Wednesday, February 27, 2013

COPD as a Syndrome


Typically, in medical journals, we don’t like to include a lot of formula or mathematical expressions in articles. However I recently read a paper where a mathematical expression is used to describe the COPD as a syndrome. It is a good use of mathematical expression in this case.


John J. Reilly “COPD and declining FEV1 – time to divide and conquer?” (NEJM 359:15: 1616-1618 OCT 2009)

“In fact, COPD in the singular is probably a misnomer. It is more appropriate to view COPD as a syndrome that encompasses a variety of obstructive diseases that share a common exposure but differ in terms of mechanism of disease and response to therapy. This concept is expressed in the mathematical notation


 
In which COPDn represents subgroups of COPD. As a reflection of this recognized heterogeneity, investigator have developed new classification systems, such as the BODE index, which evaluates the body-mass index, the degree of airflow obstruction and dyspnea, and exercise capacity to create a 10-point scale in which higher scores indicate a higher risk of death. In addition, investigators have attempted to define other homogeneous subgroups of patients with COPD. “

For many complicated diseases, when we have a better understanding about the disease, we will see that one specific disease may have many different manifestations or phenotypes – so called ‘heterogeneity’. When designing a clinical trial for a disease with heterogeneity, it may be difficult to show the treatment effect on the patient population as a whole. The drug may only be effective on one of many specific sub-populations. The difficult is usually in finding this specific sub-population. The newly issued FDA guidance “Enrichment Strategies for Clinical Trials to Support Approval of Human Drugs and
Biological Products” is attempting to address this issue. 

1 comment:

Nicole.lascurain@healthline.com said...

Hi Dr. Deng,

First off, I came across your site and wanted to say thanks for providing a great, much-needed lung health resource to the community.

Our readers have found this topic center to answer all of their COPD-related questions extremely useful, such as photos of what the disease can do to your lungs. I thought you might get a kick out of it as well: http://www.healthline.com/health/copd

Naturally, I’d be delighted if you share this resource on http://onbiostatistics.blogspot.com/2013/02/copd-as-syndrome.html , and/or share it with your followers on social. Either way, keep up the great work Dr. Deng!

All the best,

Nicole Lascurain | Assistant Marketing Manager
p: 415-281-3100 | e: nicole.lascurain@healthline.com

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