From the moment we are born, the colonization of our intestines by a variety of bacteria begins. Evidence suggests that different intestinal bacteria may differently affect the growth of the host.
Currently, 1 in 3 children and adolescents in the US are either overweight or obese. What is more, this obesity is not simply a consequence of unhealthy behaviors in adolescence - by the age of 24 months, 10% of children are obese.
Factors identified as influencing early childhood obesity include maternal pre-pregnancy body mass index (BMI), nutritional intake, physical activity, sleep duration and screen time. However, researchers have now begun to investigate the influence that colonies of microbes residing in the gut might have on early childhood obesity.
From the moment we are born, the colonization of our intestines by a variety of bacteria begins. Recent evidence has suggested that different intestinal bacteria may differently affect the growth of the host.
Some studies have also shown that antibiotic exposure can influence the diversity and composition of the gut-dwelling microbes. Therefore, the researchers behind the new study - from the Children's Hospital of Philadelphia, PA - wanted to investigate what influence antibiotic use might have on early childhood obesity.
Children prescribed antibiotics on four or more occasions by 24 months are 'at risk'
The study authors examined electronic health records from a network of primary care clinics, spanning the period 2001-13. In total, the analysis included 64,580 children who had annual visits at a clinic at the ages of 0-23 months, as well as one or more visits at ages 24-58 months. The study followed the children up until the age of 5 years old.
Of these children, 69% had received antibiotics before the age of 24 months, with an average of 2.3 antibiotic episodes per child. The authors found that there was an increased risk of childhood obesity among those who were exposed to antibiotics, particularly among children who had been prescribed antibiotics on four or more separate occasions.
However, the researchers report no association between obesity and narrow-spectrum antibiotics, which are prescribed to kill only a narrow range of bacteria. The obesity risk was associated only with broad-spectrum antibiotics, which are used to treat a wide range of bacteria.
The study also reports the prevalence of overweight/obesity in the children across the study period:
- At 2 years of age, 10% of the children were obese and 23% were overweight
- At 3 years - 14% obesity, 30% overweight
- At 4 years - 15% obesity, 33% overweight.
Of the study's findings, the authors write:
"Because obesity is a multifactorial condition, reducing prevalence depends on identifying and managing multiple risk factors whose individual effects may be small but modifiable. Our results suggest that the use of broad-spectrum outpatient antibiotics before age 24 months may be one such factor. This provides additional support for the adoption of treatment guidelines for common pediatric conditions that emphasize limiting antibiotic use to cases where efficacy is well demonstrated and preferring narrow-spectrum drugs in the absence of specific indications for broader coverage."
Last week, MNT reported on a study published in the BMJ that found 1 in 10 of all antibiotic prescriptions fail to treat infection. The authors of that study demonstrated that the failure rates for antibiotics rose over the past 2 decades, and they say that the rates will continue to rise.