Swine Flu is a killer for the realy fat guys

Swine Flu Packs Bigger Jolt for Obese as ‘Striking’ Link Found
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By Jason Gale

July 11 (Bloomberg) -- Extremely fat swine flu sufferers may have a tendency to become severely ill, health officials in the U.S. and Europe said, after a report showed a “striking” prevalence of obesity among patients hospitalized in Michigan.

Nine of 10 patients with the pandemic flu strain admitted to an intensive care unit at Ann Arbor from late May to early June, were obese and seven were “extremely obese,” with a body mass index of at least 40, doctors said. Three of the 10 died and seven had no other known health problems.

The study, in the Morbidity and Mortality Weekly Report yesterday, supports a pattern seen by doctors tracking the pandemic in hospital reports from Glasgow to Melbourne and from Santiago to New York. Researchers say the trend is surprising because obesity hasn’t been identified previously as a risk factor for severe complications of seasonal flu.

“Clinicians should be aware that severe illness and fatal outcomes also can occur in patients without known risk factors for complications of seasonal influenza, including persons with extreme obesity,” the Centers for Disease Control and Prevention in Atlanta said in an editorial note accompanying its report.

With the new virus on a collision course with the obesity epidemic, the World Health Organization says it’s gathering statistics to confirm and understand this development.

“Morbid obesity is one of the most common findings turning up in severely ill patients,” said Nikki Shindo, who is leading the investigation of swine flu patients at the WHO in Geneva. “It’s a huge problem.”

Seeking More Answers

So far, the evidence is anecdotal. No global or national data have been reported and the CDC said it’s unknown whether obesity is an independent risk factor. Yesterday, the European Centre for Disease Control and Prevention in Stockholm began including obesity on a list of factors that put patients at risk of dying from the pandemic bug.

Drugmaker Roche Holding AG is combing through studies to determine whether heavier people should get bigger doses of its Tamiflu antiviral. The CDC said yesterday that, until more data are available, a double dose of the Roche pill or a longer course of treatment can be considered for severely ill hospitalized swine flu patients.

The pandemic strain is reported to have killed 429 people worldwide since its discovery in the U.S. and Mexico in April, according to the WHO’s most recent report. The infection, which has spread as far as New Zealand and Norway, causes little more than a fever and cough in most cases. The majority of those who died were pregnant, had asthma, diabetes or other chronic diseases, according to the WHO.

Obesity ‘Stands Out’

“About 75 percent of patients have underlying conditions, and clearly obesity stands out as a statistically significant factor involved in the seriousness of the disease,” said Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases in Bethesda, Maryland. “It was a bit of a surprise to us.”

It’s the first time the prominence of obesity has been widely recognized among severely ill flu sufferers, Fauci said in a July 9 interview. “It’s very likely that if we went back retrospectively and looked at people who did poorly during seasonal flu, what would shake out is that obesity would be one of the risks,” he said.

CDC researchers noted the association among California H1N1 patients in a May 22 report. The agency is investigating whether overweight people need different flu vaccinations. Last year, 26.1 percent of adults in the U.S. were obese, up from 25.6 percent in 2007, the CDC said in a July 8 statement.

Severe Pneumonia

Some patients are showing up at hospitals with viral pneumonia so severe they are suffocating. All 10 of the Michigan patients, ages 21 to 53, suffered acute respiratory distress and weren’t getting enough oxygen even when put on a conventional mechanical ventilator.

The patients, who represent “the most severely ill subset” of H1N1 sufferers, were notable for several reasons, the CDC said. Nine were male, five developed dangerous clots in the lung and major organs became dysfunctional in nine of the patients. The body mass index of nine patients ranged from 34.2 to 58.9, according to the report. People with a BMI of 25 to 29.9 are considered “overweight” and those higher than 30 are “obese.”

“The high prevalence of obesity in this case series is striking,” CDC said.

A 5-foot, 5-inch (1.65 meters) woman is considered overweight at 150 pounds (68 kilograms) and obese at 180 pounds. A 6-foot man is considered overweight at 184 pounds and obese at 221 pounds.

Cause or Complication

Scientists don’t yet know whether extremely overweight people get sicker because of associated conditions like heart disease and asthma, or whether the excess fat itself makes them more vulnerable. Both may be to blame.

Fat cells secrete chemicals that cause chronic, low-level inflammation that can hamper the body’s immune response and narrow the airways, says Tim Armstrong, a doctor working in the WHO’s chronic diseases department in Geneva.

What’s more, excess fatty tissue compresses the chest, and the fatty infiltration of the chest wall causes a decrease in lung function and an increase in the pulmonary blood volume, Armstrong said. “If you are obese, you tend to be less physically active and have an associated shallower breathing pattern. All these compound, leading to breathing difficulties.”

Insulin Resistance

The morbidly obese also are more likely to experience insulin resistance, a condition that makes it harder for doctors to lower the level of sugar in the blood of critically ill patients, said Greet Van den Berghe, head of acute medical sciences at Belgium’s Catholic University of Leuven.

“The question has always been, is it the obesity or the other problems?” said Melinda Beck, professor of nutrition at the University of North Carolina, Chapel Hill. “There haven’t been studies that looked just at weight. In my research, it appears to be the obesity itself.”

In mouse studies, flu killed about half of the rodents made obese by a high-fat diet, compared with a mortality rate of about 4 percent in lean animals, according to Beck’s research. She is studying whether obese humans might need stronger doses of vaccine or a different method of delivery.

People may reduce their risk of developing complications from swine flu -- as well as many other diseases -- by maintaining a healthy weight, quitting smoking, exercising regularly and moderating alcohol intake, said Frederick Hayden, a clinical virologist at the University of Virginia.

Rates Jump

Obesity rates have tripled in the U.S., U.K. and Australia during the past three decades, according to the Organization for Economic Cooperation and Development. The ranks of the overweight are also swelling in the developing world. In China, obesity doubled among women and tripled in men between 1989 and 2000 and it may double again in 20 years, according to research released last year in the journal Health Affairs.

Studies are needed to better understand the immune response of obese people and determine whether excess body weight impairs their ability to fight the infection, said Pamela Fraker, a professor of biochemistry at Michigan State University.

“It’s sort of strange that it’s been neglected with this major population,” Fraker said. “We need to know about this for the further care and protection of the growing number of obese we have and for society in general.”