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The burning flame of desire

How often, how much and how willing? Strong sexual desire can be difficult to contain, while a weaker desire is easily doused. How this delicate machinery actually works is still unknown, but arousal all starts in the brain.

Hot and steamy? Tender and intimate? Or preferably not at all? Sexual desire may be different, but the experience cannot be linked to any specific part of the brain or any particular molecule. It is instead complex interactions that underlie sexual arousal. Several neurotransmitter systems are involved, among others the one that regulates serotonin.

The serotonin system is a well-known target of the most common drugs used to treat depression, SSRIs. They relieve the general sense of uneasiness associated with depression but can dent the sex drive at the same time, since reduced libido is a common side effect.

"It's a paradox, isn't it? At the same time as you increase the zest for life, you happen to reduce the desire for sex. In both cases, this has to do with chemical signalling in the brain, but how this function works when it comes to sexual desire, we don't actually know," says consultant physician Stefan Arver, docent at the Centre for Andrology and Sexual Medicine at the Department of Medicine, Huddinge.

A few years ago, a pharmaceutical company tried to develop a new kind of antidepressant related to SSRIs, but with a different mechanism of action. The substance is called flibanserin, and during the clinical trials for depression it was discovered that the substance, contrary to most other SSRIs, increased libido, especially in women. However, it was not especially effective against depression, and the pharmaceutical company instead chose to try to develop a preparation for treating sexual desire problems in women. The goal was to treat women diagnosed with HSDD, Hypoactive Sexual Desire Disorder, reduced libido and difficulty to become aroused.

The U.S. Food and Drug Administration granted that flibanserin had an effect, but wanted further and more extensive studies, particularly in order to discover any dangerous side effects. The company then shelved the project.

"But it shows that pharmacology can be used to intensify the brain's capacity to experience sexual desire," says Stefan Arver.

This can be also be achieved with levodopa, which is converted to dopamine in the body and is mainly administered to patients with Parkinson's disease. Sick people treated with levodopa can gain a greatly increased sexual desire. If, however, the substance is administered to healthy subjects, there is no effect.

Biological factors

Other biological factors known to reduce libido are thyroid hormone deficiency and testosterone deficiency. Testosterone in particular has a lot of myths associated with it, with many believing that the male sex hormone can be used to increase libido. But it is only in the case of testosterone deficiency that its addition has an effect. Approximately one in ten men seeking treatment for sexual problems has a deficiency of this kind, says Stefan Arver. For other men, with normal testosterone levels, their libido is not affected at all.

Even women can have testosterone deficiency, for example, if their ovaries have been surgically removed. And in women, too, this can cause problems with a lack of libido, something that can be treated with the male sex hormone in lower doses adjusted to women.

Oestrogen levels, on the other hand, play no role for the libido, either in men or women. And the significance of oestrogen is as shrouded in myth as that of testosterone, says Lotti Helström, researcher in obstetrics and gynaecology at the Department of Clinical Science and Education, Södersjukhuset, Karolinska Institutet.

"Many people believe that women have a vaginal dryness during intercourse after menopause. But that's not the case the mucous membranes can become drier in general, but during sexual arousal, the capacity for engorgement and lubrication is the same, regardless of oestrogen levels. It's a message I'm keen to communicate because this misconception is so widespread. Admittedly, it may be necessary to prescribe oestrogen for a woman who has problems with dry mucous membranes in the genital area, but if you want to help her with problems in her sex life, it's better to ask what she and her partner actually do do they take sufficient time to allow her to get wet and aroused? Or is there something else in the relationship that's not really working?" says Lotti Helström.

Communication and interaction for a better sex life

A whole series of studies has shown that is the quality of a relationship that is the most important factor for a functioning sex life. If communication and interaction between the couple works, then sexual problems can be overcome which keeps the desire alive.

This is roughly how Lotti Helström describes the equation. She refers to an American study showing that the couples that continue to have sex like to have it well into old age. Just over half of those who have a partner, and who are in the age group 75-85, have sex two to four times a month. Many of them actually want to have sex more often.

"I think it's good to talk with your patients about sex. There are many patients who are reluctant to raise the issue themselves even though they might have a problem that is possible to sort out," says Lotti Helström.

Studies show that sexual activity decreases in the majority of couples. It is mainly in women that sexual desire is described as decreasing or too low. This is shown, for example, by the most recent national survey of Swedish sexual life, Sex in Sweden, from 1996. The survey demonstrates that 16 per cent of men had a reduced sexual interest over the previous year, something which 38 per cent of them were dissatisfied with. For women, the dissatisfaction was greater one in three women described a reduced sexual desire, which 43 per cent experienced was a problem.

However, Kerstin Fugl-Meyer, Adjunct Professor of Clinical Sexology at the Department of Neurobiology, Care Sciences and Society, exercises caution in the interpretation of these figures. She believes, among other things, that both men and women may have been influenced in their responses by various notions.

"It is not long ago that female sexual desire was looked upon as shameful by many in society, while male desire was taken as a matter of course. If boys and girls learn this from an early age, it can affect how they later describe their own libido. If a woman notices that her husband more often initiates sex, maybe she will herself experience that her libido is low or weaker than the husband's but there is no evidence that female libido should be weaker from a biological perspective. This also disagrees with what I've seen as a treating psychotherapist," says Kerstin Fugl-Meyer.

She also thinks it is misleading to describe sexual desire as an individual factor in people's lives. On the contrary, libido is strongly linked to how life is going in general what is the state of the couple's relationship and family life, how are things at work and how are they doing financially?

It is also common for people who have other sexual problems or dysfunctions or their partners to get reduced libido as a consequence. For example, it is common for women who do not get wet enough, have difficulty reaching orgasm or have pain during intercourse, to also get reduced libido or for their partners to get reduced libido.

Similarly, men with premature ejaculation or erectile dysfunction can get reduced libido as can their partners. Erectile dysfunction, orgasm difficulties and other sexual problems can in turn have several causes. For example, cardiovascular problems affect the erectile tissue of both men and women, and a number of neurological and hormonal disorders, such as diabetes, can also play a role. Furthermore, several drugs can affect the sex life. For example, the hormone preparations usually given following breast cancer can cause pain during intercourse. And here, healthcare has an important but neglected role in helping those who need assistance to maintain their sexuality, according to Kerstin Fugl-Meyer.

"It is well documented that sexual well-being is associated with perceived quality of life. What is needed is a collaboration between several different professions, but there is a lack of time and resources for this. It's unfortunate, because we know that it's possible to help individuals overcome sexual problems and that this significantly increases their quality of life and thus their health," she says.

Together with co-workers, she has recently started a study in which stroke patients will be given help to overcome sexual difficulties. The participants in the study will be offered individually tailored support depending, for example, on whether they are single or have a partner. Conversational therapy in combination with other treatment will be available, and the conversations will focus on the couple's interaction in general.

"We like to think that we in Sweden find it easy to talk about sexual problems, but that is not my experience. Many couples find it difficult to talk about their life together. When you help them put words to their thoughts, they will be able to understand and thereby transform something negative into something positive. And the libido will often return," says Kerstin Fugl-Meyer.

Problematic sexuality may pose an obstacle

But it is not only sexual problems such as erectile dysfunction or orgasm difficulties that might disrupt the sex life. A problematic sexuality may also pose an obstacle. This includes unwanted thoughts, such as sexual fantasies about children, or unwelcome sexual acts, such as in hypersexuality, whereby someone becomes completely engrossed by sexual acts, such as masturbation ten times a day or spending a large part of their waking viewing pornography.

"Hypersexuality is not really libido-driven but anxiety-driven. The sexual acts are performed to alleviate recurrent, severe anxiety. And actually, they only become problematic when they have consequences for the individual or those around them. It could be that someone exposes themselves to great risks through a great number of casual and unprotected sexual contacts or that a relative can no longer cope," says Stefan Arver.

He describes hypersexuality as a risk factor for committing sexual abuse or violence. But most of those seeking treatment at the Centre for Andrology and Sexual Medicine have not committed any crimes, but are voluntarily seeking treatment to overcome their thoughts and behaviours that they themselves feel are wrong.

Together with psychologist Katarina Öberg, Stefan Arver is leading a study where 120 hypersexual subjects will receive CBT treatment in groups in order to overcome unwanted behaviours. The goal is to develop an internet-based, effective treatment for hypersexuality.

The study will be completed next year, but an initial compilation of the subjects has been produced. According to Stefan Arver, this shows that almost all of them were seriously bullied as children or as adults.

"The treatment is about teaching these individuals to manage their anxiety in a different way than through sexuality," he says.

Three truths about sex (according to researchers)

1. The need for closeness and intimacy may increase when you become ill but sexuality does not always mean intercourse.

2. Sexual experience makes it easier to find solutions to sexual problems.

3. The ability to become aroused does not cease. Those who have long been single, or in a relationship without sex, can experience great desire in another relationship.

Text: Annika Lund. Photo: Getty images and others. First published in Medicinsk Vetenskap 3/2013.