Roddy Stinson
Web Posted: 09/13/2005 12:00 AM CDT
San Antonio Express-News

The so-called "Kelly cluster" of victims of amyotrophic lateral sclerosis (Lou Gehrig's disease) is a little more in focus today, thanks to the findings of an Air Force investigation.

The findings — contained in a 144-page report, "Case Series Investigation of ALS Among Former Kelly Air Force Base Workers" — were released to the Express-News last week.

In sum, the researchers concluded:

"... The lack of salient predictors for ALS, combined with the varied Kelly ties among the participants and the observational nature of our study (i.e., no comparison group), makes it difficult to hypothesize what kinds of detrimental exposures, if any, might have been common to the cases."

In the process of coming to that non-conclusion, the Air Force scientists uncovered considerable intriguing information.

That will surprise no one who has followed this fascinating story since the cluster was first mentioned in a Dec. 20, 1998, Express-News article about a San Antonio woman's battle with ALS.

In that piece, a University Hospital neurologist noted that about 10 ALS patients in the hospital's Reeves Rehabilitation Center were former Kelly AFB workers.

From that hint of a health problem just begging to be investigated grew an October 2000 Express-News report, "Connection or Coincidence: High numbers of ALS disease seen in Kelly workers."

Subsequently, the Air Force Institute for Operational Health launched an extensive years-long effort to (1) identify ALS victims with links to Kelly and (2) analyze data collected from those victims and their families.

Ultimately, 95 questionnaires were completed by ALS victims or their loved ones, and 93 were included in the institute's analysis.

The questionnaire elicited information about sex, age, ethnicity, medical history, recreational activities, tobacco/alcohol use, military service and work history, including exposure to chemicals and metals.

Space limitation prevents me from discussing all of the statistics in those areas, but several findings stand out:

The overwhelming majority of participants (83 percent) "identified themselves as White/Caucasian, and only 13 percent self-identified as Hispanic/Latino. This finding is different from the prevailing demographic pattern in Bexar County."

"Over 90 percent of the 93 participants were male, which constituted a major difference between our cases and those described in (other ALS-research) literature. ... At 10.6 males per female, the gender ratio was roughly 5 to 6 times greater than what is normally reported."

"Another noteworthy and rather unexpected finding was that 6.5 percent had been professional or semi-professional athletes. ...

"This reported athleticism, coupled with a low prevalence of obesity-related diseases, suggests that our cases were generally more active than U.S. males of similar ages."

"Among workers who reported working at Kelly in the 20 years prior to diagnosis, the most frequently contacted substance was jet fuel fumes (30 percent), followed by cleaning solvents/degreasers (28 percent) and aluminum (25 percent)."

"A large percentage (80 percent) reported having a military service history. ...

"Interestingly, a recent report found that U.S. males with any military service history prior to the Gulf War are 60 percent more likely to develop ALS than U.S. males without a military service history.

"The apparent preponderance of veterans in our (Kelly AFB) series might somehow be associated with this phenomenon; however, there is no way to tell from our study.

"In any case, more years of data will be required to determine if there is increased incidence of ALS among U.S. vets, and if so, what might have triggered these increases."