This article is more than 5 years old. Information may no longer be current.
Obesity related to influenza-associated respiratory mortality
Click Here to Manage Email Alerts
Obesity appeared to aggravate the effect of seasonal influenza on respiratory mortality, researchers from the University of Hong Kong reported.
“Obesity is a worldwide public health issue associated with chronic diseases,” the researchers wrote in Clinical Infectious Diseases. “The burden of influenza mortality attributable to obesity may be even larger in other countries with a higher prevalence of obesity than Hong Kong. Based on evidence of a relation between obesity and 2009 pandemic influenza, influenza vaccine priority has to be given to people with severe obesity (BMI ≥ 30) in many places including Hong Kong.”
The researchers, from the School of Public Health, Li Ka Shing Faculty of Medicine, used data from a prospective, population-based cohort of Chinese people aged 65 and older who were followed until death or May 2012. They estimated the effect influenza had on respiratory mortality rates, and then whether this association varied according to obesity.
Among the 65,841 participants included in the analysis, 29% died by the end of the study period, including 6% from respiratory complications. Respiratory mortality was higher during influenza season (HR = 1.13; 95% CI, 1.02-1.25). Before the 2009 influenza pandemic, associations between seasonal influenza and respiratory mortality were higher among obese individuals (HR = 1.19; 95% CI, 1.01-1.42), according to a multivariable analysis. During the study period, including the pandemic, the association was greater for obese individuals (HR = 1.11; 95% CI, 1.01-1.22).
In a subgroup of healthier individuals, the association between influenza and respiratory mortality persisted among obese individuals and was greater compared with normal weight individuals (HR = 1.35; 95% CI, 0.97-1.87).
“Appropriate protection against influenza should be considered for obese people with BMI [25 or higher],” the researchers wrote. “However obesity-related immune dysfunction causes decreased response to influenza vaccine in obese people. On the other hand, effective public health interventions including changes in diet and physical activity to reduce the increasing prevalence of obesity all over the world would provide the potential health benefits to reduce disease burden of both seasonal and pandemic influenza.”
Disclosure: One researcher reports receiving research funding from MedImmune and Sanofi Pasteur, and consulting for Crucell NV.
Click Here to Manage Email Alerts