Using blinded ratings by the first rater, 14 (22.2%) of the 63 men were rated as having muscle dysmorphia. These men did not significantly differ from the 49 men without muscle dysmorphia on demographic indices (). BDD severity scores and delusionality (BABS score) also did not differ significantly between the groups.
Demographic and clinical characteristics of muscle dysmorphic versus non-muscle dysmorphic BDD participants
Of the 14 men with muscle dysmorphia, 12 (86%) had additional non-muscle-related BDD. Of these 12 men, 9 had current muscle dysmorphia and current non-muscle-related BDD, 2 had past muscle dysmorphia and current non-muscle BDD, and 1 had past muscle dysmorphia and past non-muscle BDD. Men with muscle dysmorphia reported significantly more body areas of concern than comparison men. However, when comparing only non-muscle-related body parts (i.e., excluding concern with the chest, calves, stomach, arms, or any other body part that the subject indicated was “too small” or “not muscular enough”) the two groups were similar (). Among the men with muscle dysmorphia, the most common area of concern, as expected, was muscularity, followed by hair (n = 9) and skin (n = 8). Hair and skin were the most common concerns for the comparison men. As would be expected, men with muscle dysmorphia were more likely than comparison men to lift weights excessively (10 [71%] versus 6 [12%]; p < 0.001), exercise excessively (9 [64%] versus 5 [10%]; p < 0.001), and diet (10 [71%] versus 13 [27%]; p = 0.009). However, other BDD-related behaviors were similar: comparing, mirror checking, and camouflaging were the most common behaviors in both groups.
Men with muscle dysmorphia had poorer scores than comparison men on all quality-of-life measures, with two of four measures (the Q-LES-Q and SF-36 Mental Health subscale) reaching statistical significance, with large effect sizes. Men with muscle dysmorphia were also significantly more likely to report a suicide attempt. As hypothesized, men with muscle dysmorphia were significantly more likely to have abused anabolic-androgenic steroids—but unexpectedly, we found that they also exhibited a significantly higher lifetime prevalence of substance use disorders. Also as predicted, a higher proportion of men with muscle dysmorphia had a lifetime eating disorder (small–medium effect size), but the between-group difference was not statistically significant.
The second, independent blinded rater diagnosed muscle dysmorphia in 18 (28.6%) of the 63 men—representing the same 14 men diagnosed as having muscle dysmorphia by the first rater, plus 4 additional cases. Thus, the raters exhibited 93.6% agreement, with kappa = 0.83. We repeated the comparisons in using the second rater’s muscle dysmorphia diagnoses, which produced very similar results (all findings significant at the p < 0.05 level remained significant at this level in the second analysis, and all nonsignificant findings remained nonsignificant).