Over the last 15 years, the abbreviation "PMS" has become a well-worn part of Americans' everyday language. The term is tossed around in conversations at home, and even the office, sometimes to describe a generally cranky state of mind. But for some women, PMS, or premenstrual syndrome, is a disabling condition involving multiple physical and emotional symptoms. Although most women are able to manage premenstrual symptoms by getting more sleep or drinking less caffeine, or at least weather the symptoms without too much trouble, others have severe PMS, and a smaller group of women have premenstrual dysphoric disorder, or PMDD.
Women with PMDD experience severe symptoms that disrupt their lives by affecting their relationships and ability to perform their jobs or schoolwork. Although many questions about PMDD remain unanswered, researchers such as Ellen Freeman, PhD, a research professor and codirector of the Human Behavior and Reproductive Unit in Obstetrics and Gynecology at University of Pennsylvania in Philadelphia, are studying treatments for PMDD, such as serotonin reuptake inhibitor (SSRI) antidepressants and oral contraceptives. Below, Dr. Freeman explains the difference between PMS and PMDD, and reviews available treatments.
What is PMS?
PMS involves mood, behavioral and physical symptoms that occur in the days before the menstrual period. The most common symptoms are usually irritability, anxiety, tension, mood swings, breast tenderness, bloating and swelling. It's likely that nearly all women who seek treatment have at least two or three symptoms. And they probably have a mixture of mood and physical symptoms.
What is PMDD?
Unlike PMS, PMDD is a condition that is classified as a disorder in the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition. A woman must have at least five symptoms from a list of 11 symptoms. These symptoms must occur premenstrually and not other times: They must abate or go into remission during the menstrual period and then there's a symptom-free interval. So PMDD is not just a magnification of a psychological disorder such as depression. For a diagnosis of PMDD to be made, it's also required that these symptoms cause impairment in functioning of some sort, and that they be confirmed with daily symptoms ratings for at least two menstrual cycles. This confirmation is done with a symptom diary in which the woman records her symptoms.
How common is PMDD?
The US estimate is now around 5 percent. I think there's considerable information that suggests that another 15 percent or more are so bothered by their symptoms that they go to doctors for treatment. If they don't meet the criteria for PMDD, but they have four symptoms, that doesn't mean they have nothing. They have severe PMS, and they need to be helped. They're unrecognized in an official way because they don't have PMDD.
When are women most likely to have PMS or PMDD?
In theory, PMS and PMDD can occur any time during the reproductive lifetime between the onset of the menstrual cycle and menopause. The treatment studies have overwhelmingly involved women in their 20s and 30s, though that may just be the age of women willing to volunteer for studies. There's not a lot of solid scientific data about the course of the disorder, but it does appear to be chronic. Once a woman has PMDD, it's probably not going to go away until she starts approaching menopause, or until she's postmenopausal.
What are some of the theories about what causes PMDD?
No one really knows what causes PMDD. The biological theory is that some women have a sensitivity to the normal hormonal changes that are linked to the menstrual cycle. And there seems to be some link between the hormonal changes and the serotonin system in the brain; serotonin is a neurotransmitter, or brain chemical, that is associated with a lot of mood disorders.
What are the treatment options?
The consensus right now is that selective sertonin reuptake inhibitor (SSRI) antidepressants such as Prozac or Zoloft are first-line treatments, meaning that they should be recommended first. These antidepressants can be taken for the full cycle or during the luteal phase of the menstrual cycle only, which is the time beginning with ovulation and ending with the next menstrual period. Studies show that both approaches are effective in terms of symptom improvement. It's an individual decision for various reasons. Some women want to take less medication and find it personally useful to take it only in the luteal phase when they have symptoms. Other women may have more symptoms than they thought all cycle long, so they feel better if they take the drug all cycle long. And some women think it's just easier to take a pill every day than it is to remember when to start taking it.
Oral contraceptives are sometime given for PMDD, but there have not been a lot of studies to demonstrate whether they are effective. And oral contraceptives are hardly a uniform treatment. There are many different combinations. New studies suggest that some new formulations may be beneficial, possibly because of the progestin they use, the level of estrogen, or because the placebo pills that normally allow for a monthly menstrual period are not taken. But these data have yet to definitively demonstrate their effectiveness as a PMDD therapy.
Is treatment appropriate for people with severe PMS who don't necessarily qualify for PMDD?
Some of the studies have looked at women who would be described as having severe PMS; they did not meet the criteria for PMDD because they didn't have five PMDD symptoms. These studies indicate that treatment is effective in these women.
Can lifestyle changes ease symptoms, both for PMS and PMDD?
There are numerous lifestyle changes that have been advocated for the problem and a lot of them are probably very helpful. How helpful may have something to do with how severe the symptoms are. For women who have moderate to mild symptoms, lifestyle changes may take care of it. Again, I think it's an individual question, and there's very little downside to trying; there may be no downside to trying.
Lifestyle changes to manage symptoms can include a healthy diet; less caffeine and alcohol; not smoking; regular exercise and stress reduction. One large study that compared 1200 mg of calcium daily to a placebo showed that calcium was very helpful in alleviating premenstrual symptoms. And there are some preliminary data that suggest a carbohydrate-rich beverage that was specially created to help depressive and mood symptoms in PMS helped relieve symptoms.
Do you think more studies are needed?
PMDD is a very complex disorder. The SSRIs work, but only in about 60 percent of patients, so there are another 40 percent that aren't being helped and we don't know why. It's possible that another class of medication or other forms of treatment might be helpful, so I think there's lots of room for more studies.
