A new study presented at ATS 2018 found that COPD patients who are extremely overweight (BMI > 40) do not have the same “obesity paradox” advantage in terms of both mortality and morbidity as compared to mildly obese patients.
The study found that underweight patients (BMI < 20) had a higher mortality rate compared with those of normal weight (BMI 20-25). Those with with BMI > 40 also had a mortality disadvantage.
Compared with in the normal weight group, mortality was lower in the overweight group (BMI 25 to 30) and the two obese groups (BMI 30-35; and BMI 35-40).
Why might the obesity paradox fade out at higher BMIs?
“Higher BMI is associated with a higher prevalence of a number of diseases that contribute to mortality, including metabolic and cardiovascular diseases,” study author Emily Brigham, MD, MHS, of Johns Hopkins University School of Medicine in Baltimore, told MedPage Today. “It is reasonable to expect that at some threshold the positive effects of BMI in this population will be overwhelmed by the negative health consequences of obesity, as we see here.”