Cardiovascular disease

Posted on Cardiovascular disease, Diabetes

World’s most common heart valve disease linked to insulin resistance in large study

Newly-established link could open doors for new treatments of aortic stenosis – which effects 2% of over 65s worldwide
Newly-established links could open doors for new treatments for aortic stenosis, affecting 2% of over 65s worldwide.

A sizeable new population study of men over 45 indicates insulin resistance may be an essential risk factor for the development of the world’s most common heart valve disease – aortic stenosis (AS). 

Published today in the peer-reviewed journal Annals of Medicine, the findings are believed to be the first to highlight this previously unrecognised risk factor for the disease. 

It is hoped that by demonstrating this link between AS and insulin resistance – when cells fail to respond effectively to insulin and the body makes more than necessary to maintain normal glucose levels – new avenues for preventing the disease could open.  

Aortic stenosis is a debilitating heart condition. It causes the aortic valve to narrow, restricting blood flow out of the heart. Over time, the valve thickens and stiffens, making the heart work harder to pump blood effectively around the body. If not addressed, this can gradually cause damage that can lead to life-threatening complications, such as heart failure. 

People living with AS can take years to develop symptoms, which include chest pain, tiredness, shortness of breath and heart palpitations. Some may never experience symptoms but may still be at risk of heart failure and death. Previously identified risk factors for AS include age, male sex, high blood pressure, smoking and diabetes. 

Insulin resistance, which often develops years before the onset of type 2 diabetes, occurs when cells fail to respond effectively to insulin, the hormone responsible for regulating blood glucose levels. In response, the body makes more insulin to maintain normal glucose levels – leading to elevated blood insulin levels (hyperinsulinemia).  

In the current study, researchers analysed data from 10,144 Finnish men aged 45 to 73, all initially free of AS, participating in the Metabolic Syndrome in Men (METSIM) Study. At the start of the study, the researchers measured several biomarkers, including those related to hyperinsulinemia and insulin resistance. After an average follow-up period of 10.8 years, 116 men (1.1%) were diagnosed with AS. 

The team identified several biomarkers related to insulin resistance – fasting insulin, insulin at 30 minutes and 120 minutes, proinsulin, and serum C-peptide – associated with increased AS risk. These biomarkers remained significant predictors of AS, even after adjusting for other known risk factors, such as body mass index (BMI) and high blood pressure, or excluding participants with diabetes or an aortic valve malformation. 

The researchers then used advanced statistical techniques to isolate key biomarker profiles, identifying two distinct patterns that indicate insulin resistance as a predictor of AS, independent of other cardiovascular risk factors, such as age, blood pressure, diabetes, and obesity. 

“This novel finding highlights that insulin resistance may be a significant and modifiable risk factor for AS,” says lead author Dr Johanna Kuusisto, from the Kuopio University Hospital in Finland. 

“As insulin resistance is common in Western populations, managing metabolic health could be a new approach to reduce the risk of AS and improve cardiovascular health in ageing populations. Future studies are warranted to determine whether improving insulin sensitivity through weight control and exercise measures can help prevent the condition.” 

This study’s major strengths include its large population-based cohort and long follow-up period. However, its limitations include the sole focus on male subjects and the relatively small number of AS cases, which may limit the generalisability of the findings to other populations. 

Posted on A to Z of Medical Conditions, Cardiovascular disease, Exercise

Live well, think well: Research shows healthy habits tied to brain health

Type 2 diabetes and prediabetes are associated with accelerated brain ageing, according to a new study from Karolinska Institutet in Sweden published in the journal Diabetes Care. The good news is that this may be counteracted by a healthy lifestyle.

In middle-aged people, having risk factors like blood pressure, blood sugar and cholesterol that are not well-controlled, combined with not following certain healthy habits, including exercise, diet and sleep, are linked to a higher risk of stroke, dementia or depression later in life,. 

The eight cardiovascular and brain health factors, known as the American Heart Association’s Life’s Essential 8, are being active, eating better, maintaining a healthy weight, not smoking, maintaining healthy blood pressure, getting enough sleep, and controlling cholesterol and blood sugar levels.

“Brain health is paramount for the optimal well-being of every person, enabling us to function at our highest level and constantly adapt in the world,” said study author Santiago Clocchiatti-Tuozzo, MD, MHS, of Yale University in New Haven, Connecticut, and member of the American Academy of Neurology. “Our study found that making these healthy lifestyle choices in middle age can have meaningful impacts on brain health later in life.”

For the study, researchers evaluated data from 316,127 people, with an average age of 56, who were followed over five years.

Researchers analyzed participants’ scores across the eight essential cardiovascular health factors and organized them into three categories: optimal, intermediate, and poor.

Of the total group, 64,474 had optimal scores, 190,919 had intermediate scores, and 60,734 had poor scores.

Researchers then evaluated health records to identify who developed any of the following neurological conditions: stroke, dementia or late-life depression. Poor brain health was defined as developing these conditions during the follow-up years.

1.2% of participants met the definition for poor brain health, with 3,753 conditions. Of those with optimal Life’s Essential Eight scores, 0.7% met the definition of poor brain health, compared to 1.2% with intermediate scores and 1.8% with poor scores.

After adjusting for factors that could affect the risk of these three neurological conditions, such as age, sex, race and ethnicity, researchers found that people with poor scores on the healthy lifestyle factors were more than twice as likely to develop any of the three neurological conditions compared to those people with optimal scores. Researchers also found that people with an intermediate score had a 37% higher risk of having one of the three neurological conditions than those with an optimal score.

“Because the risk factors we looked at are all ones that people can work to improve, our findings highlight the potential benefits of using these eight cardiovascular and brain health factors to guide healthy lifestyle choices,” Clocchiatti-Tuozzo said. “More research is needed to understand this link between lifestyle habits and brain health, as well as how social factors like race and ethnicity can influence this connection.”

Posted on Cardiovascular disease, Diabetes, Diet, Obesity

Going vegan will save more than $650 a year in grocery costs.

According to new research, a low-fat vegan diet cuts food costs by 19%, or $1.80 per day, compared with a standard American diet that includes meat, dairy, and other animal products. The study also found that a Mediterranean diet costs 60 cents more per day. Total food costs on a vegan diet were 25% lower, $2.40 per day, compared with the Mediterranean diet.

“As grocery prices remain quite high, consumers might consider replacing meat and dairy products with a low-fat vegan diet of fruits, vegetables, grains, and beans. This change could potentially save more than $650 a year on grocery expenses compared to a standard American diet and over $870 compared to the Mediterranean diet,” says Hana Kahleova, MD, PhD, the lead author of the study and director of clinical research at the Physicians Committee for Responsible Medicine. “Adopting a vegan diet can not only lead to financial savings but also improve health by reducing the risk or severity of conditions such as obesity, type 2 diabetes, and heart disease.”

The decrease in costs on the vegan diet was mainly attributable to savings of $2.90 per day on meat, 50 cents per day on dairy products, and 50 cents per day on added fats. These savings outweighed the increased spending of 50 cents per day on vegetables, 30 cents per day on grains, and 50 cents on meat alternatives on the vegan diet.

The new research is a secondary analysis of a previous study by the Physicians Committee, which compared a low-fat vegan diet to a Mediterranean diet. In this study, participants were randomly assigned to follow either a low-fat vegan diet—which included fruits, vegetables, grains, and beans—or a Mediterranean diet, which emphasized fruits, vegetables, legumes, fish, low-fat dairy, and extra-virgin olive oil, for 16 weeks. There were no calorie restrictions for either group. After this phase, participants returned to their baseline diets for a four-week washout before switching to another diet for 16 weeks. The findings showed that the low-fat vegan diet resulted in better outcomes for weight, body composition, insulin sensitivity, and cholesterol levels compared to the Mediterranean diet.

For the food cost assessment, intakes from the study participants’ dietary records were linked to the U.S. Department of Agriculture Thrifty Food Plan, 2021, a database of national food prices, which are calculated from data collected for the consumer price index. The reduction in costs associated with a vegan diet primarily resulted from savings of $2.90 per day on meat, $0.50 per day on dairy products, and $0.50 per day on added fats. These savings exceeded the additional expenses of $0.50 per day on vegetables, $0.30 per day on grains, and $0.50 per day on meat alternatives. Overall, the vegan diet proved to be more economical.

Posted on Cardiovascular disease, Exercise

Sitting down too long can harm heart health, even for active people

Approximately 10 hours or more of sedentary behavior per day is associated with heightened risk of heart failure and cardiovascular death, even in those who regularly exercise
Spending ten or more hours per day in sedentary behaviour is linked to an increased risk of heart failure and cardiovascular death, even in individuals who exercise regularly.

A study published in JACC, the flagship journal of the American College of Cardiology, and presented at the American Heart Association’s Scientific Sessions 2024, indicates that spending more time sitting, reclining, or lying down during the day may increase the risk of cardiovascular disease (CVD) and death. Specifically, the study found that engaging in more than roughly 10 and a half hours of sedentary behaviour per day is significantly associated with an increased risk of future heart failure (HF) and cardiovascular (CV) death, even among individuals who meet the recommended levels of physical activity.

“Our research indicates that reducing sedentary time can lower the risk of cardiovascular issues. We found that spending 10.6 hours a day in sedentary activities may be a critical threshold associated with an increased risk of heart failure and cardiovascular mortality,” said Dr. Shaan Khurshid, a cardiologist at Massachusetts General Hospital and co-senior author of the study. “Excessive sitting or lying down can be detrimental to heart health, even for otherwise active individuals.”

Insufficient exercise is a well-recognized risk factor for cardiovascular disease (CVD). Current guidelines recommend 150 minutes of moderate-to-vigorous physical activity each week to support heart health. However, experts note that exercise constitutes only a small part of our daily activity. Additionally, the guidelines do not address sedentary behaviour, which is a much larger portion of our daily routines. This is noteworthy because evidence shows that sedentary behaviour is directly linked to an increased risk of CVD.

This study analyzed the levels of sedentary time linked to the greatest cardiovascular disease (CVD) risk and investigated how sedentary behavior and physical activity combined influence the likelihood of atrial fibrillation (AF), heart failure (HF), myocardial infarction (MI), and cardiovascular mortality.

The average age of the 89,530 study participants in the UK biobank was 62, and 56.4% were women. Participants submitted data from a wrist-worn triaxial accelerometer that captured movement over seven days. The average sedentary time per day was 9.4 hours.

After an average follow-up of eight years, 3,638 individuals (4.9%) developed incident AF, 1,854 (2.1%) developed incident HF, 1,610 (1.84%) developed indecent MI and 846 (0.94%) died of CV causes, respectively.

The effects of sedentary time varied by outcome. For AF and MI, the risk increased steadily over time without major shifts. For HF and CV mortality, the increase in risk was minimal until sedentary time exceeded about 10.6 hours a day, at which point risk rose significantly, showing a “threshold” effect for the behaviour.

For study participants who met the recommended 150 minutes of moderate-to-vigorous physical activity or more, the effects of sedentary behaviour on AF and MI risks were substantially reduced, but effects on the higher risk of HF and CV mortality remained prominent.

“Future guidelines and public health efforts should stress the importance of cutting down on sedentary time,” Khurshid said. “Avoiding more than 10.6 hours per day may be a realistic minimal target for better heart health.”

In an accompanying editorial comment, Charles Eaton, MD, MS, Director of the Brown University Department of Family Medicine, said the use of wearable accelerometers has shown that self-reporting significantly overestimates exercise and underestimates sedentary behavior.

Eaton said that replacing just 30 minutes of excessive sitting time each day with any type of physical activity can lower heart health risks. Adding moderate-to-vigorous activity cut the risk of HF by 15% and CV mortality by 10%, and even light activity reduced HF risk by 6% and CV mortality by 9%.

Posted on Cardiovascular disease

Breaking each hour with 10 mins of exercise significantly reduced blood pressure

Time spent sedentary beyond six hours per day during growth from childhood through young adulthood may cause an excess increase of 4 mmHg in systolic blood pressure, a new study shows. Continuously engaging in light physical activity (LPA) significantly mitigated the rise in blood pressure. The study was conducted in collaboration between the Universities of Bristol and Exeter in the UK, and the University of Eastern Finland, and the results were published in the prestigious Journal of Cachexia, Sarcopenia and Muscle.
A new study shows that sedentary time beyond six hours per day during growth from childhood through young adulthood may cause an excess increase of 4 mmHg in systolic blood pressure. Continuously engaging in light physical activity (LPA) significantly mitigated the rise in blood pressure. The study was conducted in collaboration between the Universities of Bristol and Exeter in the UK and the University of Eastern Finland, and the results were published in the prestigious Journal of Cachexia, Sarcopenia and Muscle.

In the present study, 2,513 children from the University of Bristol’s Children of the 90s cohort were tracked from age 11 to 24. At the beginning of the study, the children spent an average of six hours per day being sedentary, six hours engaged in light physical activity (LPA), and approximately 55 minutes in moderate-to-vigorous physical activity (MVPA). By the time they reached young adulthood, their daily habits had changed significantly: they spent nine hours per day sedentary, three hours per day in LPA, and about 50 minutes per day in MVPA.

The average blood pressure in childhood was 106/56 mmHg, which increased to 117/67 mmHg in young adulthood, partly due to normal physiological development. A persistent increase in sedentary time from ages 11 to 24 was associated with an average increase of 4 mmHg in systolic blood pressure. Engaging in light physical activity (LPA) from childhood helped to reduce the final blood pressure level by 3 mmHg; however, moderate to vigorous physical activity (MVPA) did not have any effect on lowering blood pressure.

“Moreover, a simulation model indicates that replacing just 10 minutes of sedentary time each hour with an equal amount of light physical activity (LPA) from childhood through young adulthood can lead to a decrease in blood pressure. Specifically, systolic blood pressure could drop by 3 mmHg and diastolic blood pressure by 2 mmHg. This finding is significant because research has shown that a reduction of 5 mmHg in systolic blood pressure can lower the risk of heart attacks and strokes by ten percent,” explains Andrew Agbaje, an award-winning physician and associate professor of Clinical Epidemiology and Child Health at the University of Eastern Finland.

The current study is the largest and the most extended follow-up of accelerometer-measured movement behaviour and blood pressure progression in youth worldwide. Blood pressure measurements, sedentary time, LPA, and MVPA were taken at the ages of 11, 15, and 24. The children’s fasting blood samples were also repeatedly measured for low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triglycerides, glucose, insulin, and high-sensitivity C-reactive protein. Heart rate, socio-economic status, family history of cardiovascular disease, smoking status as well as dual-energy X-ray absorptiometry measured fat mass and lean mass were accounted for in the analyses.

“We have earlier shown that elevated blood pressure and hypertension in adolescence increase the risk of premature cardiac damage in young adulthood. The identification of childhood sedentariness as a potential cause of elevated blood pressure and hypertension with LPA as an effective antidote is of clinical and public health significance. Several MVPA-based randomised controlled trials in the young population have not lowered blood pressure. We noted an MVPA-induced increase in muscle mass enhanced by a physiologic increase in blood pressure, explaining why earlier MVPA-based randomised clinical trials were unsuccessful,” says Agbaje.

“The World Health Organization estimates that 500 million new cases of physical inactivity-related non-communicable diseases would occur by 2030 and half would result from hypertension. At least three hours of LPA daily is critical to preventing and reversing elevated blood pressure and hypertension. LPA includes long walks, house chores, swimming, and bicycling. We all, parents, paediatricians and policymakers included, should encourage children and adolescents to participate in LPA to keep their blood pressure healthy,” Agbaje concludes.