To the Editor: Concordance rates of up to 80% have been reported in monozygotic twins with bipolar disorder (1); significantly elevated concordance rates among monozygotic twins with migraine headaches have also been reported (2). There is evidence that the prevalence of migraines is higher in patients with bipolar disorder (3). We report on a pair of monozygotic twins concordant for bipolar disorder and migraines who were successfully treated with carbamazepine.
Ms. A and Ms. B were 29-year-old twins who were born 6 weeks premature. Their mother and a younger sister suffered from migraines, a maternal aunt from bipolar disorder, and a paternal aunt from unipolar depression. Ms. A was left-handed, and Ms. B was right-handed.
Ms. A had suffered from weekly migraines since she was 13, and Ms. B had had them every 2 weeks since she was 14. The headaches were unilateral, were pulsating, lasted more than 4 hours, and were accompanied by loss of appetite, nausea, vomiting, photophobia, and phonophobia. Flashing lights, visual scotomata, and occasional fortification spectra preceded the headaches by half an hour.
Ms. B had major depression with marked feelings of guilt when she was 14 and required hospitalization. A second depressive episode occurred when she was 19, and at age 24 she had her first manic episode, which included flights of ideas and grandiose delusions with religious content. Three years later, a florid manic episode cut short a vacation in Europe. Since then she has been maintained with carbamazepine, 400 mg b.i.d., has remained symptom free, and has worked full-time as a nurse.
When she was 15, Ms. A apparently had a week-long, mild manic episode, which went unrecognized. At age 19 she had major depression; she had a manic episode when she was 21. Lithium therapy was begun, but it had to be discontinued because of severe side effects. Ms. A had a manic episode followed by depression when she was 25. This illness lasted for 6 months; it was during this episode that carbamazepine treatment was initiated. A year later Ms. A had another major depressive episode in which she took an overdose of carbamazepine; however, since then she has remained well on a regimen of carbamazepine, 400 mg b.i.d. After the introduction of carbamazepine as a mood stabilizer, both sisters experienced a marked reduction in the frequency of their migraines.
To our knowledge, this is the first report of monozygotic twins concordant for bipolar disorder and migraine. It is of interest that both conditions appear to have responded to treatment with carbamazepine. This supports a possible common pathogenesis for the illnesses.