Premenstrual Dysphoric Disorder (PMDD)

The exact cause of both premenstrual dysphoria disorder and premenstrual syndrome is unknown. If women with either condition have all of their ovarian and pituitary hormones measured there does not seem to be an abnormality in the actual level of hormones. It is therefore thought there may be a number of possible causes. The interaction between ovarian hormones and neurotransmitters in the brain is one theory. Neurotransmitters send messages through the brain and are known to be to some extent hormone dependent.

There are a number of neurotransmitter groups that operate within the brain. The most likely system to be involved with mood changes is the serotonin system but there are also chemical systems such as GABA and opioid systems which all interact. PMDD may therefore be not due to any specific level of a hormone but rather the sensitivity of these systems to particular hormones. A number of treatment options rely on this theory such as the use of medications that interfere with serotonin levels, a group of antidepressants.

The American Psychiatric Association diagnose premenstrual dysphoria disorder on the basis of five or more significant symptoms. These symptoms are often debilitating and interfere with a woman’s quality of life, including their relationships, family interactions, the workplace and recreation.

The symptoms that are considered characteristic of premenstrual dysphoria disorder include

• Significant depression and anxiety
• Mood lability
• Suicidal thoughts
• Anger
• Irritability
• Brain fog
• Dissociation – women explain feeling as if they are standing outside their body looking at someone who is not them
• Avoidance behaviour – women avoid interaction with family members, friends and social events

The number of females that experience premenstrual dysphoria disorder varies between studies but lies somewhere between 3-7%. Premenstrual dysphoria disorder has been shown to be more common in women who have had previous depression and anxiety (including postnatal depression), current or previous ADHD, autism spectrum disorder or teenage eating disorders.

For these reasons, women with PMMD have often sought help from a psychiatrist or psychologist.

It is important that PMDD is distinguished from other physical and psychological conditions that can produce similar symptoms. The differential diagnoses include mood and anxiety disorders including bipolar disorder, medical conditions especially thyroid disease and chronic anaemia. It is therefore important to exclude these possible medical conditions on appropriate blood testing. All patients with significant premenstrual dysphoria disorder, especially patients who need to be on antidepressants or other mood altering medications should be under the care of a psychiatrist.

A key indication that you are dealing with premenstrual dysphoria disorder and not a different psychiatric disorder is the cyclical nature of the symptoms with premenstrual dysphoria disorder.

Several medical therapies have proven effective in managing PMDD symptoms. These include antidepressants (SSRIs). Up to 75% of women report relief of symptoms when treated with SSRI medications. In particular, there are randomised controlled trials in PMDD where the drugs used were sertraline, fluoxetine or citalopram.

A second group of antidepressants involving noradrenaline are called the SNRIs and these include drugs such as duloxetine which has also been used successfully with premenstrual dysphoria disorder. More recently, agomelatine (Valdoxan) and a mood stabilising drug lamotrigine have been shown in studies to be effective with premenstrual dysphoria disorder.

Secondary Treatment Options: Hormone Regulation Medications

The second line of treatment for PMDD involves medications that regulate hormones. This keeps hormone levels constant daily, whereas natural hormone production (endogenous hormones) can vary by up to 40% per day.

In particular, two oral contraceptives taken continuously to prevent periods have shown to be effective in a number of studies in up to 80% of patients. The two contraceptives are Zoely which contains natural oestrogen (oestradiol valerate) and Yaz. Both these drugs suppress ovulation, normalise hormone levels on a day to day basis and usually prevent periods when the hormone tablets are taken continuously.

Oral Contraceptives in PMDD Management

Gonadotrophin-releasing hormone (GnRH) analogues have also been used to treat PMDD. These drugs suppress ovarian oestrogen production by inhibiting the secretion of regulatory hormones from the pituitary gland. This cessation of menstrual periods can lead to oestrogen deficiency, so these drugs are usually used alongside hormone replacement therapy with both oestrogen and progesterone. Occasional side effects include osteoporosis, even with oestrogen replacement, so regular bone density studies are necessary to measure bone strength. The safety of using these drugs long-term is still uncertain, with ongoing studies limited to two years at present.

There is no doubt that many patients benefit from the assistance and expertise of psychiatrists with an interest in women’s health and in particular, premenstrual dysphoria. Similarly, psychologists and other therapists are often invaluable.

It is also important to consider simple lifestyle changes such as regular exercise, an appropriate diet and the use of meditation and mindfulness can all be invaluable adjuncts to treatment.