Respiratory Illness And Death In COPD can Predicts by CT Scan

Respiratory Illness; CT scans of the lungs of smokers with chronic obstructive pulmonary disease when analyzed by a mathematical function called airway fractal dimension can estimate increased risk of death for a group of people who are not otherwise identified as high-risk by conventional tests.

That is a major finding of clinical importance in a Journal of Clinical Investigation study led by senior author Surya Bhatt, M.D., and first author Sandeep Bodduluri, Ph.D. “They show that a significant number of smokers; so without airflow obstruction who would be considered; so to have mild or no disease by traditional classification schema can be; identify to have high mortality risk base on grouping using fractal dimensions and peribronchial emphysema,” Bhatt said.

Analysis of CT scan

Bhatt is associate professor and Bodduluri an instructor in the Division of Pulmonary, Allergy and Critical Care Medicine in the University of Alabama at Birmingham Department of Medicine. A fractal is a pattern that repeats at successively smaller scales. Trees are an example limbs separate to large branches, then progressively through thinner branches and finally twigs, all in repeating patterns.

Lungs also develop in a fractal pattern with successively smaller scales; so that is specific to each individual. Large bronchi split to progressively thinner bronchi that end in 300 million tiny air sacs called alveoli, and altogether; so the alveoli in an adult lung have nearly the surface area of a tennis court. Bhatt and colleagues found that fractal analysis of COPD lungs delivers additional information that can tell a patient’s risk of greater illness or death.

COPD, which is cause primarily by smoking, is characterize by airway remodeling including narrowing of bronchial lumens and loss of branches. Current analysis of CT scans does detect these changes individually at each branching generation; but this new study by Bhatt and colleagues shows that calculation of airway fractal dimension, or AFD, can be use to quantify this loss of airway branching complexity.

Lung function decline

In a cohort of more than 8,000 smokers; so the researchers demonstrate that AFD was significantly; so associate with airflow obstruction and respiratory morbidity, as well as with lung function decline; hence after adjustment for traditional measures of airway narrowing. Specifically, they found that AFD was significantly associate with force expiratory volume in one second, or FEV1, after adjusting for variables that include age, race, sex, smoking status and pack-years of smoking.

Bhatt and colleagues also find that AFD was associate with respiratory quality of life; hence as report through a standard questionnaire; so with how far a patient with COPD can walk in six minutes. That six-minute distance decreases with worsening disease; the most severely ill COPD patients may achieve as little as 150 feet in six minutes of walking.

The researchers also found that AFD was associate with COPD exacerbations; lung function decline and mortality, as seen in follow-ups with a median duration of more than six years. COPD is a disease of airflow obstruction that steadily worsens over time; hence making it more and more difficult to breathe. Millions of people in the United States have the disease, and about 150,000 die each year.