Obesity, asthma, and misdiagnosis

January 01, 0001

Obesity, asthma, and misdiagnosis

With the growing obesity epidemic, the interactions between obesity and other diseases can increasingly become important. These Canadian researchers sought to compare patient characteristics and severity of disease between obese and normal weight people with asthma, and to examine reasons for misdiagnosis. Obese and normal weight patients with physician-diagnosed asthma involved in a larger study were selected. Asthma diagnosis was confirmed via a lung function testing algorithm. Logistic analysis was conducted to compare obese and normal-weight-confirmed people with asthma and to assess characteristics associated with misdiagnosis of asthma.

The researchers report: "Complete assessments were obtained on 496 subjects who reported physician-diagnosed asthma (242 obese and 254 normal- weight subjects). Three hundred forty six had asthma confirmed with sequential lung testing, and in 150 subjects a diagnosis of asthma was ruled out. Obese subjects with asthma were significantly more likely to be men, have a history of hypertension and gastroesophageal reflux disease, and have a lower FEV1 compared with normal-weight subjects with asthma. Older subjects, men, and subjects with higher FEV1 were more likely to have received misdiagnoses of asthma. Obesity was not an independent predictor of misdiagnosis, however there was an interaction between obesity and urgent visits for respiratory symptoms. The odds ratio for receiving a misdiagnosis of asthma for obese individuals as compared with normal-weight individuals was 4.08 for those with urgent visits in the past 12 months."

The authors concluded: "Obese people with asthma have lower lung function and more comorbidities compared with normal-weight people with asthma. Obese individuals who make urgent visits for respiratory symptoms are more likely to receive a misdiagnosis of asthma."

Obesity poses risks to lung function as well as misdiagnosis of asthma.

For the full abstract, click here.

Chest 137(6):1316-1323, June 2010 © 2010 American College of Chest Physicians
A Comparison of Obese and Nonobese People With Asthma. Smita Pakhale, Steve Doucette, Katherine Vandemheen, et al. Correspondence to Smita Pakhale: [email protected]

Category: R. Respiratory. Keywords: obesity, asthma, misdiagnosis, urgent visit, FEV1, case-control, journal watch.
Synopsis edited by Dr Paul Schaefer, Toledo, Ohio. Posted on Global Family Doctor 23 July 2010

Pearls are an independent product of the Cochrane primary care group and are meant for educational use and not to guide clinical care.