Cold Weather and CVD Risk
Summer's here and so is the heat. Last week on the day that I read about this study it was 91 degrees Fahrenheit and 57% humidity in my surroundings, and I found myself thinking about winter heart attacks. This is because of a research announcement that may explain why there is an increase in cardiovascular disease (CVD) related deaths in the winter months. Apparently cold weather stimulates inflammation in the body, a factor that was demonstrated in the levels of inflammatory markers in the blood in the study subjects.
In this study researchers observed that 5 consecutive days of colder weather lead to an immediate increase in levels of the inflammatory markers C-reactive protein (CRP) and interleukin-6; levels of a third marker of inflammation, called fibrinogen, rose 3 days later than the other two markers. The research team measured levels of these markers in nearly 6,000 blood samples from 1,000 adults who had had a heart attack within the last 6 years. These adults were located across a wide range of climate zones.
The study, reported in the May issue of Epidemiology, suggests that one mechanism by which cold weather increases cardiovascular mortality is by increasing the body's inflammatory response. The investigators report that a 10 degree decrease in Celsius temperature (1 °C = 1.8 °F, so 10 x 1.8= 18 degrees F) over a 5 day average temperature before subjects blood was tested resulted in a 4% increase in CRP, a 3.3% increase in interleukin-6, and a 1.3% increase in fibrinogen levels in the blood.
The researchers suggest that this may indicate a biological mechanism for the observed seasonal increase in death from heart disease and stroke in the elderly. Since it is known that cold temperatures increase blood pressure and this leads to additional strain on the heart, this increase in inflammation may be an additional risk factor in patients already susceptible to cardiovascular events. Since fibrinogen is directly involved in clotting in acute heart events, cold stress may be a trigger that leads to events that thicken the blood, making clots more likely.
This is interesting research that needs additional study, since it is my understanding that we still aren't sure whether the CRP factor arrives as a marker of increased CVD risk or appears only after CVD is established. Despite this information, I'd given anything for an 18 degree drop in Fahrenheit temperature at the moment, but I guess I'll have to settle for a cold glass of iced tea!
Take care,
Laurie
Related Topics: Technorati Tags: heart disease, inflammation, C-reactive protein, CVD, cold weather, heart health
In this study researchers observed that 5 consecutive days of colder weather lead to an immediate increase in levels of the inflammatory markers C-reactive protein (CRP) and interleukin-6; levels of a third marker of inflammation, called fibrinogen, rose 3 days later than the other two markers. The research team measured levels of these markers in nearly 6,000 blood samples from 1,000 adults who had had a heart attack within the last 6 years. These adults were located across a wide range of climate zones.
The study, reported in the May issue of Epidemiology, suggests that one mechanism by which cold weather increases cardiovascular mortality is by increasing the body's inflammatory response. The investigators report that a 10 degree decrease in Celsius temperature (1 °C = 1.8 °F, so 10 x 1.8= 18 degrees F) over a 5 day average temperature before subjects blood was tested resulted in a 4% increase in CRP, a 3.3% increase in interleukin-6, and a 1.3% increase in fibrinogen levels in the blood.
The researchers suggest that this may indicate a biological mechanism for the observed seasonal increase in death from heart disease and stroke in the elderly. Since it is known that cold temperatures increase blood pressure and this leads to additional strain on the heart, this increase in inflammation may be an additional risk factor in patients already susceptible to cardiovascular events. Since fibrinogen is directly involved in clotting in acute heart events, cold stress may be a trigger that leads to events that thicken the blood, making clots more likely.
This is interesting research that needs additional study, since it is my understanding that we still aren't sure whether the CRP factor arrives as a marker of increased CVD risk or appears only after CVD is established. Despite this information, I'd given anything for an 18 degree drop in Fahrenheit temperature at the moment, but I guess I'll have to settle for a cold glass of iced tea!
Take care,
Laurie
Related Topics: Technorati Tags: heart disease, inflammation, C-reactive protein, CVD, cold weather, heart health
1 Comments:
So far, the best medication to reduce CVD risk is niacin, which is more affordable than aspirin.
Unfortunately, the Big Pharma has raised specious safety concerns re: niacin. They have over emphasized niacin's side-effects while minimizing the more serious side-effects of the profitable, statin drugs. See http://www.cholesterolscore.com/?p=69
Judging from the recent scramble by Big Pharma to, somehow, cash in on the only medication (niacin) that moves all the blood/lipid numbers in the right directions, I'd say that most of the info at cholesterolscore.com may be accurate. What do you think?
Post a Comment