Men taking medication to reduce their prostate cancer symptoms are likely to develop type 2 diabetes, research suggests.
Patients with enlarged prostate who are prescribed drugs called 5-alpha reductase inhibitors have about a third of those at greater risk of the condition.
They reduce the production of androgens, a hormone that helps stimulate urine flow, a common problem in men with enlarged prostate.
But these drugs – including finasteride and dutasteride – can become slower metabolism and decrease the insulin sensitivity of the body, which can cause type 2 diabetes.
Finasteride made the headlines when Donald Trump & # 39; s physician Harold Bornstein revealed that the president is using the controversial drug to fight baldness.
Prostate patients who use a commonly prescribed medication to urinate run a third risk of type 2 diabetes, research suggests (stock)
The research was conducted by the University of Edinburgh and University College London. It was led by professor Ruth Andrew, a personal chairman of pharmaceutical endocrinology in Edinburgh.
& # 39; We discovered that many prescription drugs for prostate disease can increase the risk of type 2 diabetes, & # 39; said Professor Andrew.
More than three million finasteride recipes are published each year by the NHS in England – and many more are purchased privately.
In the US, about eight million a year take it for prostate issues and 1.2 million for hair loss.
The 5-alpha reductase inhibitors are often prescribed for the treatment of benign prostatic hyperplasia (BPH), the medical term for an enlarged prostate.
This is more common with age, with an estimated prevalence of between eight and 60 percent in men aged 90 years.
To determine the health effects of the drug, the researchers analyzed the medical records of 55,275 men in the UK who had been prescribed 5-alpha reductase inhibitors for their BPH for 11 years.
Results – published in the British Medical Journal – revealed that the drugs increase a man's risk of developing type 2 diabetes by about a third.
WHAT IS FINASTERIDE?
Finasteride was originally developed to treat urinary problems in men, but during tests, scientists found an unexpected side effect – hair growth.
In 1997, the FDA approved the steroid inhibitor as the first drug ever to treat male pattern baldness.
Once a day the drug is mainly sold under the brand name Propecia.
Millions of American adults use the pills, which are proven to be 90 percent effective.
It is not certain how many men in the UK use it because it is only available on prescription and is not available at the NHS.
But Asda can sell the drug without a prescription, because it will be available through pharmacotherapy-led group therapy.
This means that patients must be seen by a pharmacist before they receive the medicine.
One of the reported side effects that occur when taking the drug, which can often take months, is a loss of libido and erectile problems.
The drug has been increasingly monitored in recent years by regulators in the United States and Canada due to a possible connection with psychological problems.
And research of men older than 66 published in March provided the first concrete evidence of the risks for depression and self-harm.
Scientists at Western University found that men who used the drug, known as a 5ARI, had an 88 percent higher risk of injuring themselves. Their risk of depression was 94 percent higher.
The drug works by lowering the level of the hormone dihydrotestosterone, which can damage the hair follicles. This is also how it makes prostate glands smaller.
This means that in a group of 500 men taking the medication for 20 years, 16 cases of type 2 diabetes are likely to develop in people who would otherwise not have the condition.
A similar effect was seen when the team repeated the study with the medical records of 91,681 Taiwanese men.
& # 39; By studying real word data from different ethnic populations in the UK and Taiwan, we discovered that men being treated with dutasteride or finasteride for BPH have an approximately 30 percent increased risk of developing diabetes, & # 39; said Dr. Wei.
The findings suggest that men taking these drugs may require additional health checks to monitor warning signs of diabetes, such as unexplained weight loss, extreme thirst, and fatigue.
& # 39; These findings will be especially important for health screening in older men who already have a typical higher risk of type 2 diabetes & # 39 ;, said Professor Andrew.
If these symptoms occur, the man's prescriptions may need to be adjusted, the researchers claim.
However, they emphasize that patients taking these drugs should continue to do so as directed.
And they have added treatment guidelines that do not need to be changed based on their study.
Dr. Wei, however, added: "It is important that all patients are made aware of the risks and benefits of their medication.
& # 39; In this case, men should be warned of the increased risk of diabetes if they are taking these specific drugs for BPH and should contact their doctor if they are concerned. & # 39;
Professor Andrew claims that the researchers will continue to study patients taking these drugs to help them understand who is most at risk.
Laurence Stewart, a urologist at Spire Murrayfield Hospital and honorary consultant at NHS Lothian – who was not directly involved in the study – said: & These findings should not be a major concern for men taking 5-alpha reductase inhibitor drugs.
& # 39; As doctors, we may need to review the way we monitor our patients to ensure that we are extra alert to early signs of diabetes.
& # 39; Anyone who is worried should contact their doctor or urologist for advice on alternative treatments. & # 39;
Research suggests that finasteride triggers hair growth in up to 80 percent of men, but one in sixty years then experiences impotence – and the risks increase the longer they are on the drug.