Migraines in Youngsters May Fade as Time Goes By

PALERMO, Italy, Oct. 26 -- It may take 10 to 20 years, but as children and teenagers reach adulthood, migraine headaches often disappear, alter, or become less severe, according to researchers here.

Of 55 youngsters, ages 11 to 14 years, who had migraines at the beginning of the study in 1989, 10 years later, the headaches remitted in 38.2% (21) and transformed to tension-type headaches in 20% (11), Rosolino Camarda, M.D., of the University of Palermo here, and colleagues, reported in the Oct. 24 issue of Neurology.

Nevertheless, for 41.8% (23) of the patients the migraines persisted, said the investigators.

The findings came from a population-based survey of 1,686 school children in the town of Monreale. The analysis included 55 children, of 80 with migraine headaches at the start of the study, who were eligible for follow-up in 1999.

The children in the original group of 80 were classified according to the presence of migraine without aura migraine (34), with aura (9), nonclassifiable headache (15), and migrainous disorder (22). Migraine diagnoses were based on the International Headache Society (IHS) criteria.

In contrast with other investigators, the researchers said, they did not find that female sex and age of headache onset were prognostic markers. Still, they said, these differences might be due to the small size of the study, its limited statistical power, and the limited age range of the participants.

On the other hand, family history of migraine significantly predicted the 10-year persistence of migraines, with a sevenfold increased risk of persistence over 10 years among those with a first-degree relative with migraine (odds ratio =7.0, 95% CI, 1.7-26.8).

When only patients with or without aura were evaluated, the familial risk for migraine without aura also tended to persist (OR = 5.0, CI, 1.2 - 20.9), the researchers wrote. One fourth of subjects with migraine without aura persisted in the same HIS classification after 10 years, whereas migrainous disorder and nonclassifiable headache tended to change, the researchers said.

Migraine is a complex disease in which constitutional and environmental factors play different roles, probably accounting for the differences in migraine phenotypes, the researchers said. The fact that familial disposition for migraines predicted a poorer outcome in subjects who had migraine without aura suggests that genetic factors play a role. On the other hand, they said, multiple environmental factors could be more relevant in determining other migraine headaches.

The strengths of this study, Dr.Camarda wrote are its population-based long-term prospective design.

On the other hand, the researchers noted several methodologic limitations. First, they said, the original sample was diluted into very small patient groups, although the findings were for the most part similar to those previously described in other long-term follow-up studies. Also, it was not possible to control for possible psychiatric comorbidity, which might play a role in the persistence of the headaches.

Finally, the researchers acknowledged that the family estimates might have been overestimated as a result of recall bias.

The variability of the prognostic figures for migraine headaches in adolescents probably reflects differences in the demographic characteristics of study populations and case definitions, especially the validity of the older International Headache Society (IHS) criteria used here, the researchers said.

In conclusion, they wrote that further population-based longitudinal studies of adolescents, conducted on larger samples with the more sensitive criteria of the International Classification of Headache Disorders (2^nd ed; ICHD) are warranted.