes of activity a day was estimated to potentially reduce blood pressure, while replacing sedentary behaviours with 20–27 minutes of exercise per day, including uphill walking, stair-climbing, running and cycling, was also estimated to lead to a clinically meaningful reduction in blood pressure. The study was done by experts from the ProPASS (Prospective Physical Activity, Sitting and Sleep) Consortium, an international academic collaboration led by the University of Sydney and University College London (UCL)

Joint senior author Professor Emmanuel Stamatakis, Director of the ProPASS Consortium said: “High blood pressure is one of the biggest health issues globally, but unlike some major causes of cardiovascular mortality there may be relatively accessible ways to tackle the problem in addition to medication.”

“The finding that doing as little as five extra minutes of exercise per day could be associated with measurably lower blood pressure readings emphasises how powerful short bouts of higher intensity movement could be for blood pressure management.”

The research team analysed health data from 14 761 volunteers in five countries to see how replacing one type of movement behaviour with another across the day is associated with blood pressure.

Each participant used a wearable accelerometer device on their thigh to measure their activity and blood pressure throughout the day and night. 

Daily activity was split into six categories: sleep, sedentary behaviour (such as sitting), slow walking, fast walking, standing, and more vigorous exercise such as running, cycling or stair climbing.

The team modelled statistically what would happen if an individual changed various amounts of one behaviour for another in order to estimate the effect on blood pressure for each scenario and found that replacing sedentary behaviour with 20-27 minutes of exercise per day could potentially reduce cardiovascular disease by up to 28 percent at a population level.

First author Dr Jo Blodgett from UCL said: “Our findings suggest that, for most people, exercise is key to reducing blood pressure, rather than less strenuous forms of movement such as walking.

“The good news is that whatever your physical ability, it doesn’t take long to have a positive effect on blood pressure. What’s unique about our exercise variable is that it includes all exercise-like activities, from running for a bus or a short cycling errand, many of which can be integrated into daily routines.

“For those who don’t do a lot of exercise, walking did still have some positive benefits for blood pressure. But if you want to change your blood pressure, putting more demand on the cardiovascular system through exercise will have the greatest effect.”

Professor Mark Hamer, joint senior author of the study and ProPASS Deputy Director from UCL, said: “Our findings show how powerful research platforms like the ProPASS consortium are for identifying relatively subtle patterns of exercise, sleep, and sedentary behaviour, that have  significant clinical and public health importance.”

Source: University of Sydney

Commonly Used Arm Positions can Greatly Overestimate BP Readings

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A study led by Johns Hopkins Medicine researchers concludes that commonly used ways of positioning the patient’s arm during blood pressure (BP) screenings can substantially overestimate test results and may lead to a misdiagnosis of hypertension.

In a report on the study, published in JAMA Internal Medicine, investigators examined the effects of three different arm positions: an arm supported on a desk, arm supported on a lap, and an unsupported arm hanging at the patient’s side. Researchers found that lap support overestimated systolic pressure by nearly 4mmHg, and an unsupported arm hanging at the side overestimated systolic pressure by nearly 7mmHg.

The findings confirm that arm position makes a “huge difference” when it comes to an accurate blood pressure measurement, says Tammy Brady, MD, PhD, senior author of the study. And they underscore the importance of adhering to clinical guidelines calling for firm support on a desk or other surface when measuring blood pressure, the investigators add.

The latest clinical practice guidelines from the American Heart Association emphasise several key steps for an accurate measurement – including appropriate cuff size, back support, feet flat on the floor with legs uncrossed, and an appropriate arm position, in which the middle of an adjustable BP cuff is positioned at mid-heart level on an arm supported on a desk or table.

Despite these recommendations, the researchers say BP is too often measured with patients seated on an exam table without any, or inadequate, arm support. In some cases, a clinician holds the arm, or the patient holds an arm in their lap. In the new Johns Hopkins study, the researchers recruited 133 adult participants (78% Black, 52% female) between Aug. 9, 2022, and June 1, 2023. Study participants, who ranged from age 18 to 80, were sorted at random into one of six possible groups that differed by order of the three seated arm positions. Measurements were taken during a single visit between 9 a.m. and 6 p.m. Before BP measures were taken, all participants first emptied their bladders and then walked for two minutes to mimic a typical clinical scenario in which people walk into a clinic or office before screening takes place. They then underwent a five-minute, seated rest period with their backs and feet supported. Each person, wearing an upper arm BP cuff selected and sized based on their upper arm size, had three sets of triplicate measurements taken with a digital blood pressure device 30 seconds apart.

Upon completion of each set of three measurements, the cuff was removed, participants walked for two minutes and rested for five minutes. In the same visit, they then underwent a fourth set of triplicate measurements with their arm supported on a desk, a set used to account for well-known variations in BP readings. All of the measurements were conducted in a quiet and private space, and participants were asked not to talk to researchers or use their phones during the screening.

Researchers found that BP measurements obtained with arm positions frequently used in clinical practice – an arm on the lap or unsupported at the side – were markedly higher than those obtained when the arm was supported on a desk, the standard, recommended arm position. Supporting the arm on the lap overestimated systolic and diastolic BP by 3.9mmHg and 4.0mmHg, respectively. An unsupported arm at the side overestimated systolic by 6.5mmHg and diastolic by 4.4mmHg.

“If you are consistently measuring blood pressure with an unsupported arm, and that gives you an overestimated BP of 6.5mmHg, that’s a potential difference between a systolic BP of 123 and 130, or 133 and 140 – which is considered stage 2 hypertension,” says study author Sherry Liu, MHS, an epidemiology research coordinator at Johns Hopkins Bloomberg School of Public Health.

Investigators caution that their study results may only apply during screenings with automated BP devices, and may not apply to readings done with other BP devices.

However, Brady says, the findings suggest that clinicians need to pay better attention to best practice guidelines, and that patients “must advocate for themselves in the clinical setting and when measuring their BP at home.”

Source: Johns Hopkins Medicine

Exposure to Chronic Occupational Noise Drives up Blood Pressure

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Noise exposure is a known occupational hazard in some jobs, particularly for hearing loss, physical and psychological stress, and reduced concentration. A new study presented at the ACC Asia 2024 conference found in adult power loom weavers, chronic noise exposure not only increased their blood pressure overall, but also each year of exposure increased their odds of having high blood pressure by 10%.

“While the mechanism is still not well-explored, it is thought that the stress response by the body to chronic sound exposure causes hormonal imbalances that gradually leads to a permanent elevation of blood pressure,” said Golam Dastageer Prince, MBBS, MPH, medical officer at DGHS Bangladesh and the study’s lead author. “High blood pressure impacts more than a billion people worldwide and just 1 in 5 have it under control, yet it is a major cause of premature death. In addition to treating the high blood pressure through appropriate means, we must find ways to mitigate the exposure to the noise if we want to reduce the cardiovascular risk of these patients.”

Researchers at the Directorate of General Health Services in Bangladesh looked at 289 adult workers in selected weaving factories in the Araihazar sub-district of Narayanganj, Bangladesh, from January to December 2023. Participants took a face-to-face interview to complete a questionnaire covering sociodemographic variables, behaviour, dietary habits and family medical history. Blood pressure, height, weight and noise intensity were measured following standard procedures by the researchers.

The study cohort was predominantly male and married and were about 34 years of age on average. According to the researchers, a notable proportion of the cohort was illiterate. Workplace exposure duration averaged nearly 16 years, with noise intensity ranging from 96–111 decibels. In the United States the National Institute for Occupational Safety and Health has established the recommended exposure limits for occupational noise exposures to be 85 decibels on average over an eight-hour workday. Sounds at or below 70 decibels are generally considered safe.

According to Prince, none of the study population was found to be wearing ear protection personal protective equipment.

“Hopefully we can raise awareness of not only noise-induced hearing loss, but the impact of noise on blood pressure and workers’ behaviors and attitudes towards using personal protective equipment,” Prince said. “Pushing for structural improvements to industries may also help us improve the health safety of these workers.”

The study population had a 31.5% rate of high blood pressure with an additional 53.3% being prehypertensive. The study also found a positive correlation between blood pressure and noise exposure duration. Each year of exposure was found to increase high blood pressure odds by 10%, even after adjusting for age, body mass index and smoking status.

“As the study focused on workers exposed to more than 85 decibels noise for long periods of time, any profession causing workers to experience similar exposure might experience similar blood pressure impacts,” Prince said. “We definitely need more exploratory studies to reveal more information about the potential mechanisms and long-term health outcomes.”

Recent studies have shown that living near noise pollution, including highways, trains and air traffic, can have an impact on cardiovascular health. However, the current study may not apply to noise experienced during daily life. Noise pollution experienced near home typically ebbs and flows, while the industrial exposures in the study are typically continuous in pattern due to the machinery and remain at a constant sound level, according to Prince.

Source: American College of Cardiology

Infertility Treatment Associated with Double the Risk of Postpartum Cardiovascular Disease

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A study by Rutgers Health experts of more than 31 million hospital records shows that infertility treatment patients were twice as likely as those who conceived naturally to be hospitalised with heart disease in the year after delivery. The results were published in the Journal of Internal Medicine.

Compared to those who conceived naturally, patients who underwent infertility treatment 2.16 times as likely be hospitalised for hypertension.

“Postpartum checkups are necessary for all patients, but this study indicates they are particularly important for patients who undergo infertility treatment to achieve a conception,” said Rei Yamada, an obstetrics and gynaecology resident at Rutgers Robert Wood Johnson Medical School and lead author of the study.

The study authors say their results support standards of care that now call for an initial postpartum checkup three weeks after delivery, standards that some health systems have yet to adopt. Much of the elevated risk came in the first month after delivery, particularly for patients who developed dangerously high blood pressure.

“And these results aren’t the only ones to indicate that follow-up should occur early,” said Cande Ananth, chief of the Division of Epidemiology and Biostatistics in the Department of Obstetrics, Gynecology, and Reproductive Sciences at Rutgers Robert Wood Johnson Medical School and senior author of the study. “We have been involved in a series of studies over the past few years that have found serious risks of heart disease and stroke to various high-risk patient populations within those initial 30 days after delivery – risks that could be mitigated with earlier follow-up care.”

The study analysed the Nationwide Readmissions Database, which contains nationally representative data on about 31 million hospital discharges and readmissions per year. The database contains diagnosis codes, which let researchers find specific populations and identify reasons for readmission.

The researchers used data from more than 31 million patients who were discharged following delivery from 2010 to 2018, including 287 813 patients who had undergone any infertility treatment.

Although infertility treatment predicted a sharply elevated risk of heart disease, the study authors said the relative youth of infertility treatment patients kept their overall risk fairly low. Just 550 of every 100 000 women who received infertility treatment and 355 of every 100 000 who conceived naturally were hospitalized with cardiovascular disease in the year after delivery.

The cause of the elevated risk of heart disease associated with infertility treatment remains unclear. The increase in heart disease could stem from the infertility treatments themselves, the underlying medical issues that made patients infertile or some other cause.

“Looking forward, I’d like to see if different types of infertility treatment and, importantly, medications are associated with different risk levels,” said Yamada. “Our data gave no information about which patients had undergone which treatment. More detailed information might also provide insight into how infertility treatment impacts cardiovascular outcomes.”

Source: Rutgers University

Study Finds New Genetic Markers for Blood Pressure

NIH-led study finds genetic markers that explain up to 12% of the differences between two people’s blood pressure.

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National Institutes of Health researchers and collaborators have discovered over 100 new regions of the human genome, also known as genomic loci, that appear to influence a person’s blood pressure. Results of the study also point to several specific genomic loci that may be relevant to iron metabolism and a type of cellular receptor known as adrenergic receptors. 

The study, published in Nature Geneticsis one of the largest such genomic studies of blood pressure to date, including data from over 1 million participants and laying the groundwork for researchers to better understand how blood pressure is regulated. Such insights could point to potential new drug targets. 

“Our study helps explain a much larger proportion of the differences between two people’s blood pressure than was previously known,” said first author Jacob Keaton, PhD. “Our study found additional genomic locations that together explain a much larger part of the genetic differences in people’s blood pressure. Knowing a person’s risk for developing hypertension could lead to tailored treatments, which are more likely to be effective.” 

Hypertension often runs in families, meaning that there is a genetic component to developing the condition in addition to environmental contributions such as a high-salt diet, lack of exercise, smoking and stress.

To understand the genetics of blood pressure, the researchers combined four large datasets from genome-wide association studies of blood pressure and hypertension. After analysing the data, they found over 2000 genomic loci linked to blood pressure, including 113 new regions. Among the newly discovered genomic loci, several reside in genes that play a role in iron metabolism, confirming previous reports that high levels of accumulated iron can contribute to cardiovascular disease.  

The researchers also confirmed the association between variants in the ADRA1A gene and blood pressure. ADRA1A encodes a type of cell receptor, called an adrenergic receptor, that is currently a target for blood pressure medication, suggesting that other genomic variants discovered in the study may also have the potential to be drug targets to alter blood pressure. 

“This study shows that these big genome-wide association studies have clinical relevance for finding new drug targets and are needed to discover more drug targets as we go forward,” said Dr Keaton. 

From these analyses, the researchers were able to calculate a polygenic risk score, which combines the effects of all genomic variants together to predict blood pressure and risk for hypertension. These risk scores consider which genomic variants confer risk for hypertension and reveal clinically meaningful differences between people’s blood pressure. 

Polygenic risk scores have potential to serve as a useful tool in precision medicine, but more diverse genomic data is needed for them to be applicable broadly in routine health care. While the collected data was mostly from people of European ancestry, the polygenic risk scores were also applicable to people of African ancestry.

Source: National Institutes of Health

Getting too Little Sleep Linked to High Blood Pressure

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Sleeping fewer than seven hours is associated with a higher risk of developing hypertension over time, according to a study presented at the American College of Cardiology’s Annual Scientific Session.

While the association between sleep patterns and hypertension has been reported, evidence about the nature of this relationship has been inconsistent, according to researchers. The current analysis pools data from 16 studies conducted between January 2000 and May 2023, evaluating hypertension incidence in 1 044 035 people from six countries without a prior history of hypertension over a median follow-up of five years (follow-up ranged from 2.4 to 18 years). Short sleep duration was significantly associated with a higher risk of developing hypertension after adjusting for demographic and cardiovascular risk factors, including age, sex, education, BMI, blood pressure, smoking status etc. Furthermore, the association was found to be even stronger for those getting less than five hours of sleep.

“Based on the most updated data, the less you sleep – that is less than seven hours a day – the more likely you will develop high blood pressure in the future,” said Kaveh Hosseini, MD, assistant professor of cardiology at the Tehran Heart Center in Iran and principal investigator of the study. “We saw a trend between longer sleep durations and a greater occurrence of high blood pressure, but it was not statistically significant. Getting seven to eight hours of sleep, as is recommended by sleep experts, may be the best for your heart too.”

The study found that sleeping less than seven hours was associated with a 7% increased risk of developing hypertension, which spiked to 11% when reported sleep duration was less than five hours. By comparison, diabetes and smoking are known to heighten one’s risk of hypertension by at least 20%, Hosseini said.

While the study did not look at why this might be the case, Hosseini said that disrupted sleep could be to blame. For example, he said lifestyle habits or comorbid conditions such as overeating, alcohol use, nightshift work, certain medication use, anxiety, depression, sleep apnoea or other sleep disorders may be factors.

Researchers were surprised there were no age-based differences in the association between sleep duration and hypertension given that sleep patterns tend to shift with age. Participants ranged in age from 35.4 years to 60.9 years and 61% were female. When compared with men, females who reported less than seven hours of sleep had a 7% greater risk of developing hypertension.

“Getting too little sleep appears to be riskier in females,” Hosseini said. “The difference is statistically significant, though we are not sure it’s clinically significant and should be further studied. What we do see is that lack of good sleep patterns may increase the risk of high blood pressure, which we know can set the stage for heart disease and stroke.”

It’s important for people to talk with their health care team about their sleep patterns, especially if they have disrupted sleep that might be due to obstructive sleep apnoea. Sleep apnoea has been tied to higher rates of high blood pressure, stroke and coronary artery disease.

This study has several limitations, including that sleep duration was based on self-reported questionnaires, so changes in sleep duration over the follow-up period were not assessed. Moreover, there were variations in how short sleep duration was defined between the studies (fewer than five or six hours).

“Further research is required to evaluate the association between sleep duration and high blood pressure using more accurate methods like polysomnography, a method for evaluating sleep quality more precisely,” Hosseini said. “Moreover, the variations in reference sleep duration underline the need for standardised definition in sleep research to enhance the comparability and generalisability of findings across diverse studies.”

Source: American College of Cardiology

Raised Blood Pressure is the Leading Risk Factor for Death in Australia

Hypertension has contributed at least 44% to CVD deaths over thirty years, more than dietary factors and tobacco

Raised blood pressure has been the leading risk factor for death in Australia for the past three decades, according to a study published February 21, 2024, in the open-access journal PLOS ONE led by Alta Schutte and Xiaoyue Xu from The George Institute for Global Health and UNSW, Sydney, with colleagues across Australia. It is also the main contributor to deaths from cardiovascular disease (CVD) specifically.

Raised blood pressure has long been recognized as a contributing factor to CVD and death, but is not always prioritized in national health plans. In this study, researchers focused on Australia, which lags behind other high-income countries in hypertension control. Data on how raised blood pressure compares to other risk factors for CVD burden – and how this changes over time – can help to guide public health agendas and inform the effectiveness of public health policies.

Researchers analysed epidemiologic data from the Global Burden of Disease (GBD) study between 1990 and 2019 to determine the leading risk factors associated with both all-cause and CVD deaths, over time and between gender and age groups. The GBD study provides data on nearly 400 diseases and 87 risk factors across 204 countries.

They found that while the contribution of raised blood pressure to these outcomes declined early in the study period (from around 54% to around 44%), it persisted as the leading risk factor for all-cause and CVD deaths. Dietary factors and tobacco use rounded out the top three risk factors. These findings strongly align with the recently established National Hypertension Taskforce of Australia, which aims to improve Australia’s blood pressure control rates from 32% to 70% by 2030 (Hypertension – Australian Cardiovascular Alliance [ozheart.org]). The research findings further advocate for the prioritisation of blood pressure control on the public health agenda.

Differences by gender and age were also seen. For example, the contribution of raised blood pressure to stroke-related deaths in males aged 25–49 years were higher than other age groups, exceeding 60% and increasing steeply over time.

The study reinforces the importance of blood pressure control and awareness. The researchers hope that the data will urge policymakers to prioritise blood pressure control efforts in Australia and will provide insight into age groups and populations that would benefit from more targeted action.

The authors add: “There is no doubt that raised blood pressure has remained the leading risk factor for all-cause and cardiovascular deaths in Australia across the past three decades. Our findings support actions to strengthen primary care and to improve the prevention, detection, treatment and control of raised blood pressure, with the goal of significantly reducing all-cause and cardiovascular deaths in Australia over the next decade.”

Long-term Blood Pressure Control from Bariatric Surgery is Most Effective

Sleeve gastrectomy. Credit: Scientific Animations CC4.0

Compared to antihypertensives alone, bariatric surgery is more effective in controlling hypertension rates in people with obesity and uncontrolled hypertension, according to a study published in the Journal of the American College of Cardiology. People who underwent bariatric surgery had lower BMI and were on fewer medications after five years while maintaining normal blood pressure levels than those who only used antihypertensive medications.

“In clinical practice, obesity is an overlooked condition. As a consequence, there is a frequent failure in approaching obesity as a crucial step for mitigating the risk of important cardiovascular risk factors including hypertension,” said Carlos Aurelio Schiavon, MD, FACS, lead author of the study and a surgeon specialising in bariatric surgery at Heart Hospital (hcor) and BP Hospital in Sao Paulo.

Researchers in this study looked at the impact of treating obesity to lower hypertension. While new weight loss drugs exist, long-term adherence to medication can be challenging.

This study looks at bariatric surgery as a better long-term solution to control obesity and, as a result, hypertension.

The GATEWAY trial included 100 people (76% of whom were female) who had a body mass index (BMI) of around 36.9kg/m2. All participants had hypertension and were using at least two medications. People with previous cardiovascular events and poorly controlled Type 2 diabetes were excluded.

Subjects were assigned to either Roux-en-Y gastric bypass with medical therapy or medial therapy alone and the primary outcome was reduction of at least 30% antihypertensive medications while maintaining blood pressure levels less than 140/90mmHg at five years.

At five years, BMI was 28.01kg/mfor those who received bariatric surgery and 36.40kg/mfor those on medical therapy alone.

People who had bariatric surgery had an 80.7% reduction in the number of medications they were taking compared to a 13.7% reduction in those only using medical therapy.

Hypertension remission, defined as controlled blood pressure without medications, was 46.9% in those who underwent bariatric surgery compared to 2.4% in those on medical therapy alone.

“Our results underscore the importance of approaching obesity in reducing hypertension rates,” Schiavon said.

Limitations of the study include that it was a single-center, open-label study with a small sample size and there was loss of follow up in some patients.

In an accompanying editorial comment, Michael Hall, MD, MSc, professor and chair of the Department of Medicine at the University of Mississippi Medical Center, said the study provides important long-term data on the benefits of gastric bypass on weight loss and blood pressure control, but questions remain.

“Further studies assessing the threshold for bariatric surgery in people with obesity, optimal timing of bariatric surgery in obese people with cardiometabolic diseases, type of bariatric surgery and comparative studies of obesity pharmacotherapies and bariatric surgery are needed to clarify the optimal treatment pathways for this common and growing disease,” he said.

Source: American College of Cardiology

Reduced Blood Lead Levels Tied to Lower Blood Pressure

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Researchers found that small declines in blood lead levels were associated with long-term cardiovascular health improvements in American Indian adults. Participants who had the greatest reductions in blood lead levels saw their systolic blood pressure fall by about 7mmHg, comparable to the effects of antihypertensives.

The findings as reported from researchers at Columbia University Mailman School of Public Health and NIEHS and NHLBI are published in the Journal of the American Heart Association.

“This is a huge win for public health,” said senior author Anne E. Nigra, PhD, assistant professor of environmental health sciences at Columbia Mailman School of Public Health.

“We saw that even small decreases in a person’s blood lead levels can have meaningful health outcomes.”

Nigra and her co- authors, including Wil Lieberman-Cribbin, MPH, also at Columbia Mailman School, credit these improvements in large part to public health and policy changes that have occurred over the last few decades.

In addition to seeing improvements in systolic blood pressure, the investigators found that reductions in blood lead levels were associated with reductions in a marker associated with hypertrophic cardiomyopathy and heart failure.

To conduct this research, investigators partnered with 285 American Indian adults through an extension of the Strong Heart Study, the largest study following cardiovascular health outcomes and risk factors among American Indian adults.

The researchers looked at blood lead levels and blood pressure readings over time in participants living in one of four tribal communities. Lead was first measured in blood collected during the 1997–1999 study visit and again in blood collected during a follow-up visit between 2006–2009.

During this time, participants’ blood pressure was taken and they participated in medical exams, including echocardiographs to assess their heart’s structure and function. Multiple factors were controlled for, including social variables, cardiovascular disease risks, and medical history.

At the start of the study, the average blood lead level was 2.04µg/dL. Throughout the study, the average blood lead level fell by 0.67µg/dL, or 33%.

The most significant changes, categorized by participants with average starting blood lead levels of 3.21 µg/dL and who experienced reductions of about 1.78 µg/dL, or 55%, were linked to a 7mmHg reduction in systolic blood pressure.

“This is a sign that whatever is happening in these communities to reduce blood lead levels is working,” said Mona Puggal, MPH, an epidemiologist in the Division of Cardiovascular Sciences at the National Heart, Lung, and Blood Institute (NHLBI). “The reductions in blood pressure are also comparable to improvements you would see with lifestyle changes, such as getting 30 minutes of daily exercise, reducing salt intake, or losing weight.”

The reductions in blood lead levels observed in the study are similar to those seen in the general US population following policies and efforts implemented within the past 50 years to reduce lead exposure through paint, gasoline, water, plumbing, and canned items.

Source: Columbia University’s Mailman School of Public Health

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