Tuesday, November 27, 2007

Global Warming May Trigger Rise in Heart Deaths

The fact that there are many more health problems in winter than in summer must not be mentioned of course. Both warm and cold weather can have their problems but, on balance, warm weather is better for you. People in frail health don't usually go to Iceland. They go to warmer places. But I guess we ought to feel sorry for all those elderly people who retire to Florida. The government should FORCE them to go to Alaska instead -- for their own good, of course

Soaring temperatures and high ozone levels work together to boost death risks from heart disease and stroke, researchers report. They believe that global warming -- which brings more heat and more ozone -- may further increase the number of people who die of cardiovascular events. "Temperature and ozone are strong factors in cardiovascular mortality during June to September in the Unites States," noted the study's lead author, Cizao Ren, from the Department of Epidemiology in the School of Medicine at the University of California, Irvine. "Temperature and air pollution combine to affect the health of large populations," he added. Ren expects the problem will get worse as the earth becomes hotter. "Increases in temperature and air pollution will have a strong affect on health," he said.

His team based its findings on data on almost 100 million people living in 95 different areas across the United States from June to September. These Americans were included in the National Mortality and Air Pollution Study, which tracked links between health and air pollution for the years 1987 to 2000. Four million deaths from heart attacks or strokes occurred during the study period. Ren's team compared death rates against changes in temperature during one day.

Ozone was a common link, they found. In fact, the higher the ozone level, the greater the risk of cardiovascular death attributable to high temperatures, Ren's team concluded. Ozone levels ranged from an average of 36.74 parts per billion to 142.85 parts per billion, while daily temperatures ranged from 68 to around 107 degrees Fahrenheit. When the ozone level was at its lowest, a 10-degree increase in temperature was associated with about a 1 percent increase in deaths from heart disease and stroke. However, when the ozone level was at its highest, there was a more than an 8 percent increase in deaths from heart disease and stroke, Ren's group found.

The findings are published Nov. 21 in the online edition of the journal Occupational and Environmental Medicine. Ozone is a pollutant strongly linked to weather conditions, particularly the amount of ultraviolet light in the atmosphere. Ozone is generated by a reaction between airborne nitrogen oxides, volatile organic compounds, and oxygen in sunlight. Exposure to high levels of ozone can affect the airways and the autonomic nervous system, making people more susceptible to the effects of temperature changes, Ren's team explained.

One expert agreed with the team's conclusions. "This paper reinforces what we know -- that both temperature and ozone affect health, even to the extent that they affect mortality," said George Thurston, an associate professor of environmental medicine at New York University. Global warming will increase both temperatures and pollution, Thurston added, because higher temperatures are conducive to the production of ozone. "This will be a growing problem," he said. For the general public, the study raises questions about pollution and climate change, Thurston said. "The health effects may be even worse than thought," he said. "There are health benefits to reducing climate change." Cutting back on the use of fossil fuels will help, Thurston said. "Reducing fossil fuel combustion will reduce climate change and pollution," he said. "We have seen the problem, and it's fossil fuel combustion. Now, all we have to do is come up with an alternative," he said.



Amazing stuff you get in the medical literature sometimes. The study below proves that more active parents tend to have more active children. Who would have thought? Is the deteriorated quality of the BMJ becoming so well known that lightweight submissions like this are needed to fill their pages?

Note also that the speculative last sentence below shows that the authors do NOT believe that personality characteristics are genetically transmitted -- despite the overwhelming evidence from the behaviour genetics literature showing that they are. The BMJ seems to have become a propaganda sheet for some weird Leftist cult rather than a worthwhile medical journal

Early life determinants of physical activity in 11 to 12 year olds: cohort study

By Calum Mattocks et al.

Objective: To examine factors in early life (up to age 5 years) that are associated with objectively measured physical activity in 11-12 year olds.

Design: Prospective cohort study.

Setting: Avon longitudinal study of parents and children, United Kingdom.

Participants: Children aged 11-12 years from the Avon longitudinal study of parents and children.

Main outcome measure: Physical activity levels in counts per minute (cpm) and minutes of moderate to vigorous physical activity for seven days measured with a uniaxial actigraph accelerometer.

Results: Valid actigraph data, defined as at least three days of physical activity for at least 10 hours a day, were collected from 5451 children. Several factors were associated with physical activity at ages 11-12 years. Regression coefficients are compared with the baseline of "none" for categorical variables: maternal brisk walking during pregnancy (regression coefficient 5.0, 95% confidence interval -8.5 to 18.5; cpm for <1 h/wk and ~ 2 h/wk of physical activity 24.2, 7.8 to 40.7), parents' physical activity when the child was aged 21 months (28.5, 15.2 to 41.8 and cpm of physical activity for either parent active and both parents active 33.5, 17.8 to 49.3), and parity assessed during pregnancy (2.9, -7.6 to 13.4 and cpm of physical activity for 1 and ~ 2 parity 21.2, 7.1 to 35.3).

Conclusions: Few factors in early life predicted later physical activity in 11-12 year olds. Parents' physical activity during pregnancy and early in the child's life showed a modest association with physical activity of the child at age 11-12 years, suggesting that active parents tend to raise active children. Helping parents to increase their physical activity therefore may promote children's activity.

BMJ, 23 November 2007


Just some problems with the "Obesity" war:

1). It tries to impose behavior change on everybody -- when most of those targeted are not obese and hence have no reason to change their behaviour. It is a form of punishing the innocent and the guilty alike. (It is also typical of Leftist thinking: Scorning the individual and capable of dealing with large groups only).

2). The longevity research all leads to the conclusion that it is people of MIDDLING weight who live longest -- not slim people. So the "epidemic" of obesity is in fact largely an "epidemic" of living longer.

3). It is total calorie intake that makes you fat -- not where you get your calories. Policies that attack only the source of the calories (e.g. "junk food") without addressing total calorie intake are hence pissing into the wind. People involuntarily deprived of their preferred calorie intake from one source are highly likely to seek and find their calories elsewhere.

4). So-called junk food is perfectly nutritious. A big Mac meal comprises meat, bread, salad and potatoes -- which is a mainstream Western diet. If that is bad then we are all in big trouble.

5). Food warriors demonize salt and fat. But we need a daily salt intake to counter salt-loss through perspiration and the research shows that people on salt-restricted diets die SOONER. And Eskimos eat huge amounts of fat with no apparent ill-effects. And the average home-cooked roast dinner has LOTS of fat. Will we ban roast dinners?

6). The foods restricted are often no more calorific than those permitted -- such as milk and fruit-juice drinks.

7). Tendency to weight is mostly genetic and is therefore not readily susceptible to voluntary behaviour change.

8). And when are we going to ban cheese? Cheese is a concentrated calorie bomb and has lots of that wicked animal fat in it too. Wouldn't we all be better off without it? And what about butter and margarine? They are just about pure fat. Surely they should be treated as contraband in kids' lunchboxes! [/sarcasm].

9). And how odd it is that we never hear of the huge American study which showed that women who eat lots of veggies have an INCREASED risk of stomach cancer? So the official recommendation to eat five lots of veggies every day might just be creating lots of cancer for the future! It's as plausible (i.e. not very) as all the other dietary "wisdom" we read about fat etc.

10). And will "this generation of Western children be the first in history to lead shorter lives than their parents did"? This is another anti-fat scare that emanates from a much-cited editorial in a prominent medical journal that said so. Yet this editorial offered no statistical basis for its opinion -- an opinion that flies directly in the face of the available evidence.

Even statistical correlations far stronger than anything found in medical research may disappear if more data is used. A remarkable example from Sociology:
"The modern literature on hate crimes began with a remarkable 1933 book by Arthur Raper titled The Tragedy of Lynching. Raper assembled data on the number of lynchings each year in the South and on the price of an acre's yield of cotton. He calculated the correla-tion coefficient between the two series at -0.532. In other words, when the economy was doing well, the number of lynchings was lower.... In 2001, Donald Green, Laurence McFalls, and Jennifer Smith published a paper that demolished the alleged connection between economic condi-tions and lynchings in Raper's data. Raper had the misfortune of stopping his anal-ysis in 1929. After the Great Depression hit, the price of cotton plummeted and economic condi-tions deteriorated, yet lynchings continued to fall. The correlation disappeared altogether when more years of data were added."
So we must be sure to base our conclusions on ALL the data. But in medical research, data selectivity and the "overlooking" of discordant research findings is epidemic.


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