Swine Flu Packs Bigger Jolt For Obese as Striking Link Discovered
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 hasnt 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 its 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. “Its a huge problem.”
Seeking More Answers
So far, the evidence is anecdotal. No global or national data have been reported and the CDC said its 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 WHOs 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.”
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 werent 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