More than half of the adults hospitalized in the early days of the influenza A(H1N1) pandemic in New York City were obese, and 92% of the obese patients had underlying medical conditions, according a review published in the Centers for Disease Control and Prevention's Morbidity and Mortality Weekly Report.
To quickly assess the severity of illness and identify those at greatest risk from the emerging virus, researchers at the New York City Department of Health and Mental Hygiene reviewed data from the first 99 patients with polymerase chain reaction–confirmed H1N1 influenza admitted to any hospital in the city during April 25–May 24, 2009.
The study population of 54 men and 45 women was disproportionately young, compared with the general population, the researchers indicated (MMWR 2010;58:1436-40).
A total of 95 patients had fevers when they were admitted to the hospital, and 89 complained of cough. In addition, 37 children and 36 adults had at least one underlying medical condition known to increase the risk of complications from flu, and 7 children and 10 adults had more than one such condition.
Asthma, the most common underlying medical condition, was noted in 29 children (50%) and 19 adults (46%). Chronic metabolic disorders, including diabetes, were reported in 11 patients (11%).
Body mass index data were available for 28 children and 20 adults. Five children and 12 adults were obese (BMI between 30 and 40 kg/m
Three of the four patients who died were obese, and their underlying medical conditions included asthma and Down syndrome, according to the investigators.
A total of 76 patients (77%) were treated with oseltamivir, and 36 (47%) of these were treated within 2 days of the onset of symptoms, but the median time to treatment from the onset of illness was 3 days. Hospital stays were significantly shorter for patients who started antiviral therapy within 2 days, the researchers noted.
The study was limited by several factors including the potential underreporting of cases and the difference in reporting protocol later in the pandemic, when data were collected from sentinel hospitals only.
But H1N1 data collection from sentinel hospitals is underway, with an emphasis on gathering height and weight information to better determine the impact of obesity on hospitalization.
Meanwhile, “public education campaigns should encourage patients at high risk of severe illness to be vaccinated,” the researchers said.