It is instead hypothesized that women with PMDD are more sensitive to normal levels of hormone fluctuations, predominantly estrogen and progesterone, which produces biochemical events in the nervous system that cause the premenstrual symptoms. These symptoms are more predominant in women who have a predisposition to the disorder.It is apparent that the premenstrual disorders are biologically driven and are not only psychological or cultural phenomena. PMDD has been reported by menstruating women worldwide, indicating a biological basis that is not geographically selective. Most psychologists infer that this disorder is caused by both a reaction to hormone flux and also genetic components. There is evidence of heritability of (retrospectively-reported) premenstrual symptoms from several twin and family studies done in the 1990s, with the heritability of PMDD proving to be about 56%. Genetic factors
While whether or not this disorder has a specific genetic basis is still being discussed in the academic community and the possible genetic factors contributing to PMDD have yet to be thoroughly researched, there has recently been multiple genetic factors identified that contribute to the moodiness, depression, irritability, increased appetite, trouble sleeping, acne, fluid retention, headaches, nausea, and other symptoms that are all associated with this disorder. Many studies have noted that a polymorphism of the brain-derived neurotrophic factor gene (BDNF), a gene that helps support neurons in their function and survival in the brain by creating a protein that helps in the growth, maturation, and maintenance of these cells, may play a role in causing PMDD symptoms.
Suicidality in Premenstrual Dysphoric Disorder
Previous links to suicidality and PMS have been made, but women with PMDD are more likely still to consider and attempt suicide even when controlling for mental health comorbidities. Despite the increase in suicidal ideation and attempts in this population, the data currently suggests that suicidal ideation or action is not more likely to occur during the late luteal phase when PMDD symptoms would occur. It is difficult to study whether treatment reduces suicidality because of the multifaceted reasons provided for suicidal ideation. However, treatment has been well documented to reduce physical and emotional symptoms of PMDD. Diagnosis
Diagnostic criteria for PMDD are provided by a number of expert medical guides. Diagnosis can be supported by having women who are seeking treatment for PMDD use a daily charting method to record their symptoms. Daily charting helps to distinguish when mood disturbances are experienced and allows PMDD to be more easily distinguished from other mood disorders. With PMDD, mood symptoms are present only during the luteal phase, or last two weeks, of the menstrual cycle. While PMDD mood symptoms are of a cyclical nature, other mood disorders are variable or constant over time. Although there is a lack of consensus on the most efficient instrument by which to confirm a PMDD diagnosis, several validated scales for recording premenstrual symptoms include the Calendar of Premenstrual Experiences (COPE), Daily Record of Severity of Problems (DRSP), and Prospective Record of the Severity of Menstruation (PRISM).