Tadalafil, an erectile dysfunction drug, draws growing interest as a potential longevity and cardiovascular therapy
核心洞察
Tadalafil (Cialis), a PDE-5 (搜索) inhibitor used for erectile dysfunction (搜索), is increasingly promoted in wellness circles as a longevity drug with cardiovascular, cognitive, and performance benefits.
Observational studies show sizable associations: a 55% lower rate of cardiovascular death and 44% lower overall mortality among over 8,000 men, plus a 32% lower dementia (搜索) risk in a study of over half a million patients.
Experts caution that these retrospective findings show association, not causation, and emphasize the need for randomized controlled trials before routine clinical use.
Tadalafil — better known by its brand name Cialis — is one of the most commonly prescribed drugs for erectile dysfunction (搜索), but in biohacking and wellness circles it is increasingly being repurposed for an entirely different reason: as an all-purpose longevity drug. Online clinics and influential figures are promoting it as delivering benefits for the cardiovascular system, brain, and even athletic performance. The drugs are not approved for preventing heart attack and stroke, let alone for extending life, yet the enthusiasm reflects growing interest among some experts in cardiology and men's health that tadalafil and other drugs in its class could have a legitimate role in preventive health.
"It's a serious area of discussion," says Dr. Robert Kloner, chief science officer at the Huntington Medical Research Institute (搜索) and a professor at the University of Southern California. "Cardiovascular disease (搜索) remains the number one killer – and we have these drugs that may have a potential benefit, but we have to learn a lot more."
Mechanism and approved indications
Tadalafil belongs to the same class of drugs as sildenafil (Viagra), with the primary difference being that its effect lasts considerably longer. While mostly used for erectile dysfunction (搜索), both tadalafil and sildenafil are also approved for treating a rare form of high blood pressure affecting the lungs, as well as symptoms of an enlarged prostate in men. These medications, known as PDE-5 (搜索) inhibitors, work by preventing the breakdown of a signaling molecule, which in turn helps relax smooth muscle cells and dilate blood vessels. This not only improves blood flow in one particular region but also relaxes and widens blood vessels throughout the body, according to Kloner.
Sildenafil — approved in the late '90s — was famously developed as a drug to treat chest pain caused by poor blood flow to the heart, until its "side effects" were recognized and drug makers changed course. There is evidence, mostly from small trials in humans, that PDE-5 (搜索) inhibitors like tadalafil may benefit blood vessels, and lab and animal research has suggested these drugs can also have anti-inflammatory effects.
Observational findings
The major studies in this area are observational and retrospective, meaning they can only show associations, not that tadalafil was the definitive cause. Still, the findings are remarkably "consistent" across the literature, says Kloner, whose lab has studied these medications extensively. "It's a very interesting signal."
An analysis by Kloner of more than 8,000 men taking tadalafil found they had a 55% lower rate of dying from cardiovascular causes and a 44% lower rate of overall mortality during the study period. Another study, based on more than half a million patients, showed a 32% lower risk of dementia (搜索) among those taking tadalafil, along with improved mortality.
"We were particularly fascinated by the dementia (搜索) piece," says Dr. Dietrich Jehle, chair of emergency medicine at UTMB and lead author of the analysis, noting that data from the U.K. has also indicated a lower risk of Alzheimer's disease (搜索).
Researchers like Kloner and Jehle emphasize that without prospective studies — ideally randomized trials — these findings need to be read with caution. There could be unknown factors that influence why men who seek out medications for erectile dysfunction (搜索) are less likely to die and develop certain diseases. Kloner also acknowledges the drugs are not as well studied in women. The problem, he says, is that pharmaceutical companies aren't incentivized to run these costly studies because generic versions of the drugs are already available.
"It's not something that cardiologists are routinely recommending, I'll tell you that," Kloner says. "But these drugs in general are very safe."
The online marketplace and expert caution
Much of the current marketing around tadalafil comes from direct-to-consumer online clinics, where it is often advertised alongside other trendy wellness and longevity therapies. For example, AgelessRx (搜索) sells a monthly $70 prescription of low-dose tadalafil for longevity purposes. The company's medical director, Dr. Jenell Decker, told NPR she felt the data were strong enough to warrant offering it to both men and women over 40.
"In longevity, that's what you have to do with a lot of things, you have to infer," she says, "because if you wait until a person is already showing symptoms, you're already behind."
But some experts are troubled by this off-label use of the medication without better data in humans. "Absence of evidence of harms doesn't mean there isn't harm," says Dr. Steve Nissen, chief academic officer of the Cleveland Clinic Heart, Vascular & Thoracic Institute. "In the absence of randomized controlled trial data, it's pretty hard to justify."
Expert panel evaluating the merits
There are signs tadalafil could be gaining wider acceptance outside of the online wellness and optimization world. The topic came up recently during the latest meeting of the Princeton Consensus Panel, an influential medical group focused on men's sexual function and cardiovascular health. The group of medical experts — which included Kloner and other preventive cardiologists — arrived at consensus language that low-dose tadalafil is "appropriate" for a subset of men who are at elevated risk of developing cardiovascular disease (搜索) due to the buildup of plaque in their arteries, according to Dr. Martin Miner, who co-chaired the June conference. Their formal recommendations are not yet published.
In an email to NPR, Miner acknowledged some were "hesitant" to endorse this broader use of tadalafil because there were no randomized controlled trials, but ultimately decided to do so based on the existing observational research. "This is not for all men," says Miner, who directs the Men's Health Center at Brown University in Providence, R.I., though he does prescribe it for many of his patients who are at higher risk of cardiovascular disease (搜索).