Evaluation of gonadotropin-releasing hormone agonist treatment for prevention of menstrual-related attacks in acute porphyria.

OBJECTIVE: To describe the benefits and adverse effects of gonadotropin-releasing hormone (GnRH) agonist treatment for prevention of recurrent menstrual attacks in women with acute intermittent porphyria and variegate porphyria. To describe concomitant add-back therapies with estradiol and progesterone and describe their benefits and adverse effects.
DESIGN: A retrospective follow-up with questionnaires, interviews and medical records.
SETTING: Out-patient care at the Umeå University Hospital in Sweden. POPULATION: Sixteen Caucasian women with DNA-diagnosed porphyria and menstrual-cycle-related porphyria attacks were treated with GnRH agonists during 1984-2000. Fourteen women participated. The mean age when treatment started was 33 years (17-48 years). The duration of treatment varied between 5 months and 9 years.
METHODS: GnRH agonists were administered by the intranasal route or by injections. To reduce menopausal symptoms, add-back therapy with low doses of estradiol was administered, and for endometrial protection progesterone was usually administered. MAIN OUTCOME MEASURES: Treatment effects and adverse events as detected in questionnaires, interviews and medical records.
RESULTS: Eleven women reported benefits from GnRH agonist treatment with less intense and/or less frequent porphyria attacks, and in four of them attacks almost disappeared. Two women reported no change. One woman had only temporary improvement. Porphyria attacks were triggered by solely estradiol add-back in two women and in five of nine women when progesterone was given.
CONCLUSIONS: GnRH agonist treatment can ameliorate menstrual-cycle-related attacks of porphyria. Dose findings for GnRH agonists and add-back regimes especially for progesterone are intricate.