Obesity’s many risks may include worsening asthma in children

20 Oct 2017 --- Obesity has been found to be a risk factor for repeated hospital admissions among children in Japan hospitalized for asthma, researchers report in a Pediatric Allergy & Immunology study. Asthma and obesity are common chronic illnesses and public health problems for children in developed countries like Japan. The prevalence of asthma and obesity is increasing, and the study authors note that several studies reported an association between obesity and asthma in children.

Obese group more likely to be readmitted
The study authors obtained the hospital discharge records of inpatients aged 3 to 8 years with a diagnosis of asthma using a national inpatient database in Japan. The researchers excluded children with chronic medical conditions other than asthma and obesity (congenital heart, kidney, pulmonary, endocrine, hematologic, gastrointestinal, and neurologic diseases; cancer or leukemia; and autoimmune disease) using version 2 of the pediatric complex chronic conditions classification system.

The study included 38,679 patients, including 3,177 underweight, 28,904 normal weight, 3,334 overweight and 3,264 obese patients. Those in the obese group were more likely to be readmitted to the hospital within 30 days of discharge and to have longer hospital stays than those in the normal-weight group. No significant difference was observed between the four groups regarding the need for intensive care and total hospitalization costs.

The study authors point out that obesity is an economically complicating factor for children hospitalized with asthma in the US. Nationwide studies in the US from 2000 to 2012 revealed that obesity was associated with increased hospitalization costs and prolonged length of stay among children with asthma. The differences in cost and length of hospital stay between normal weight and obese pediatric inpatients with asthma were US$1,588 to US$2,145 and 0.24 to 0.59 days, respectively.

In contrast, the results of the Pediatric Allergy & Immunology study demonstrated the difference in total costs between obesity and normal weight asthma patients was insignificant, which may have reflected the different payment and insurance systems between the US and Japan.

Furthermore, the study showed that the difference in length of hospital stay was 0.12 days between the two groups. “These differences in length of hospital stay may reflect the difficulty and complexity of procedures such as airway management, complications and greater severity of the illness,” the researchers note.

Limited but important
The researchers admit there were several limitations in the study. The number of preexisting allergic disorders may have been underestimated and led to the bias toward the null because of possible misclassifications. Several potential confounders could not be adjusted because detailed clinical information, patient socioeconomic factors, and laboratory data were unavailable in the Diagnosis Procedure Combination database, they add.

However, it is noted that a unique feature and strength of the study was the use of a national inpatient database to examine the associations between body mass index (BMI) and the clinical outcomes of asthma among hospitalized children in Japan. Using the Japanese database, researchers were able to calculate robust national estimates of the effects of obesity on asthma exacerbations among pediatric inpatients.

“Pediatric obesity was significantly associated with an increased risk of 30-day re-admission for Japanese children hospitalized with acute asthma exacerbation,” conclude the authors of the study. “Our investigations provide important information for the prevention of obesity in children with asthma.”

In other recent news, preventing asthma attacks may also be accomplished with vitamin D, according to another recent study showing nutrition’s effects on the condition. The research led by Queen Mary University of London (QMUL) found that taking oral vitamin D supplements in addition to standard asthma medication could halve the risk of asthma attacks that require a visit to the hospital.