Air temperatures are rising!!!

How Does Hot Weather Affect Our Body, Who is at Risk?

High temperatures in summer pose a risk, especially for people over 50 years of age, overweight or with heart disease. Complaints in people with known heart disease may increase with hot weather, and if patients do not take the necessary precautions, they may experience serious problems.
Due to extremely hot weather, humidity and sweating, fluid and salt loss occurs in the body. On days when hot weather makes itself felt seriously, experts recommend that you should not stay under the sun for a long time. It is very important, especially for those with chronic diseases, to be extremely careful in hot weather.

Summer heat can create critical problems for every person. The body works to maintain its normal temperature in hot weather, which is especially dangerous for people over the age of 50, overweight people and those with heart disease. Sweating is an effort to distribute the heat of the skin evenly throughout the body. This effort increases heart rate and causes blood pressure to drop, placing additional strain on the cardiovascular system. This burden can cause worsening symptoms in people with known heart disease. For example, chest pain may begin in a person with cardiovascular disease, or shortness of breath may develop or increase in someone with heart failure.

Who are at risk?

The groups most affected by extreme heat are:

• Elderly people aged 65 and over who live alone,
• Children under 3-4 years old,
• Those who need medical care,
• Pregnant women,
• Those who work outdoors under the sun,
• Those who are overweight or overweight,
• Those with chronic diseases (diabetes, cardiovascular diseases, cerebrovascular diseases, psychological diseases, chronic respiratory system diseases, liver diseases, oncology patients, kidney diseases)
• People who constantly use medications (especially blood pressure reducers, diuretics, depression and sleeping medications),
• Street children and homeless people.
• People with high age, pregnancy and underlying chronic diseases constitute the highest risk group.

Exposure to high temperatures increases the risk of acute cardiovascular diseases such as myocardial infarction and heart attack. In general, cardiovascular diseases are the primary cause of death in hot weather. Another meta-analysis conducted in 2018 concluded that every 1 °C increase in temperature increases the risk of heart attack by 1.6%.

Patients with heart failure tend to lack the ability to compensate for the increased cardiovascular demands caused by heat exposure. Increased cardiac strain can cause arrhythmias, peripheral edema, and even sudden death.

Older people's vulnerability to heat can be attributed in part to comorbidities, polypharmacy, and decline in thermoregulatory function, such as reduced skin blood flow and sweat rate.
Pregnant women are at higher risk during heat exposure due to body weight gain and increased heat production from the metabolic demands of the growing fetus. Exposure to high temperatures in pregnant women is associated with adverse outcomes, including premature birth, low birth weight, stillbirths, and congenital heart diseases.

In the occupational environment, prolonged heat exposure and intense physical work can lead to greater heat stress for workers, even at lower temperatures.
Night temperatures have significant effects on your sleep quality. Findings from a recent study suggest a link between warm nights and mortality.

The health effects of heat often occur within a week after a heat event.

Mechanisms of the Effect of Temperature

In case of exposure to high temperatures, skin blood flow and sweating increase to lower body temperature. The sympathetic nervous system is activated to maintain cardiac output. The resulting peripheral vasodilation and dehydration may also cause decreases in blood pressure.

As a result of heat stress, hemoconcentration and sweating, a prothrombotic state occurs due to decreased plasma volume and an increase in circulating platelets, red blood cells and blood viscosity levels. The release of cytokines such as interleukin 1 and interleukin 6, which modulate local and systemic inflammatory responses and can lead to endothelial dysfunction, increases.

Reduced splanchnic (blood flow to the gastrointestinal organs in the abdomen, including the stomach, liver, spleen, pancreas, small intestine, and large intestine) blood flow to maintain blood pressure results in gastrointestinal ischemia and increased intestinal permeability, followed by an increased risk of bacterial infection.

Heart patients should be careful with their medications and seek doctor's advice in hot weather!
Temperature has been shown to have potential interactions with cardiovascular medications. It can affect the absorption, distribution and elimination of the drug, on the one hand, and the therapeutic response of the drug, on the other hand.

In addition, temperature can affect the human body's adaptation mechanisms, leading to an increased risk of drug side effects. For example, temperature-induced vasodilation can significantly enhance the blood pressure-lowering effects of cardiovascular drugs. This can cause serious injuries and even increase the risk of syncope and MI.

Diuretics, commonly prescribed for patients with hypertension or heart failure, may exaggerate the adverse effects of heat by causing dehydration and electrolyte imbalance.

What is heat stroke?

Heatstroke, also known as sunstroke, is a condition that occurs when the body overheats due to exposure to high temperatures for a long time. Our body has various mechanisms to protect itself against temperature increases. The human body responds to heat stress in two primary ways:

1) vasodilation to further increase blood flow towards the skin to improve heat transfer from the muscles to the skin and then to the environment, and,
2) evaporation following sweat secretion through the skin and balancing body temperature. Body temperature varies between 36.3-37.1°C in order to maintain normal functions under physiological conditions, rising above 39.5°C can cause significant functional damage, and rising above 42°C is considered fatal. Sweating is a very useful physiological mechanism in maintaining normal body temperature.

The heat generated in the body due to sweating is eliminated through the skin. Wetness due to sweat on the skin evaporates with the heat it receives from the body, cooling the body. Directing and increasing blood flow to the skin due to the expansion of the vessels in the skin reduces the filling pressure of the heart and increases the blood demand of the heart. Who is at risk? In conditions where physiological protection mechanisms are not yet sufficiently developed (infants, early childhood, etc.) or their function decreases (old age, chronic disease, etc.), the increase in ambient temperature causes an uncontrolled increase in temperature in the body (40°C and above). If there is not enough sweating or there is high humidity in the environment, body temperature can rise to dangerous levels that cannot fulfill physiological functions.

In conditions where physiological protection mechanisms are not yet sufficiently developed (infants, early childhood, etc.) or their function decreases (old age, chronic disease, etc.), the increase in ambient temperature causes an uncontrolled increase in temperature in the body (40°C and above). If there is not enough sweating or there is high humidity in the environment, body temperature can rise to dangerous levels that cannot fulfill physiological functions.

• Elderly people: While it is at risk for people over the age of 50, the risk increases even more especially for those over the age of 75.
• Gender: It is known that men are slightly more sensitive than women.
• Babies and children under 5 years of age: Their physiological protective mechanisms against heat are not sufficiently developed.
• Those with comorbidities: Those with almost all chronic diseases are more affected by temperature increases. Especially those with diseases such as cardiovascular system diseases, Parkinson's disease, dementia, obesity, diabetes, diarrhea, cystic fibrosis, scleroderma, bedridden patients and those who have had heat stroke before are at greater risk.
• Those with lung disease: It may cause an increase in symptoms (cough, sputum, wheezing, shortness of breath, etc.) and exacerbations in people with a long-term lung disease such as asthma, bronchiectasis or COPD. Strong sunlight causes ozone levels in the air to rise and other air pollutants can trigger this. Humid air can also worsen respiratory effects. Summer is also the time when pollen levels of grasses and weeds rise.
• Using medication: Those using antihypertensives, beta blockers, diuretics, antidepressants, and antipsychotic medications are at risk.
• Living conditions: Homeless people, the poor, people working outdoors (agricultural and construction workers, etc.), and people who do not have the opportunity to go to a cooler place are at risk. The risk of exposure to heat increases in urban centers due to the heat island effect and on the top floors of apartment buildings and in houses made of brick. In addition, there are claims that houses that can be air conditioned (cooled with air conditioners) protect against the effects of heat, but disrupt physiological mechanisms in the long term.
• Air pollution: During the summer months when heat waves are observed, there is ozone pollution and particulate matter pollution, especially in urban areas. The negative effects of ozone-related air pollution and temperature increase on human health are stronger.
• Working life: Occupational risk factors include heavy physical activity, hot environmental conditions, lack of heat acclimatization and wearing clothing that traps body heat. According to International Labor Organization (ILO) data, it is estimated that more than 1 billion workers are exposed to high temperatures. Many workers are exposed to repeated daily occupational heat stress for long periods of time, making them more susceptible to both acute and chronic effects of heat stress. According to United States Occupational Safety and Health Administration (OSHA) data, most outdoor deaths (50-70%) occur in the first few days of work in warm or hot environments; because the body must gradually build a tolerance to heat (heat acclimatization). Workers in agriculture, construction (especially road, roofing and other outdoor work), cleaning, transportation, mail and package delivery, landscaping, oil and gas well operations, traffic police, soldiers, athletes who are directly exposed to hot weather, especially outdoors They may be more susceptible to heat stroke. Increasing environmental temperature and humidity causes problems by increasing the load on the circulatory system of employees, especially in jobs such as carrying and lifting loads. It is projected that by 2085, very few major cities will be able to host the Summer Olympics due to heat-related risks to athletes. Heat concerns may be even greater for the Paralympics; because there are more sensitive groups. The ambient temperature must be suitable for people to work efficiently. For people who work in hot conditions and sweat, it is important to take frequent breaks and consume sports drinks or electrolyte solutions to replenish potassium, sodium and other minerals lost through sweating.

Nutrition and Hydration

Even if there is no feeling of thirst, at least 2-2.5 liters (12-14 glasses) of liquid should be consumed every day.

Breakfast should include low-fat cheeses, olives and fresh vegetables, and milk, fruit juice, herbal teas such as linden and rosehip should be preferred instead of drinks containing caffeine.
Consumption of fatty foods and fried foods should be avoided; Vegetable oils should be used in meals. When cooking food, healthy cooking methods such as boiling, grilling, cooking in its own juice or in a little water should be used instead of frying and roasting.
Plenty of vegetables and fruits should be consumed to increase body resistance and ensure that the body receives sufficient vitamins and minerals.

More fluids than usual should be consumed to prevent increased fluid and mineral loss through sweating.

Although drinking water is essential for fluid intake, beverages such as milk, ayran and fruit juice should be preferred instead of coffee, tea and carbonated drinks for non-water fluid intake. If fluid intake is restricted by the doctor or diuretic medication is used, it is necessary to consult the relevant doctor.

Very cold and icy drinks should not be preferred as they may cause stomach cramps.
Caffeine, alcohol and drinks containing high amounts of sugar should not be consumed as they cause more fluid loss from the body.

Consumption of foods sold outside and in the open should be avoided, foods that are at risk of rapid spoilage (meat, eggs, milk, fish, etc.) should not be kept in the open, and hygiene rules should be taken into consideration during the preparation and cooking of foods.

Ways to Protect from Heat;

• Unless necessary, one should not go out during the hours when the sun rays are strongest (between 10:00 in the morning and 15:00 in the afternoon). Children, the elderly, and those with chronic diseases such as heart disease and diabetes should pay particular attention to this.
• Care should be taken to ventilate closed areas and ensure adequate air flow.
• Plenty of liquid and mineral-containing drinks should be consumed. Salt intake should be increased with foods, except for people with heart disease or hypertension who are on a salt-free diet. Those with salt restriction should be very careful about fluid and salt loss.
• Drinks containing alcohol should not be consumed to cool down. These first cool you down and then increase the body's water loss.
• Light meals, juicy foods (fruit, salad, soup, etc.) should be eaten.
• Fatty, heavy meals and overeating should be avoided.
• Thin, light-coloured, loose-fitting clothes should be worn. Clothing should protect the person from sunlight, but should not cause sweating or dehydration.
• If we are in the sun, a wide-brimmed, light-coloured hat should be worn and the face should not be directly under the sun.
• Shower should be taken as often as possible.
• No living creature should be left in a closed or parked vehicle in extreme temperatures.
• Those who work actively outdoors should not remain unprotected under the sun whenever possible and should avoid heavy exertion.
• You should know the symptoms of heat stroke and exhaustion and be careful against these symptoms. If the patient does not improve with the measures taken, a hospital should be applied.