Asthma in Healthcare

Many healthcare workers are at occupational risk for asthma, thanks to their exposure to cleaning and other products that are omnipresent in hospitals and other facilities. In 2003, researchers at the University of Texas Health Science Center (UTHealth), Houston, found an elevated prevalence of asthma among healthcare workers — notably 7.3 percent of nurses and 5.6 percent of respiratory therapists experienced onset after they entered the healthcare field.

Now, more than a decade since that study (published in 2007) was completed, a second examination of the issue began in September. Researchers, led by UTHealth principal investigators George Delclos, MD, PhD, and David G. Gimeno, PhD, are about to examine what has happened in terms of healthcare workers’ product exposures, tasks and procedures – and asthma prevalence — in the more informed intervening years. The work is being funded by a $1.3 million grant from the CDC and the National Institute for Occupational Safety and Health (NIOSH).

From AIDS to Asthma
Delclos told ADVANCE the original research finds historical roots in the 1980s’ AIDS epidemic and the eventual understanding that healthcare workers could contract HIV from a needlestick. “There was heightened awareness given to healthcare workers as a group at risk for developing injuries and illnesses as a consequence of their job,” said Delclos. The AIDS experience led to 1992 passage of the OSHA blood-borne pathogen standard which led, in turn, to the concept of standard precautions and greater use of PPE. “This brought about a huge increase in the use of latex gloves, both powdered and non-powdered, as well as on cleaning and disinfection practices,” explained Delclos. “Then we began to see isolated case reports of healthcare workers developing asthma, thought to be a consequence of their exposure to powdered latex gloves. At the same time there were other reports coming out on healthcare workers having asthma after being exposed to glutaraldehyde, a sterilizing agent used to sterilize medical endoscopes.”

The FDA came out with an alert to minimize use of latex, but Delclos said what was still lacking was a population-based study of healthcare workers that could measure just how prevalent asthma was among certain worker groups, and if high, what some of the associated risk factors might be. This led to the 2003 study.

The earlier study targeted four groups: nurses, RTs, physicians and occupational therapists. “We targeted RTs because there had been some isolated reports of asthma, and other respiratory symptoms, developing among RTS who had been administering certain aerosolized medicines. Again, this tied into the AIDS epidemic because one of the things being administered in the late 80s and early 90s was aerosolized pentamidine for the prevention of Pneumocystis pneumonia in AIDS patients. Aerosolized pentamidine can be a respiratory irritant, causing people to cough – including the RT standing next to the patient. That gave rise to the design of isolation booths from which to administer the meds.”

Asthma in HealthcareWho Is at Risk?
The findings from that first study were revealing: asthma onset following entrance into the healthcare field was highest among nurses (7.3%), followed by RTs (5.6%). Prevalence was not as high among doctors or OTs. “We looked closely at a variety of exposures, practices and tasks at work and found interesting associations. Exposure to medical disinfectants and cleaning products — and remember RTs assist with bronchoscopies and are often asked to clean the bronchoscopes — was a clear risk factor,” said Delclos. “Another was exposure to cleaning in general — of surfaces and patient rooms. And while RTs don’t clean rooms, they are around it all day because a hospital environment is cleaned constantly. We also found the administration of aerosolized medicines to be a risk factor for new onset asthma.”

Delclos said the new study will hone in on determining whether the prevalence rate of asthma among healthcare workers has changed, given the wider recognition of the problem, newer products and updated procedures.

“Cleaning practices have changed in 10 years. For example, there is a greater push to introduce green chemicals,” said Delclos.”That may be great for the environment, but we still do not know much about their effect on human health. We don’t know that green always equals healthy.”

Delclos also noted that the use of bleach in healthcare settings, definitely associated with asthma in the U.S. and in Europe, had initially gone down. But now, with growing concern of antibiotic resistant organisms in hospitals — especially c. difficile which is very susceptible to bleach — its use has gone back up again.

And while disinfectants of instruments tend to be automated and done in closed systems now (i.e. workers may not be as exposed), glutaraldehyde and similar cold sterilizing chemicals are still used. “For example, I have a patient who was around a closed system and it malfunctioned, leaking glutaraldehyde — and ultimately developed asthma. So there are still opportunities for exposure,” noted Delclos.

Have Changes Impacted Prevalence?
He explained that with the undertaking of new research, “We also want to see if the changes in practices and tasks have had any effect on the prevalence of asthma. For example, aerosolized medications: RTs administer nebulized meds the same way but there are certainly newer types of medications that are being aerosolized. Back when we did the original study it was primarily pentamidine, ribavirin, bronchodilators — now RTs are administering more antibiotics, gene therapies, and steroids. We’re interested if that has had any impact.”

Delclos said the new four-year study will take researchers into facilities to search through cabinets and identify products in use. They will also meet with targeted focus groups of healthcare workers to find out what has changed over the past decade, and who does what, when, how often, and with which products, instruments, medications, etc. This information will later be used to better identify exposures. In total 7,000 healthcare workers will be surveyed via questionnaires.

A new feature in the upcoming study will beto take a look at possible socioeconomic consequences from the high rate of asthma among healthcare workers. “Maybe that will translate to higher rates of absenteeism — or presenteeism since healthcare workers are often gung-ho and reluctant to take time off. A workplace with asthma flare-ups will have a ‘cost’ — to individuals, their health, their families . and maybe their work productivity.” And ultimately, that could be a cost to topnotch patient care.

Valerie Newitt is on staff at ADVANCE. Contact:

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