High BMI and COPD Outcomes in Alpha-1 Antitrypsin Deficiency

<h3>Background</h3> Elevations in BMI impact morbidity in patients with COPD in general, but little is known about its impact in patients with COPD due to alpha-1 antitrypsin deficiency (AATD-COPD). <h3>Research Question</h3> What is the prevalence and clinical impact of high BMI in AATD-COPD? <h3>Study Design and Methods</h3> A total of 646 patients completed clinical and health-related quality of life (HRQoL) questionnaires for 2 years. Patients were grouped by baseline BMI categories (underweight, normal, overweight, obese, and morbidly obese) to compare symptoms, exacerbations, HRQoL, and 5- and 10-year survival. Relation between changes in BMI over time on HRQoL was assessed. <h3>Results</h3> The cohort's mean age ± SD (55 ± 9.2 years), sex distribution (50.1% male), and mean % FEV₁ ± SD (36.6% ± 17.0%) was similar across all BMI categories. One-third (31.6%) had normal BMI, 5.6% were underweight, and 62% had a high BMI (37.3% overweight, 16.1% obese, and 9.4% morbidly obese). Patients with a high BMI had significantly worse St. George's Respiratory questionnaire (SGRQ) and 36-Item Short Form Survey (SF-36) physical composite scores than patients with normal weight. Patients with morbid obesity had the highest odds of being in the worst SGRQ (OR, 3.8; 95% CI, 1.9-7.8) and SF-36 physical composite (OR, 4.2; 95% CI, 2.1-8.1) quartiles and experienced more emergency department visits and hospitalizations than patients with normal weight (<i>P</i> < .05). Patients who transitioned to a higher BMI category over time reported worsening of SGRQ and SF-36 physical composite scores (<i>P</i> < .05) and vice versa. Despite their higher morbidity, no difference in survival was observed between patients with high BMI and normal BMI after a mean follow-up of 9 years. <h3>Interpretation</h3> BMI above normal is prevalent in patients with AATD-COPD and is associated with greater comorbidity and poor HRQoL but does not impact survival. HRQoL is inversely affected by BMI changes over time.