Response

In their guest editorial ‘Premenstrual exacerbation of psychiatric symptoms: from misdiagnosis to management’, Kulkarni and Mu listed or recommended a number of strategies for managing premenstrual exacerbation of existing mental illnesses (PME). ^{Reference Kulkarni and Mu1} In my view, some of these strategies do not align with or fully represent the cited literature, or have not been taken in context.

First, the suggested strategy of using the combined oral contraceptive pill of 17-beta oestradiol and nomegestrol acetate for potentially managing PME, was based on a small preliminary pilot study of 49 women with premenstrual dysphoric disorder or PMDD (of whom only 31 women adhered to the pill throughout the follow-up period). ^{Reference Robertson, Thew, Thomas, Karimi and Kulkarni2} The reported primary outcome for this study was a subjective non-standardised self-report of mood symptoms with no known prior use in literature. This quite limited the generalisation and replicability of the reported treatment benefit. Further, the majority of combined oral contraceptive pills, which were compared to placebo for managing premenstrual symptoms in published clinical trials, were drospirenone containing. ^{Reference de Wit, de Vries, de Boer, Scheper, Fokkema and Janssen3} The treatment effect of these pills on premenstrual mood symptoms was not superior to placebo. ^{Reference Ma and Song4} In their clinical practise guidelines, the American College of Obstetricians and Gynecologists recommends that when premenstrual depression is the primary concern, other available managements (through shared decision making) with proved efficacy can be used as alternatives to combined oral contraceptive pills. ⁵

Second, the authors stated that the dose of selective serotonin reuptake inhibitors (SSRIs) may need to be increased premenstrually (intermittent treatment) with careful monitoring of withdrawal symptoms. This strategy was cited from a systematic review and meta-analysis of randomised trials which compared the effect of intermittent SSRIs dosing to continuous dosing, on response rate and symptom reduction. ^{Reference Reilly, Wallman, Clark, Knox, Craig and Taylor6} This review found the odds of treatment response were equal for intermittent or continuous SSRIs dosing (odds ratio is 1 or null). Additionally, the symptom reduction standardised mean difference between the two dosing arms was 0.04 (negligible or nil). Therefore, the superiority of intermittent SSRIs dosing during the luteal phase, compared with continuous dosing, was not established. The recommendation to use intermittent SSRIs dosing premenstrually is not supported by this review.

Third, the authors’ suggestion that agomelatine might be a useful antidepressant for premenstrual disorders, was cited from a small pilot study which investigated plasma melatonin rhythm among five women with PMDD. ^{Reference Shechter, Lespérance, Ng Ying Kin and Boivin7} The study did not report on the use of agomelatine during the luteal phase (intermittent or otherwise). In fact, the study unequivocally concluded that the effect of agomelatine on endogenous melatonin secretion among women with PMDD was still undetermined. There was no such recommendation about the use of agomelatine premenstrually.

In short, the recommended management strategies for PME, using a combined oral contraceptive pill or intermittent dosing with SSRIs or agomelatine premenstrually, are not consistent with the cited literature. These strategies require further clarification and should be considered with caution.