MedWire News: Children with high levels of body fat at the age of 6 months face an increased risk of asthma-like symptoms at the age of 3 years, US researchers have found.

"Asthma, the most common cause of chronic childhood disease in the USA, is the paediatric diagnosis most frequently resulting in admission to hospitals1 C.T. Merrill and A. Elixhauser, Hospitalization in the United States, 2002: HCUP Fact Book no 6, Agency for Healthcare Research and Quality, Rockville (MD) (2005) Available at: http://www.ahrq.gov/data/hcup/factbk6/. and school absences," explain Dr Elsie Taveras, from Harvard Medical School in Boston, Massachusetts, and colleagues.

"Thus, it is important to investigate possible early-life risk factors for asthma incidence."

As previous studies have suggested that obesity is associated with an increased risk of asthma in adolescence and adulthood, the team studied whether high body fat levels in very early life are associated with an increased risk of asthma-like symptoms in early childhood.

The researchers studied data on the weight and length of 932 children at the age of 6 months. From this data, the researchers calculated each child's weight in relation to their length - an indicator of body fats levels at this young age.

The team then monitored the children until the age of 3 years and identified all those who were regularly wheezing.

Analysis revealed that children who were heavy for their length at the age of 6 months were significantly more likely to be wheezing at the age of 3 years than those who were normal or light for their length.

Indeed, each 1-unit increase in weight was associated with a 1.4-fold increased risk of recurrent wheezing and a 1.2-fold increased risk of any wheezing.

"Infants with higher weight-for-length scores at 6 months of age had a greater risk of recurrent wheezing by age 3 years," the researchers summarise in the Journal of Allergy and Clinical Immunology.

But they add: "It is unclear whether the relationship of infant adiposity [body fat] and early-life wheeze extends to allergic asthma or wheeze that can persist into later childhood."

Nevertheless, Dr Taveras and team conclude: "Our findings suggest that early interventions to prevent excess infant adiposity might help reduce children's risk of asthma-related symptoms."