Anorexia Nervosa Among Finnish Men

Anorexia nervosa (AN) is believed to be rare among men. However, results from a recent study of Finnish twins suggest that AN in males may be more common, more transient, and accompanied by more comorbidity than previously thought.

Dr. Anu Raevouri, of the University of Helsinki, and colleagues at Columbia University, New York City, Parnassia Babo Psychiatric Institute, the Hague, Netherlands, and at the National Public Health Institute and Helsinki University Central Hospital, Helsinki, used data from 2,122 Finnish twins to study the incidence, prevalence and comorbidity of AN among males (plOS one 2009; 4:e4402). In the FinnTwins Study, virtually all twins born between 1975 and 1979 were assessed at ages 16, 17, and 18, then again at 22 to 28 years of age. Of this group, men who reported or suspected ever having had an eating disorder (20 men) and their male co-twins (11 men) were invited to participate in diagnostic telephone interviews. DSM-IV criteria for AN, excluding amenorrhea, were used to make the diagnosis. One female co-twin of a male proband with AN was also interviewed.

A transient disorder with significant comorbidity

The researchers reported four important findings. First, although AN in adolescent and young men from the community was transient, it was also accompanied by significant psychiatric comorbidity, which was also noted in their co-twins. The pattern of common familial diathesis of AN and affective and anxiety disorders, as well as obsessive-compulsive personality disorder, had earlier been demonstrated only among females in the clinical samples. The authors noted that the co-twins of the male probands differed remarkably from those of female probands in the same twin cohort, whose co-twins were mostly healthy. They feel this supports the hypothesis by Michael Strober and colleagues that in order to develop an eating disorder, men require a stronger genetic predisposition and/or more adverse environmental factors than do women (Int J Eat Disorder 2001; 29:263). Crossover to bulimia nervosa occurred in two probands.

To develop an eating disorder, men require a stronger genetic predisposition and/or more adverse environmental factors than do women

The second finding was that, compared to young males from the general population, symptoms of body dysmorphic disorder (BDD) were frequent in the co-twins, suggesting a common familial diathesis for AN and BDD. After AN, one proband had BDD symptoms, including high muscle dissatisfaction, excessive gym training, and use of muscle-building supplements.

The third finding was that AN in young men was more common than suggested by previous reports in other areas of the world. Dr. Raevouri and colleagues also note that these data aren’t really comparable because other studies have included a wider age range. The incidence of AN among women aged 10 to 24 years in the twin cohorts was 140 per 100,000 person-years, or about 9 times greater than in men.

Approximately 1 of 400 boys had AN by young adulthood. However, the authors reported that the illness is rarely encountered in clinical settings, perhaps because of the short duration of the illness, treatment delay, and fear of social consequences following the diagnosis. The authors think their screening was probably suboptimal, and that the prevalence of 0.24% was probably an underestimate than an overestimate of the prevalence of AN among men in that population. Most of the men who screened positive for AN had disordered eating but not a diagnosable eating disorder. A few who reported that they had an eating disorder actually had another severe mental illness, such as schizophrenia.

The authors found no cases of bulimia nervosa without previous AN. The authors feel that the less-than-perfect sensitivity of their screening method led some men to conceal their eating disorders or other related problems, due to their fear of stigmatization.