Study on rare sexual arousal disorder points at cause -- and new cure

From the orgasm’s deep evolutionary roots in the brain, to the modern-day orgasm gap, sexual climax is as perplexing for scientists as it is for the rest of us. But for a select few, these feelings are all too familiar.

Their extremely rare condition, persistent genital arousal disorder, is estimated to affect some 1 percent of women globally. Strangely, just a handful of men are known to have the condition. People with the disorder experience frequent orgasms that can happen at any time, without warning or prompting — and it leads to misery, not pleasure. For years, scientists have written off the condition as psychological, and treatment has centered on (largely unsuccessful) behavioral therapy. But a new study reveals that the disorder likely isn’t psychological at all.

Instead, it may be rooted in neurology — caused by lesions to the base of the spine. That’s the upshot of a paper published this week in the journal PAIN Reports. And already, the finding has led to a cure in at least one person.

Most physicians don’t know about the disorder, and scientists believe people with the condition might not even tell their doctor about their symptoms anyway, out of embarrassment. The findings offer a roadmap to potential treatments that target the base of the spine — and shed new light on this little-understood and often ignored condition.

Pursuing persistent genital arousal disorder

In a study of 10 women with the disorder, scientists found evidence to suggest that the condition is caused by “nerve entrapment”, which is when a nerve deep in the spinal cord is continually stimulated by an outside force.

The paper jibes with a theory that the disorder stems from Tarlov cysts — tiny sacs of cerebrospinal fluid that can develop form on sensory nerves in the sacral dorsal area of the spinal cord (a collection of bones at the base of the spine).

Those sacs apply pressure to these nerves which can lead to lower back pain (like sciatica) some people. For people with the condition, the sacs may be stimulating nerves related to sexual arousal. Four of the people in the study had the cysts.

But the findings also suggest that cysts aren’t the only thing that could cause this disorder: one participant had a herniated disc, which also pinched crucial nerves. Another had abruptly stopped taking duloxetine, an anti-depressant (withdrawal, the team notes was probably responsible for her symptoms.) Gradually weaning the participant back on, and then off, the medication cured her condition.

Taken together, these results suggest that lesions, like Tarlov cysts, are to blame for the condition — not psychology. Targeting those legions might prove an effective treatment.

To test this theory, the scientists surgically removed Tarlov cysts in one participant, curing their symptoms. A procedure in another participant reduced — but did not eliminate — some of the pressure in the lower back, which did seem to help. But for another participant, surgery wasn’t helpful, suggesting more work is needed to develop an effective treatment from the results.

Misery, not pleasure

In this study, it quickly becomes obvious how difficult life with the disorder can be. In a Reddit AMA, one participant described it as “a painful and embarrassing medical condition.”

Another participant reported having as many as 30 spontaneous sexual arousals daily. Once, these arousals escalated to orgasm in front of a live audience at a hospital. Six participants with sexual partners said their condition affected their relationships, and effectively ended their sex lives. All the participants said the condition either exacerbated existing anxiety and depression or led to new cases of either.

Sexual arousal in PGAD is involuntary genital arousal. It’s not a compulsion, but arousal that emerges spontaneously.

Some people with the condition, constantly plagued by orgasms and mocked for it, have taken their own lives.

Masturbation sometimes provided short-term relief for some participants in this study, but it didn’t even help everyone. Only 20 percent saw their symptoms relieved by masturbation, which wasn’t even pleasurable for at least one person.

A misunderstood condition — solved?

This is not the first attempt to explain this rare and debilitating disorder. But until now, the condition has mostly been investigated by psychologists. But for the study participants, psychiatric treatment was “universally ineffective.” Across the sample there were seven psychiatric hospitalizations, and one person received 17 sessions of electrotherapy — all to no avail.

Until 2001, the condition was lumped in with other diagnoses, like hyper-sexuality disorders. It received its own diagnosis only after a 2001 paper, which described people with involuntary genital arousal, characterizing it as a “newly discovered pattern of female sexuality.”

Of the study participants, just one in five said their doctors had recognized their symptoms for what they were. Instead, most of the women in the study were self-diagnosed using internet resources.

Partially because of the large community of patient-led, support group websites, scientists believe that there are far more people with this condition out there than we may think. By targeting the lower back instead of the brain, the scientists say, they may be able to relieve these symptoms for good — offering a new lease of life to people with the disorder.

This study suggests that back surgery may not help everyone with the condition, but an alternative treatment that targets the biology behind the disorder signals a big step forward, the study authors note. It’s also early evidence that people with the disorder may not have to live their lives on high alert for spontaneous sexual arousal. If these results are validated and new treatments developed, they may soon be able to take back control of sexual pleasure.

Abstract:

Methods: The IRB waived consent requirements for this retrospective university-hospital study. We extracted and analyzed neurological symptoms, test, and treatment results from all qualifying participants’ records and recontacted some for details.

Results: All 10 participants were female; their PGAD symptoms began between ages 11 to 70 years. Two patterns emerged: 80% reported daily out-of-context sexual arousal episodes (#30/day) that usually included orgasm and 40% reported lesser, often longer-lasting, nonorgasmic arousals. Most also had symptoms consistent with sacral neuropathy—70% had urologic complaints and 60% had neuropathic perineal or buttock pain. In 90% of patients, diagnostic testing identified anatomically appropriate and plausibly causal neurological lesions. Sacral dorsal-root Tarlov cysts were most common (in 4), then sensory polyneuropathy (2). One had spina bifida occulta and another drug-withdrawal effect as apparently causal; lumbosacral disc herniation was suspected in another. Neurological treatments cured or significantly improved PGAD symptoms in 4/5 patients, including 2 cures.

Conclusions: Although limited by small size and referral bias to neurologists, this series strengthens associations with Tarlov cysts and sensory polyneuropathy and suggests new ones. We hypothesize that many cases of PGAD are caused by unprovoked firing of C-fibers in the regional special sensory neurons that subserve sexual arousal. Some PGAD symptoms may share pathophysiologic mechanisms with neuropathic pain and itch.