Plastics

 

"I just want to say one word to you... just one word...Plastics."

 

One of the many great quotes from the 1967 film “The Graduate” finds the main character, Ben, floundering and undecided as to his future. His future father-in-law tries to guide him and suggests a career in plastics. Over the ensuing 57 years, he certainly would have been proven correct from the business standpoint. Plastics are everywhere. The worldwide production of plastic has grown from less than 2 million tons in 1950 to about 400 million tons in 2020. Plastic production is expected to double by 2040 and triple by 2060. While plastics have made our lives better there is a downside. Plastic waste is ubiquitous in the environment.  Plastic bottles, plastic wraps for food and other plastic products are dumped in the ocean and found in the soil. These plastic products break down into smaller particles called microplastics. Microplastics are picked up by fish, especially tuna, oysters, and mussels. The burning of plastics results in the release of microplastics into the air. Humans are exposed to microplastics by ingestion (for example by eating fish) or inhaling air laden with these particles. The Center for Disease Control suggests that microplastics are present in the bodies of nearly all Americans. Microplastics have been found in the colon, liver, spleen and lymph nodes. Now we find out that plastics are present in our arteries. 

 

A study from the March 7 2024 New England Journal of Medicine was eye opening and thought provoking. The researchers examined plaque from patients undergoing surgery for blockage in their carotid (neck) arteries. 304 patients had plaque removed and analyzed. In 58% of patients, microplastics were found in their arteries. Over the next 3 years, the patients who had microplastics in their blood vessels were 4 times more likely to die or have a heart attack or stroke compared to patients without microplastics. The proposed mechanism is that microplastics penetrate the cells in the blood vessel wall, producing chronic inflammation and resulting in worsening plaque production and outcomes. The authors proposed microplastics as a new cardiac risk factor. The study generated lots of discussion in the medical community. The study itself had many flaws (single center, small number of patients). The bottom line is association does not mean causation. Microplastics may be associated with adverse cardiac outcomes but may not be causing the adverse events. Further studies are needed to confirm the findings.

 

Plastics may be another in a growing number of environmental pollutants that have cardiovascular consequences. Known risk factors are air pollution (http://sportscardiology.blogspot.com/2017/08/paris-polluted-arteries-r-not-in-style.html)

and noise pollution 

(http://sportscardiology.blogspot.com/2020/02/the-cardiac-consequence-of-sound.html). Pollution is defined as the presence of a substance in the environment that can cause adverse health effects as well as damage to the ecosystem. Air pollution is the most important environmental cardiac risk factor. Of all of the air pollution related deaths, cardiac disease accounts for 45% of the total, while lung disease is only 8%. In addition, there is soil and water pollution due to farming and industrial activity as well as waste disposal (plastics falls into this category). In addition to plastics, other pollutants include pesticides and heavy metals. Despite different chemical compositions, pollutants lead to cardiovascular disease through common pathways. Pollutants trigger stress reactions leading to systemic inflammation leading to plaque and blockage in arteries, increased blood clotting, and abnormal hormonal secretion. 

 

Controlling pollution is important for overall cardiac health. Decreased air pollution over the past 50 years has contributed to the decline in overall cardiac mortality in that time period. Given the scope and magnitude of the pollution problem, what can a single person do? While most of the heavy work decreasing pollution must be left to governments and industry, there is much the individual can help with. To decrease exposure to air pollution one can stay indoors during high pollutant levels, commute by public transportation or bike or on foot and avoid spending time in high pollution areas, such as near highways. In addition, plastic pollution can be decreased by minimizing single use plastics (products designed for one use and then thrown away). This includes food and beverage containers, bottles, straws, cups, plastic forks and knives and disposable plastic bags. Follow some of these easy measures and your arteries will thank you. 

 

 

 

The Dawn of a New Day

 

When the child of morning, rosy-fingered Dawn, appeared, Odysseus rose and led the way to the place of assembly, which was near the ships.

Book VIII, The Odyssey

Homer

 

The phrase “rosy-fingered dawn” is an epithet (a descriptive term) used many times by Homer in both the Iliad and the Odyssey to say, “the break of day”. The term also signifies a fresh start to a new day and a tribute to the trials and tribulations of the day. How does the body handle the “rosy-fingered dawn” and rising from sleep to face a new day? What physiologic changes occur and how do those changes impact heart health?

 

The human body ticks to a 24-hour clock. This clock determines changes in our bodily functions which guide us between a rest stage (sleep) and an active stage. Our internal rhythms are synchronized with the world through interactions with light. These variations are called circadian rhythms (the term circadian is from Latin, circa which means around and dies which means day; around the day). As the rosy-fingered dawn breaks, we sense the presence of light. This results in the secretion of a number of hormones which serve to rouse us, “rev” us up, to get ready for a new day. The hormones include adrenaline and cortisol, which result in an increase in blood pressure and heart rate, increase our wakefulness, increase body temperature and get us ready to be become active. On the other hand, as light fades, the body secretes melatonin and decreases adrenaline and cortisol, getting us ready for the rest phase, sleep. Disruptions to the well-controlled circadian rhythm can lead to various chronic illnesses including heart disease. 

 

Circadian rhythms are controlled by a number of biological clocks. A central clock is located deep in the brain and regulates the clocks located throughout the body. These peripheral clocks are found in nearly all of the tissues of the body, especially in the gastrointestinal system, the nervous system, the liver and the heart. The circadian clocks are molecules within the cell that provide feedback loops timed to a 24-hour cycle. There are clocks in the heart muscle as well as in the wall of blood vessels. The heart muscle clocks orchestrate cellular processes, ensuring that they occur at the right time of the day. Growth and repair of heart tissue takes place during sleep or rest periods. If this circadian pattern is broken, then cardiac pathology ensues. During a normal day, there are fluctuations of up to 20% in various cardiac parameters. For example, blood pressure is lowest during sleep and highest in the early morning hours.  This is due to the release of the hormones responsible for rousing us at the beginning of the day.  Similarly, the greatest risk for a heart attack or stroke is around 6 AM. This is a direct result of the early morning changes with increased blood pressure and heart rate leading to increased stress with the heart’s blood vessels and an increase in clotting factors caused by the release of hormones. In addition, life threatening arrhythmias and sudden cardiac arrest peak around 6 AM.  

 

Maintaining normal circadian periodicity is important for preventing disease and maximizing longevity. Disruption of the normal circadian rhythm is detrimental and leads to a variety of chronic illnesses. Disruption can be genetic, environmental or behavioral. Irregular sleep and eating schedules misalign the clocks. It is important to keep sleep timed with lack of light, i.e. night-time. Irregular sleep schedules throw off the biological clocks so they can’t synchronize properly with the light-dark cycle. Changes such as jet lag and daylight savings time can disturb internal clocks and lead to cognitive impairment and increased risk for heart attack.  Shift workers who sleep during daytime are especially prone to circadian disturbances. Shift work is a risk factor for heart disease, diabetes, obesity and hypertension. It increases cholesterol and triglyceride levels and increase inflammation. Sleep timing is important as well. Evening types, people who have later wake up and bedtimes, are at increased risk compared to morning people. Evening types have a higher incidence of cardiac disease, diabetes and obesity. Therefore, it is important to keep a regular sleep schedule. Meal timing is another factor as food serves to synchronize the biological clocks. Eating late at night also leads to cardiac disease, diabetes, obesity and high cholesterol. Shifting food toward the beginning of the day reduces those risks. This was proven in a recent study. Late eaters, people whose largest meal of the day was after 12:38 PM, had higher risk for obesity than people whose main meal is at lunch time. Having smaller meals throughout the day was better than eating three “square” meals. In addition, intermittent fasting, food intake restricted to early morning to 6 PM with an overnight fast, can reduce weight and protect against metabolic disease. 

 

To every rule, there is an exception. In this case, the exception lies in a Blue Zone. Blue Zones are areas around the world where there is exceptional longevity, with many people in the population reaching 100 years of age. Blue Zones have been identified in Japan, Costa Rica, California and on the Mediterranean island of Ikaria, Greece. The Mediterranean lifestyle seems to counter the circadian rhythms noted above. Dinner is served after 9 PM at night and bedtime occurs late as well. In addition, there is a day time siesta, so sleep patterns are irregular. On the other hand, the main meal is lunch. 

 

There are numerous factors involved in greeting many rosy-fingered dawns. Listening to our biologic clocks and following our circadian rhythms can help stave off disease and increase longevity. In order to do this, regular sleep habits and timing sleep patterns to light and dark seem prudent. In addition, shifting caloric intake to earlier in the day, eating smaller meals and doing some overnight fasting will improve the chances of seeing the dawn of a new day. 

 

 

Cold-Hearted

 

CLEOPATRA: Ah, dear, if I be so,
From my cold heart let heaven engender hail,
And poison it in the source

 

The expression cold-hearted means showing no understanding, no feeling towards another. It is unsympathetic, unemotional, uncaring and cruel. If used in a sentence it might look like this: “The cold-hearted landlord evicted the poor family with a sick child”. The first known use of the adjective cold-hearted is in Shakespeare’s play, “Antony and Cleopatra”. Certainly, Cleopatra could be considered cold-hearted due to her various plots to overthrow her brother and rule Egypt. Heart attacks can also be considered cold-hearted. A heart attack does not discriminate; it can affect men or women, young or old, rich or poor. It can strike at any time of the day or night, often without warning. Despite that, heart attacks do have some predictable variation. For example, heart attack risk changes with the season of the year and is associated with extremes of temperature, both hot and cold.  The only known example of Cleopatra’s handwriting is a single Greek work, γίνεσθοι, which she wrote on a papyrus addressed to a tax collector in 33 BC. It translates to, “so be it” or “make it happen”. Heeding the queen’s order, we will now “make it happen” and outline when heart attacks are the most cold-hearted.  

 

A heart attack occurs when a plaque in a heart artery breaks open. When the blood is exposed to foreign material (such as an exposed plaque), it does what it is supposed to do and forms a blood clot within the artery. If the clot totally obstructs the flow of blood, the type of resulting heart attack is called a STEMI (ST elevation myocardial infarction). If there is still some residual blood flow through the blockage and clot, then the heart attack is a nonSTEMI. For both types of heart attack, there is a U-shaped association with temperature. There is an increased risk for heart attack on very cold and on very hot days. Since we are in the throes of winter, we’ll concentrate on the cold weather effects on the heart. An increase in heart attacks and heart attack deaths in the winter was first noticed in the 1930’s. A large database studied heart attacks from the 1980’s and 1990’s and quantified the risk. A seasonal distribution was confirmed; there were 50% more heart attacks in the winter months compared to the summer time. The peak number of cases were in January, followed by February, March, November and December. Another series, also from the 1990’s, concluded that coronary events were 20-40% more likely to happen in the winter and spring versus other times of the year. One other study (1980’s-1990’s) also showed that the month with the highest mortality rate due to a heart attack was January.  Lastly, a study from Minnesota (1979-2002) showed that a temperature below 0 degrees Celsius (32 degrees Fahrenheit) was strongly associated with death due to a heart attack.

 

A lot has changed in the 25 to 30 years since this data was reported. At least two factors have changed significantly. First, heart attack care has vastly improved. Catheterization and coronary stenting during the acute event (especially STEMI) restores blood flow and subsequently fewer patients die from their heart attack. Secondly, there is global warming. Since the 1950’s each decade is hotter than the previous one. Globally, the temperature has risen 0.17 degrees Fahrenheit each decade, with steeper rise since the 1970’s. Has the combination of warmer weather and improvement in cardiac care reduced the risk for having a heart attack in winter? To answer this a group from Germany looked at temperature and heart attacks in two distinct periods, 1987 to 2000 and 2001 to 2014. During those time periods, the average daily maximum temperature rose from 14.5 degrees C (58.1 degrees F) during 1987-2000 to 15.1 degrees C (59.2 degrees F) in 2001-2014. They found no significant decline in cold related heart attacks when comparing the two eras. Heart attack risk remained high with very cold temperature. Another group studied data from five European countries between 1994 and 2010. They also found that cold weather was associated with an increased risk for heart attack, without change over time. With a drop in temperature from 5 degrees C (41 degrees F) to – 5 degrees C (23 degrees F) there is about 20% increased risk for heart attack and cardiac death. Lastly, a study from Taiwan looking at data from 2000 to 2017 showed that below 15 degrees C (59 degrees F), every 1 degree drop in temperature increased the risk for heart attack by 0.9%.

 

The relationship between cold weather and heart attack has been seen across the globe, in different eras, with different populations and with different weather conditions. It even holds up locally. Over the past five years, the month with the second highest risk for STEMI at Robert Wood Johnson Somerset has been January. How does cold affect the heart and who is at risk?   Elderly patients (over 65 years old) are more susceptible to cold related heart attacks than younger people. The highest risk are older patients with hypertension (high blood pressure). Cold weather increases blood pressure and causes spasm of the heart arteries. This leads to an increase in the work load of the heart. Cold weather increases the thickness of the blood, increases clotting factors and increases inflammation. All of the factors can cause a vulnerable heart plaque to open and trigger a heart attack. The winter months also increase the risk for respiratory infections (for example, flu) which act as a trigger for a heart attack. Other cold related factors include less physical activity, weight gain and holiday stress adding to the risk for heart attack in the winter. 

 

For the elderly heart patient, the cold weather can be as deadly as an asp. For those with significant heart disease, here are some cold weather recommendations. Skip strenuous activity outdoors when the temperature (or the wind chill) is below 30 degrees F and do your exercising indoors. When outside, try to cover all exposed skin. Make sure the heating system in the house is working and use it! The World Health Organization suggests keeping the indoor temperature above 68 degrees F. Lastly, relax with a cup of tea by the fire and count the days until spring. 

 

 

 

 

Vive La Resistance (Training)!

 

The holidays are over. It’s a new year. The decorations are stored away and the New Year’s resolutions are made. What are the top New Year’s resolutions? According to Forbes magazine, the number one New Year’s resolution for 2024 is to improve fitness and exercise more. That is a worthy goal, but what type of exercise should be targeted in 2024? Another top resolution per Forbes is to lose weight. That is also a good goal, but how long will it take to get the holiday weight off?

 

If you are feeling bloated and have gained weight during this holiday season, you are not alone. A study tracked the change in weight for participants in three countries, the US, Germany and Japan. In these three diverse countries, weight started to go up in November and peaked on New Year’s Day. On average, it took until March to lose the weight gained and get back to the pre-holiday weight. How can holiday weight gain be prevented? One strategy is to have smaller meal portions at the family table and eat fewer desserts. Another is to exercise. It has been shown that people who continue exercise training during the holidays can prevent weight gain.

 

It is established that exercise will help with losing weight. It is established that exercising more is the top New Year’s resolution, but what kind of exercising should be done? Aerobic training has well known benefits. The scientific evidence is vast and consistent in showing that cardio exercise (such as running, cycling, swimming or hiking) has many cardiovascular benefits, in addition to increasing longevity. Therefore, aerobic exercise should be a main component of any exercise regimen. What about resistance training? It has been perceived that aerobic exercise is better than resistance training but in fact each is important. It has been estimated that only 28% of US adults perform any form of resistance exercise. Resistance training lowers the risk of dying from any cause by 15% and lowers the risk for cardiovascular disease and death by 17%. Resistance exercise will lower systolic blood pressure by 4 mmHg and diastolic blood pressure by 2 mmHg. It will lower fasting blood sugar by 2 to 5 mg/dl, increase HDL cholesterol (2 to 12 mg/dl), lower total cholesterol (by 8 mg/dl) and reduce triglycerides (7 to 13 mg/dl). Combining resistance and aerobic training gives even greater benefit in terms of weight reduction, diabetes prevention, cholesterol lowering, cardiovascular disease prevention and mortality reduction. 

 

In addition to cardiovascular prevention, resistance training has another very important benefit. As we age, there is progressive decrease in muscle mass and strength. With age, activities such as standing up, sitting down, climbing stairs and maintaining balance are as important as cardiac fitness.  Most of the loss of muscle mass occurs after age 60. Men will lose, on average, 33% of their muscle mass between the ages of 60 and 97. Women will lose 26%. With the loss of muscle mass and strength, significant health problems may ensue as the risk for falls increases by 60% and risk of bone fracture increases by 84%. Resistance training helps to build and maintain muscle strength. Resistance training improves muscle mass (by increasing leg and total body musculature) and muscle strength (by improving handgrip strength, chest and leg press) as well as overall physical performance (by improving sitting to standing, walking speed). 

 

What does a resistance training prescription look like? Resistance training can include free weights, body weight (for example push-ups, squats), machine weights or resistance bands. Resistance training doesn’t necessarily lead to “bulking up” and can be done without great expense (a gym membership or a major set of weights aren’t needed). Ideally 8 to 10 different exercises involving major muscle groups are done (for example, push-up, squat, abdominal crunch, biceps curl). Each exercise is performed for 8 to 12 repetitions. Weight and intensity can be increased gradually over time. Resistance training should be done two or more times per week for maximal muscle strengthening and cardiovascular benefit. 

 

As we get older, we are limited by our heart and/or our orthopedics. Resistance exercise helps with both. So this year resolve to pump up your fitness, build some muscle, lose weight and improve your cardiovascular profile by incorporating resistance training into your exercise routine.