An article has been published in the current issue of the New England Journal of Medicine titled, Lung Function in Rescue Workers at the World Trade Center after 7 years. The first author is Thomas Aldrich and I did make contact with him this afternoon. (He responded to two of my emails in great detail and I appreciate his time.)
The article is available on line, in full (linked above). The researchers are from the Albert Einstein College of Medicine of Yeshiva University and Montefiore Medical Center,and worked in collaboration with FDNY and The Office of Health Services of NYC. The senior author is David Prezant.
The research goal was to evaluate the lung functioning of emergency response workers after the World Trade Center collapsed on September 11 2011. The study did include a great number of fire fighters and emergency medical service or EMS workers. The study included those individuals for whom prior medical or health records existed and who were employed and working at the disaster site between September 11 and September 24. The men and women were followed for six additional years. Over 12,000 persons were included.
The test for lung function involves a spirometer. The person blows into the device and a measure of Forced Expiratory Volume or FEV is determined. This is the same type of test given to determine a person's lung age. It has been used in previous research to show that smoker's lungs age at significantly faster rates than non smokers. Still everyone loses some amount of lung capacity or function as they age.
In this study, the scientists looked at normal FEV levels AND predicted FEV values - I am pretty certain that the predicted value is a measure of lung age based on normal situations. (If you ever had a bone mineral density test, think of the tscore and zscore - one compares you to a young person and the other compares you to people your same age).
Data existed on several variables, including FEV prior to September 11, height, weight, BMI, smoking status, sex, race, time arrived at crash site, duration of time spent at crash site. I have got to say that the sample was overwhelmingly male - but around 25% of EMS workers were female. The smoking status is somewhat skewed, which is something I asked Dr. Aldrich about in my email. It appeared at first as though thousands of workers quit smoking after the event - which would make sense in response to the amount of lung damage they experienced but then that would be offset by the amount of stress the workers experienced. Instead, the data indicates whether or not the respondents smoked at ANY time prior to 9/11 - not only if they were smokers ON 9/11. (The purpose for asking about forming smoking status would be that the lungs would already have some damage)
The results however, do note current smoking status, and of course, the decline in lung function is worse in smokers. The other variable factor that turned my head - BMIs. Remember the characterization of the workers is divided by time of arrival or time at site and then by fire fighter or EMS status. At each time period the BMI average was 28 to 30. In case you have forgotten, the normal weight BMI is 18.5 to 24.9. Yes, the BMI can be skewed by brawny men, and I imagine their would be some brawny firefighters, but some of this is overweight. Lung function is affected by weight as well.
So - back to the study. The responders, especially the firefighters, had significant decline in lung function over the first year after 9-11. In the past, workers exposed to such chemicals as found in smoke have also been tested and the loss of function in those cases appears to have reversed in a relatively short amount of time. In this situation, seven years after the fact, the 10% loss of lung function did not reverse.
In my speaking with Dr. Aldrich I noted that this reminded me of how a smoker can stop the accelerated lung decline through smoking cessation but cannot reverse it. (i.e I quit smoking at age 32ish - my lungs were probably ten years older than that - now I am 44 and they are probably 54 - but would have been much older had I kept smoking) He said that he had thought something similar. He said that the responders did in fact have symptoms similar to a person who had been smoking for 8 to 10 years. He described these symptoms as coughing, shortness of breath and lack of response to medications that help to relax bronchial tubes.
It is too soon to know if these brave persons will have higher cases of COPD or Lung Cancer, but from reading the information provided in this study, I expect that they will.
No comments:
Post a Comment