Research in the Extreme

From the heat that firefighters face to the intense pressure under which many divers operate, the research he directs at the Center for Research and Education in Special Environments (CRESE) has always aimed to understand how people can stay safe and productive even in extreme surroundings.

Some of Hostler’s most recent projects focus on the world of submariners, SEALs and divers—in other words, the United States Navy

What happens if sailors in a disabled submarine—who may be hot, dehydrated and breathing too much carbon dioxide–need to be rescued? Can they assist in their own rescue? The Navy has developed a tablet-based application to test an individual’s cognition to help answer these questions. Hostler and his colleague, Hayden Hess, PhD, will test the subjects’ reactions in the center’s hyperbaric chamber when they are hydrated and dehydrated to find out how those conditions affect the ability to think and react. The results of the study will help the Navy understand when planning a rescue.

Detecting air bubbles in the bloodstream of divers gives a good indication of suffering decompression sickness, also known as the bends, when they rise to the surface. The current method of testing for bubbles—ultrasound—is only available after surfacing. CRESE is testing a device developed by Creare that measures bubbles in real time while divers are still submerged, which could make for much safer decompression and rising. The hyperbaric chamber is again the setting to create air bubbles in test subjects and test how well the new device works versus ultrasound.

Another project for which Hostler is principal investigator looks at divers’ body temperature and heat tolerance when operating in warm water environments while wearing a drysuit. Thermal strain ultimately affects the divers’ ability to handle tasks effectively. Fully encased dive suits and completely sealed helmets allow divers to work—perhaps clearing a ship for mines or repairing a broken propeller—in warm contaminated water. But does that equipment really make divers’ lives safer when they’re already in a hot environment with no way to regulate their body temperature? This study will shed light on the ramifications of such scenarios.

Hostler is not alone in the special environment realm. Hess also has a strong interest in diving research. The other principal CRESE investigators, Riana Pryor, PhD, and Luke Pryor, PhD, work primarily on research in hot environments.

How much physical activity is truly beneficial for people over 60? A new study led by Michael J. LaMonte, PhD, research professor of epidemiology and environmental health, provides an answer. Published in JAMA Cardiology, the study of nearly 6,000 U.S. women aged 63-99 reports that, on average, 3,600 steps per day at a normal pace was associated with a 26% lower risk of developing heart failure. The observational study from the Women’s Health Initiative looked at accelerometer-measured physical activity, sedentary time and heart failure risk.

“In ambulatory older women, higher amounts of usual daily light and moderate intensity activities were associated with lower risk of developing heart failure with preserved ejection fraction independent of demographic and clinical factors associated with heart failure risk,” said LaMonte.

The New England Journal of Medicine was the outlet for an International Agency for Research on Cancer (IARC) special report on alcohol use and cancer risk. SPHHP’s Jo Freudenheim, PhD, SUNY Distinguished Professor of Epidemiology and Environmental Health, was a member of the working group that authored the report, “The IARC Perspective on Alcohol Reduction or Cessation and Cancer Risk.” The report’s first author is past Richard V. Lee Lecturer Susan Gapstur, PhD, of the IARC. Significantly, the authors agreed that, based on the epidemiological evidence (particularly large studies of long-term alcohol cessation) stopping drinking can lower the risk of getting cancers caused by alcohol. The working group specifically noted that reducing or eliminating alcohol use decreased the risk of oral and esophageal cancers.

SPHHP Dean Jean Wactawski-Wende, PhD, was a contributing author of a recent article in the Journal of the American Medical Association (JAMA) about the groundbreaking Women’s Health Initiative (WHI) hormone trials. The article aims to help clinicians interpret WHI findings that sought to determine the long-term risks and benefits of hormone therapy after menopause, focusing on chronic disease rather than menopausal symptoms. The estrogen-plus-progestin trial was halted in 2002 due to safety concerns, showing increased risks of breast cancer, heart disease, stroke and blood clots. The estrogen-only trial indicated increased risks of stroke and blood clots but lower breast cancer risk. The JAMA paper suggests that for menopausal women under 60, estrogen-alone therapy's benefits likely outweigh the risks. For estrogen-plus-progestin, the risk remains but is small in women under 60. Wactawski-Wende emphasized the importance of clinician consultation and using the smallest effective dose for the shortest time