May 9, 2001 (New Orleans) -- It's been a matter of hot debate: Is the very severe type of PMS called premenstrual dysphoric disorder, or PMDD, a real disease or is it just a label some doctors use when talking about normal things that some women might experience? Two new studies using strict criteria to determine the prevalence of PMDD suggest two answers: It is real, and it is significantly disruptive in some women's lives.
The studies were presented here at the annual meeting of the American Psychiatric Association. They looked at both women of child-bearing age and women nearing menopause and suggest that the estimates of the yearly occurrence of PMDD of 3%-5% are roughly correct.
These studies also show that PMDD is very distinct from what is commonly called PMS, which has a yearly occurrence in women of 15%-16%, according to one researcher, Claudio Soares, MD, PhD, of the department of psychiatry at Massachusetts General Hospital, Boston. The two conditions run along a continuum, with PMDD at the much-more-severe end of the spectrum, he says.
He adds that a hallmark distinguishing PMDD from PMS is functional and social impairment. "Some of these women quit their jobs because of their disorder," he tells WebMD.
One study of 513 women age 36 to 44, showed that 6.4% met clinical criteria for PMDD. The survey was part of a study of a larger group of women looking at demographic and lifestyle characteristics associated with the disorder, according to Lee Cohen, MD, and Soares.
Because the study looked only at older premenstrual women, the yearly occurrence may have been found to be higher than what exists in reality. In addition, subjects in the study were followed for only a month; if they were followed for a longer period, the occurrence of PMDD might have been slightly smaller, Soares says.
Preliminary findings from another study of PMDD among females age 13 to 55 found a lower occurrence of the disorder. Of 430 subjects surveyed, less than 2% met criteria for a diagnosis of PMDD, according to the survey sponsored by the National Institute of Mental Health.
But Shirley Ann Hartlage, PhD, says the 430 subjects represent only a small portion of the 2,600 surveyed. As analysis of the total survey sample continues, the true picture of the how many women have PMDD may become clearer and may go up, Hartlage says.
In addition, the preliminary data reveal that some women who do not meet criteria for the disorder still report problems with mood, she says.
Of the 423 women in the sample who did not meet criteria for a diagnosis, 73% said they were less productive and efficient at home, 68% said their symptoms interfered with ability to get things done at home, and 64% said their symptoms interfered with relationships at home.
Smaller -- but still significant -- percentages of women not meeting criteria for a diagnosis of PMDD said their symptoms interfered with social activities, ability to do their work, or with relationships at work, according to the study.
Hartlage says the figures raise the concern that females who experience difficulty with premenstrual functioning may not receive needed treatment because they do not meet stringent criteria for the disorder.
Soares tells WebMD the studies lend credence to two points: PMDD is real, and it can be highly disruptive in women's lives. And he suggests that the true prevalence probably falls somewhere in the middle of the two estimates.
"I think the true prevalence is probably in the 3-to-5% range," Soares says.
So, what should women do if they think they have PMDD?
"Women should have their doctors follow their symptoms using a daily diary," Soares says. "The daily diary of symptoms can help women and their doctors determine if the symptoms are long-lasting symptoms of a chronic underlying depression or anxiety, or if they are really unique to the premenstrual period."
If they do meet criteria for the disorder, they should consult their doctor about the possibility of being treated with antidepressant medication for the 14-day period prior to their period, for two or three cycles.
Response to such treatment is another way to distinguish PMDD from depression, Soares says, because people who have an underlying depression usually require at least two weeks of antidepressant therapy to feel better. But women with PMDD have been shown to improve with intermittent treatment in 14-day periods, he says.