Letters to the Editor

AN EVOLUTIONARY THEORY OF PREMENSTRUAL TENSION

The main methodological issues that should be considered in studies of premenstrual changes are discussed. They include: (1) the selection of well-defined groups of subjects who reflect the diversity of subtypes of premenstrual changes (PMC); (2) the confirmation of retrospective reports through daily monitoring of changes by ratings, or by objective procedures when possible; (3) the need to consider the diversity of premenstrual biological changes instead of comparing average levels, since there is a likelihood that different pathophysiological changes are connected with diverse behavioral and mood changes; (4) application of a multivariate, time-related approach to explore the pathophysiology of PMC; (5) the need to exclude placebo responders prior to the active drug phase in treatment trials and (6) the need for such trials to be double-blind, placebo-controlled and, if possible, of a cross-over design. Attention to such issues should lead to increased consistency of findings across studies and eventually to a better understanding of the pathophysiology of PMC and to a rational, effective treatment.

17 women with premenstrual symptoms received bromocriptine (CB 154) and placebo in a double-blind crossover manner. 5 became pregnant and 10 who completed 2 cycles showed significant improvement in breast symptoms, œdema, weight gain, and mood with bromocriptine. Prolactin concentrations were suppressed. In 34 women with premenstrual symptoms, who had been warned of possible increased fertility, bromocriptine 2·5 mg twice daily from the 10th day of the menstrual cycle for 1-11 months gave marked or complete relief. 45 women attending the infertility clinic took 2·5 mg bromocriptine twice daily for 186 cycles; 23 became pregnant, 2 had marked relief and 20 complete relief from premenstrual symptoms. The relief of premenstrual symptoms by bromocriptine may be due to suppression of prolactin concentrations, which may be a major factor in premenstrual syndrome.

Most women of reproductive age have some physical discomfort or dysphoria in the weeks before menstruation. Symptoms are often mild, but can be severe enough to substantially affect daily activities. About 5–8% of women thus suffer from severe premenstrual syndrome (PMS); most of these women also meet criteria for premenstrual dysphoric disorder (PMDD). Mood and behavioural symptoms, including irritability, tension, depressed mood, tearfulness, and mood swings, are the most distressing, but somatic complaints, such as breast tenderness and bloating, can also be problematic. We outline theories for the underlying causes of severe PMS, and describe two main methods of treating it: one targeting the hypothalamus-pituitary-ovary axis, and the other targeting brain serotonergic synapses. Fluctuations in gonadal hormone levels trigger the symptoms, and thus interventions that abolish ovarian cyclicity, including long-acting analogues of gonadotropin-releasing hormone (GnRH) or oestradiol (administered as patches or implants), effectively reduce the symptoms, as can some oral contraceptives. The effectiveness of serotonin reuptake inhibitors, taken throughout the cycle or during luteal phases only, is also well established.