Talking on mobile for just 30 mins a week can raise high blood pressure risk

By Mark Waghorn via SWNS

Chatting on your cell phone for just 30 minutes a week raises the risk of high blood pressure, a major cause of heart attacks and strokes, according to new research.

Those who spent that time talking, even hands-free, were 12 percent more prone to hypertension.

And just six hours a week raised the risk to 25 percent.

It could be fuelling rising cases of the deadly disease. Rates have more than doubled in recent decades.

Lead author Professor Xianhui Qin, of Southern Medical University, Guangzhou, said: "It’s the number of minutes people spend talking on a mobile that matters for heart health, with more minutes meaning greater risk."

"Years of use or employing a hands-free set-up had no influence on the likelihood of developing high blood pressure."

The Chinese team analyzed 212,000 people over 30 from the UK Biobank - a database containing genetic and other health information on around half a million Britons.

Participants who spoke on cellphones for 30 minutes or more per week had a 12 percent increased risk compared to peers who used them less regularly.

They were tracked for an average of 12 years.

Looking at the results in more detail, weekly usage time of 30-59 minutes, 1-3 hours, 4-6 hours and more than 6 six hours was associated with an eight, 13, 16 and 25 percent raised risk.

This was compared to participants who spent less than five minutes per week making or receiving calls.

What is more, the likelihood of developing high blood pressure rose by a third (33 percent) in those with a high genetic risk who spent at least 30 minutes a week talking on a mobile.

Overall, mobile phone users had a seven percent higher risk than non-users.

It is believed electromagnetic fields emitted by phones are behind the phenomenon. They have also been linked to brain tumors.

Prof Qin said: "Our findings suggest that talking on a mobile may not affect the risk of developing high blood pressure as long as weekly call time is kept below half an hour."

Almost three-quarters of the global population aged 10 and over own a mobile phone. Nearly 1.3 billion adults aged 30 to 79 have high blood pressure - compared to less than 600 million in the 1970s.

Mobile phones emit low levels of radiofrequency energy, which has been linked with rises in blood pressure after short-term exposure, said Prof Qin.

Results of previous studies on mobile phone use and blood pressure were inconsistent - perhaps because they included calls, texts and gaming.

Prof Qin and colleagues examined the relationship among a cohort who were free of hypertension at the outset.

Information on the use of a mobile phone to make and receive calls was collected through a self-reported touchscreen questionnaire including years of use, hours per week and using a hands-free device/speakerphone.

Participants who used a mobile phone at least once a week to make or receive calls were defined as mobile phone users.

The researchers also took into account an individual's age, sex, BMI (body mass index), race, deprivation, family history of hypertension, education, smoking status, blood pressure, blood fats, inflammation, blood glucose, kidney function and use of medications to lower cholesterol or blood glucose levels.

The average age of participants was 54 years, 62 percent were women and 88 percent were mobile phone users.

Added Prof Qin said: "More research is required to replicate the results, but until then it seems prudent to keep mobile phone calls to a minimum to preserve heart health.”

Over a quarter of adults in the UK, around 14.4 million have hypertension. More than five million have not been diagnosed. Dubbed the 'silent killer', there are no symptoms.

The findings are in European Heart Journal – Digital Health, published by the European Society of Cardiology.