Heat Waves Can Stir Up Tummy Troubles

Inflammatory bowel disease and infectious gastroenteritis both worsen during heat waves

(RxWiki News) Excessive heat can be both physically and emotionally draining. Besides being a nuisance, heat waves can also cause certain conditions to flare up.

A recent study reported an increased risk of inflammatory bowel disease flare-ups and infectious gastroenteritis in patients during heat wave periods.

According to this study, hospital admissions for these two conditions increased by 4 to 6 percent for each additional day within a heat wave period.

"Ask your doctor about the effects of heat waves on your health."

This study was conducted by Christine N. Manser, MD, at the Clinic of Gastroenterology and Hepatology at University Hospital in Zurich, Switzerland.

The aim of the study was to examine the impact of heat waves on the rates of infectious gastroenteritis and inflammatory bowel disease flares.

Infectious gastroenteritis is an inflammation of the gut caused by infection with bacteria or viruses.

Inflammatory bowel disease (IBD) is a condition in which the lining of the gut gets inflamed due to the person’s immune system attacking their own cells. Ulcerative colitis and Crohn’s disease are the two most common forms of IBD.

The main symptoms of both IBD and infectious gastroenteritis are diarrhea and abdominal pain.

A flare of IBD is when the usual symptoms associated with the condition suddenly get worse.

For this study, the researchers looked at data from 738 IBD patients and 786 infectious gastroenteritis patients over a five-year period (2001-2005). Data from other types of inflammations of the intestine were used as a comparison.

A total of 17 heat waves were identified between 2001 and 2005 by a Swiss weather agency. The researchers examined the occurrences of infectious gastroenteritis or IBD flare with a hospital admission.

The occurrence of a heat wave increased the risk of having an IBD flare by 4.6 percent and infectious gastroenteritis by 4.7 percent for each additional day of a heat wave. There was no significant difference in symptoms in the comparison group during the days with a heat wave.

Overall, the researchers found a substantial increase in hospital admissions because of flares of IBD and infectious gastroenteritis during heat wave periods.

The effect of a heat wave on infectious gastroenteritis was strongest but with a delay of 7 days. The effect of a heat wave on IBD flares was immediate, suggesting that the two conditions occurred due to heat waves, but by different mechanisms.

"While it can be difficult to predict the occurrence of flares when a person has IBD, this study provides information that may help with that. It may be possible to develop a routine to decrease your risk of flares during heat waves by working with your gastroenterologist and being aware of upcoming heat waves," Alexandra Reimann, ND, a primary care physician at Valhalla Wellness, told dailyRx News.

"All people should also be aware that heat waves can increase the risk of infectious gastroenteritis and take steps to lower their risk by carefully monitoring the food and drink that they and their families consume and encouraging frequent hand washing. While these tactics may not eliminate all flares or GI infections, this knowledge is another tool that patients and their doctors can utilize in their care," said Dr. Reimann. 

“Heat waves are known to cause physical stress as evident from increased frequencies of other stress dependent health events such as heart attacks. Physical as well as mental stress has been shown to cause flares of IBD, and may explain the increase in IBD hospital admissions during heat waves,” said Dr. Manser in a press statement.

“During a heat wave, patients with IBD should be aware that there is an increased risk for a flare and contact their gastroenterologist in cases of an increase of stool frequency or abdominal pain. The public should know that a sudden onset of abdominal pain and diarrhea during or shortly after a heat wave might be symptoms of an infectious gastroenteritis,” Dr. Manser noted.

The results of this study were published August 13 in The American Journal of Gastroenterology.

The study was funded by a research grant from the Swiss National Science Foundation.The authors disclosed no conflicts of interest.

Review Date: 
August 24, 2013