People with hyperhidrosis – an excessive sweating condition – also seem to have higher-than-average rates of anxiety and depression, a new study suggests.
Roughly 21 percent and 27 percent of people with hyperhidrosis screened positive for anxiety or depression, respectively. That compared with 7.5 percent and just under 10 percent of other patients, the study revealed.
The findings do not prove that hyperhidrosis caused those mental health issues. In some cases, excessive sweating may be part of an anxiety disorder, for example.
"It's not clear if this is cause-and-effect," said Dr Dee Glaser, a professor of dermatology at Saint Louis University School of Medicine.
Read: Reducing perspiration
So the findings don't necessarily imply that better control of hyperhidrosis would ease people's depression and anxiety, according to Glaser, who wasn't involved in the study.
"But," she said, "dermatologists should be aware of the higher prevalence of anxiety and depression in these patients."
And if necessary, Glaser added, they can refer patients to a mental health professional.
Avoiding social activities
Hyperhidrosis is a medical condition that causes people to sweat excessively and unpredictably – including when they're at rest or in cool conditions. It's estimated that about 3 percent of Americans have hyperhidrosis, according to the International Hyperhidrosis Society.
There are treatments, such as strong antiperspirants, Botox injections for underarm sweating, and electrical stimulation to dial down sweat-gland activity in the hands and feet.
Still, it's common for people with hyperhidrosis to feel self-conscious and avoid social activities – or even things as mundane as raising a hand in class, Glaser said.
"For people who don't have hyperhidrosis, it's easy to think, 'Oh, it's just sweating'," Glaser noted. "The impact it can have on quality of life has always been underestimated."
For the new study, Dr Youwen Zhou and colleagues wanted to get a clearer idea of whether overt depression and anxiety disorders are especially common among people with hyperhidrosis.
The researchers had just over 2,000 patients at two dermatology clinics – one in Canada and one in China – answer standard questionnaires that screen for depression and generalised anxiety disorder.
More research needed
It turned out that both conditions were more common among hyperhidrosis patients, and the risk was higher when their sweating problems were more severe, the findings showed.
"This study suggests that hyperhidrosis is tightly linked to depression and anxiety," said Zhou, who directs the Vancouver Hyperhidrosis Clinic at the University of British Columbia, in Vancouver, Canada.
But like Glaser, he said the findings do not necessarily mean that hyperhidrosis is the cause.
In fact, Zhou said, it may be "more likely" that some other underlying factors contribute to both hyperhidrosis and depression and anxiety. "More research is needed to uncover this mechanism," he said.
For now, both Zhou and Glaser suggested that hyperhidrosis patients talk to their doctors about any mental health symptoms.
"Don't feel like you have to just live with it," Glaser said.
The findings are published in the Journal of the American Academy of Dermatology.