Tag: hypertension

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


Intensive BP Target of Under 120mmHg Yields even Better Outcomes

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An intensive three-year intervention to lower systolic blood pressure (BP) to less than 120mmHg was more effective at preventing death, heart attack, stroke and other cardiovascular events in adults at high risk for cardiovascular disease, compared to the standard treatment target of under 140mmHg, according to late-breaking science presented at the American Heart Association’s Scientific Sessions 2023.

“Our study provides evidence to support targeting systolic blood pressure to less than 120mmHg in hypertensive patients with high cardiovascular risk and normal or mild-reduced kidney function, regardless of their diabetes status (Type 1, Type 2 or none) or history of stroke,” said lead study author Jing Li, MD, PhD, director of the department of preventive medicine at the National Center for Cardiovascular Diseases in Beijing, China.

The researchers conducted a multi-centre, randomised controlled trial to evaluate the effects of an intensive blood pressure-lowering strategy on the incidence of major cardiovascular events, including heart attack, stroke, cardiovascular death, revascularisation, or hospitalisation or emergency room visit for heart failure, in participants with increased cardiovascular risk.

Participants in the ESPRIT trial were randomised to receive intensive antihypertensive treatment with a systolic BP target of less than 120mmHg (using higher doses and multiple classes of drugs) or standard treatment, with a target measurement of under 140mmHg over a three-year period. Safety was assessed between treatment groups by comparing serious adverse events among participants.

The researchers found that after two years, participants in the intensive treatment group had significantly better outcomes than those receiving standard care. Compared with the standard treatment, the intensive treatment strategy prevented:

  • 12% of heart attacks, stroke, revascularisation procedures, death from cardiovascular causes and hospitalisation or emergency room visit for heart failure;
  • 39% of deaths from cardiovascular causes; and
  • 21% of deaths from any cause.
  • There was no significant difference in serious adverse events of hypotension, electrolyte abnormality, fall resulting in an injury, acute kidney injury or renal failure.

Syncope, or fainting, was one of the serious adverse events used to evaluate safety. Syncope occurred at a rate of 0.4% per year in the intensive group and 0.1% in the standard group. This means that for every 1000 patients receiving the intensive treatment for 3 years, 3 patients would experience a serious adverse event of syncope, while 14 major vascular events and 8 deaths would be further prevented, Li noted.

“These results provide evidence that intensive hypertension treatment focused on achieving systolic blood pressure of less than 120mmHg is beneficial and safe for individuals with high blood pressure and increased cardiovascular risk factors,” Li said. “Implementing this intensive treatment strategy for high-risk adults has the potential to save more lives and reduce the public health burden of heart disease worldwide.”

Study details and background:

  • The ESPRIT trial included 11,255 adults in China. Participants had a baseline systolic blood pressure measurement of 130–180mmHg and either established cardiovascular disease or at least two major risk factors for cardiovascular disease.
  • Participants were an average age of 64.6 years; 41.3% women and 58.7% men.
  • Approximately 27% of the study participants had a history of stroke; approximately 29% had previous coronary heart disease; and approximately 39% had diabetes, Type 1 or Type 2.
  • The trial’s primary outcome was a composite outcome of heart attack, coronary or non-coronary revascularisation, hospitalisation/emergency room visit for heart failure, stroke or CV death. Secondary outcomes included CV outcomes, kidney outcomes and cognitive outcomes.

Study limitations included that the cardiovascular benefits of the intensive intervention emerged after two years, while the intervention only lasted three years, meaning the relatively short study period may underestimate the benefits, Li said. In addition, the study was conducted in China and therefore, the results may not be generalisable to people in other racial and ethnic groups or living in other countries. However, Li also noted that the results were consistent with similar studies in people of other racial and ethnic groups.

Future work will involve examining the longer-term effects of the intensive intervention strategy over the follow-up period.

Source: American Heart Association

Only 30% of Adults Discuss OTC Pain Relievers with Doctors Despite Hypertension Risk

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Only about 30% of US adults have spoken with their health care professional about the adverse effects some over-the-counter (OTC) pain relievers can have on blood pressure. The findings are part of a recent online poll commissioned by the American Heart Association.

Some pain relievers may raise blood pressure, according to the American Heart Association’s most recent Guideline for the Prevention, Detection, Evaluation and Management of High Blood Pressure

“It’s paramount that people who have high blood pressure, or are at risk for it, understand the effects associated with some over-the-counter pain relievers,” said Mitchell S. V. Elkind, MD, MS, FAHA, chief clinical science officer of the American Heart Association and a tenured professor of neurology and epidemiology at Columbia University. “A conversation with a health care professional about pain relief options is essential to preventing and managing high blood pressure.”

High blood pressure affects almost half of all people in the US. According to the American Heart Association’s recent poll, of those who have been diagnosed with high blood pressure, white and Asian adults (40%) are significantly less likely than Black (54.2%) and Hispanic (54.1%) adults to have ever discussed the effect some pain relievers have on blood pressure with a health care professional.
“Some over-the-counter pain relievers are safer than others,” added Elkind. “A conversation with a health care professional regularly about medications you or a loved one takes is an important step in finding safe options and controlling blood pressure.”

The poll conducted by Big Village, a collaborative and consultative research firm, also looked at how often people used OTC pain relievers. Of the close to 3000 US adults aged 18 and older surveyed, nearly 50% took medication for pain once a week or more. Adults aged 45-54 take them most frequently of all age groups polled. Additional findings include:

  • Gen X, people born from 1965 to 1980, are significantly more likely than other generations to take OTC pain relievers multiple times a day, but only 41% of Gen X would initially ask a health care professional for alternative pain relief even if they knew some OTC pain relievers can raise a person’s blood pressure.
  • Gen Z, people born from 1997 to 2012, are significantly less likely (30.5%) than any other generation to initially ask their health care professional for alternative pain relief if they knew some OTC pain relievers can raise a person’s blood pressure.
  • 61% of all respondents had not discussed the effect some over-the-counter pain relievers have on blood pressure with a health care professional.
  • 22% would research an alternative pain reliever online, second only to discussing with a health care professional.

Source: American Heart Association

Researchers ID Two Probiotics that can Help Bring Down Hypertension

Recent studies suggest that probiotics may offer a protective effect against hypertension, but how gut microbiota can regulate blood pressure has remained something of a mystery. Now a study published in mSystems showed that two probiotics, Bifidobacterium lactis and Lactobacillus rhamnosus, returned blood pressure in hypertensive mouse models to normal levels. The researchers also tracked how those probiotics altered the animals’ gut microbial mix over 16 weeks, identifying specific microbes and metabolic pathways that may help explain the protective effect. 

“Accumulated evidence supports an antihypertensive effect of probiotics and probiotic fermented foods in both in vitro and in vivo experiments,” said computational biologist Jun Li, PhD, at the City University of Hong Kong. Her team worked with that of microbiologist Zhihong Sun, PhD, at Inner Mongolia Agricultural University, on the study. “So, we believed that the dietary intake of probiotic foods would well supplement traditional hypertension treatment.” 

Previous studies have connected the rising rates of hypertension worldwide to increasing consumption of sugar. It likely boosts blood pressure through many mechanisms, such as increased insulin resistance or salt retention, but in recent years researchers have also investigated sugar’s effect on the gut microbiome. 

In the new study, the researchers tested the two probiotic strains on mice that developed hypertension after consuming water mixed with fructose. Over the course of 16 weeks, they measured the animals’ blood pressures every 4 weeks. They found that fructose-fed mice that received either probiotic showed significantly lower blood pressures than those fed a high fructose diet and not treated with probiotics. 

In addition, the researchers found no difference between the blood pressure readings of fructose-fed mice that received probiotics and a control group of mice that only drank water. According to Li, that suggests probiotic interventions would maintain blood pressure at normal levels. 

The researchers used shotgun metagenomic sequencing to probe connections between the altered gut microbiota and the change in blood pressure. They found that a high-fructose diet in the mice led to an increase in Bacteroidetes and a decrease in Firmicutes bacteria; however, treatment with probiotics returned those populations to those found in the control group. In addition, the analysis identified new microbial signatures associated with blood pressure: Increased levels of Lawsonia and Pyrolobus bacteria, and reduced levels of Alistipes and Alloprevotella, were associated with lower blood pressure. 

The researchers are now planning a large clinical trial to see if the protective effect of probiotics extend to people with hypertension. “Probiotics present a promising avenue in preventive medicine,” Sun said, “offering potential in regulating hypertension and reshaping our approach to cardiovascular health.”

Source: American Society for Microbiology

In Women, Poor Quality Sleep may Increase Hypertension Risk

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Getting enough sleep is becoming more of a challenge in today’s busy society. New research from investigators in the Channing Division of Network Medicine of Brigham and Women’s Hospital, highlights why getting a good night’s sleep is critical to staying healthy. Their research unveils that women who struggled with getting enough sleep were at greater risk of developing hypertension, or high blood pressure. Results are published in the journal Hypertension.

“These findings suggest that individuals who struggle with symptoms of insomnia may be at risk of hypertension and could benefit from preemptive screening,” explained Shahab Haghayegh, PhD, a research fellow at the Brigham and Harvard Medical School. “Hypertension is associated with many other physical and mental health complications. The sooner we can identify individuals with high blood pressure and treat them for it, the better we can mitigate future health issues.”

Haghayegh and colleagues followed 66 122 participants between 25 and 42 years of age in the Nurses’ Health Study II (NHS2) cohort, all without hypertension at the study’s onset, over sixteen years (from 2001 until 2017). Investigators collected information on participants’ age, race, body mass index (BMI), diet, lifestyle, physical activity, history of sleep apnoea, and family history of hypertension and assessed the incidence of hypertension among the group every two years. They first began measuring sleep duration in 2001, then did so again in 2009, recording the average number of hours slept over a 24-hour period. They also tracked sleeping difficulties, such as having trouble falling or staying asleep or waking up early in the morning, collecting responses at several time points throughout the study.

Data analyses revealed that women with sleeping difficulties had higher BMIs, lower physical activity, and poorer diets, on average. Researcher also found that those who struggled with sleep were more likely to smoke and drink alcohol and have previously gone through menopause.

Among the 25 987 cases of hypertension documented over the follow-up, women who slept less than seven to eight hours a night had a significantly higher risk of developing hypertension, according to the data collected. Similarly, women who had trouble falling asleep and staying asleep were also more likely to develop hypertension. Waking up early in the morning was not associated with this increased risk. Notably, these associations, remained significant after controlling for participant shift work schedules (night versus day shifts) and chronotype (morningness versus eveningness).

While the exact nature of the relationship between sleep and risk of hypertension is unknown, Haghayegh said that sleep difficulties can lead to a chain of events that can increase sodium retention, arterial stiffness, and cardiac output, potentially leading to hypertension. Disruptions to the sleep/wake cycle can also influence blood vessel constriction/relaxation activity and the function of cells that regulate the vascular tone.

One limitation is that the study only looked at the association between sleep and hypertension in women, so researchers hope to expand their work to include men and non-binary participants. A second is that researchers could only collect data on sleep quality at select time points throughout the study. Some of the study’s strengths include the larger number of participants and length of follow-up duration.

Haghayegh emphasises that these findings do not indicate causality. He wants to understand why this association exists and how treating one condition may also treat the other. In future clinical studies, he aims to investigate if sleep medications could have a beneficial effect on blood pressure.

“I hope these findings further underscore the crucial role of quality sleep in our overall well-being. The American Academy of Sleep Medicine recommends sleeping seven or more hours a night, and if you cannot fall or stay asleep, it might be worth exploring why that is,” said Haghayegh. “This study highlights yet another reason why getting a good night’s sleep is so important.”

Source: Brigham and Women’s Hospital