BFRBs are not uncommon among medical students of Karachi. It is therefore imperative to identify the prevalence associated with BFRBs to design interventions to curtail the burden.
Disorder-specific rates in our study ranged from 6.2%-13.3%, which is in agreement with the rates of 12.8% and 10.0% of skin picking and nail biting respectively according to a study conducted in the U.S.. Our study also found greater occurrence among females than males, a finding consistent with previous studies[1, 7, 8]. Literature shows that stressful conditions tend to trigger BFRBs but may not be necessarily associated. Thus this higher prevalence may indicate that females are more prone to stressful conditions and thus tend to get engaged more frequently in BFRBs than males.
As mentioned above, stress may trigger BFRBs. Besides that, other reasons such as socioeconomic factors may also be the cause of stress and anxiety among different sets of students. But since 1) no literature is available proving any such facts, 2) our sample is limited and has no control population and 3) ours is a cross-sectional study which cannot establish cause and effect relationship, therefore we can’t come up with a valid conclusion in this regard.
Overall prevalence of BFRBs in our study was found to be much higher than previous surveys for e.g., according to a study, 13.7% of college students endorsed at least one repetitive behavior that occurred more than five times per day for at least 4 weeks and produced some type of psychological or physical disruption of functioning. Another source gives a lifetime ICD rate of 3.5% in college students while according to a study conducted in United States, 17.1% subjects met criteria for a current ICD. Disorder-specific rates are far greater than other studies, such as 2.7-6.4% of skin picking, mouth chewing and nail biting and disorder-specific rates of 0.4-1.2%, except for trichotillomania, which was 0%.
Research suggests that skin picking occurs in people with a mean age of onset of around 15 years but our study comprised of medical students aged 18 and above, with those indulging in skin picking ranging from 19–26 years with a mean of 22.5 years. Previous studies also identified prevalence of dermatillomania to be approximately 3.8-4.6% of college students[8, 10] 5.4% of a community sample, 4% of college students and 2% of patients seen in a dermatology clinic[8, 11–14], and 1.4%, 4.6% and 3.8% by Nancy J. Keuthen on various occasions[8, 9]. It should be noted here that all these figures are far lower than the prevalence of dermatillomania in our study population that is 9.0%, possibly depicting a greater influence of stress and anxiety on medical students.
Expression of repetitive behaviors has been well documented in the trichotillomania literature. Prevalence estimates indicate a frequency of 2.5% of young adults, being quite lower than the prevalence of trichotillomania found in our study, that is 13.3%. This might be due to inclusion of ‘hair manipulation’ in addition to ‘hair pulling’ in our study.
It is interesting to note that medical students of Karachi were found to indulge the most into trichotillomania, followed by dermatillomania and the least prevalent behavior was onychophagia which is contrary to literature present. This might be due to the fact that in our study, Trichotillomania and Dermatillomania both comprised of two behaviors whereas Onychophagia comprised of nail biting alone, as has been mentioned above.
In one of the few studies to address the issue of BFRBs, college students were categorized as having a repetitive behavior (habit) if the student reported engaging in a behavior two or more times per week. Using this relatively lenient criterion, Hansen et al. found that nail biting occurred in 63.6% of the sample. A subsequent study used more stringent criteria for identifying repetitive behaviors in college students. Stating that the repetitive behavior had to occur at least five times per day to be classified as a habit, it was found that 21.8% of the sample engaged in habitual chewing on mouth, lips, or cheeks and 10.1% engaged in habitual nail biting.
As discussed earlier, BFRBs may produce a variety of physical sequelae. Thus, to accurately ascertain the extent to which BFRBs are an actual diagnosable problem, not only must data be collected on how frequently these behaviors occur in an individual but also and more importantly the extent to which these behaviors produce some type of impairment be considered. Unfortunately, the Hansen et al. (1990) and Woods et al. (1996) did not incorporate this variable into their operational definitions when determining the prevalence of BFRBs. The tool that we have used for our study, the ‘Habit Questionnaire’ follows criteria that cover all factors and variables associated with BFRBs and thus give a better estimate of its prevalence with greater accuracy. Even after following such strict criteria, prevalence in our study was quite high, pointing towards the fact that medical students of Karachi are greatly prone to such negative behaviors.
There are a number of aspects of our study which limit conclusions. Due to excessive workload on medical students, the specifications of questionnaires might not have been accurately filled or due to extra stress on students having their exam season and vice versa, their BFRBs might have been affected which might have affected the overall results. Also, since ours is a cross-sectional study, cause and effect relationship for the identified associated factors could not be established. Because we have carried out this study among medical students only, we cannot give any absolute predictions of prevalence among the general population. Besides that, we cannot comment on the age and gender distribution of BFRBs since medical students fall into a particular age group only and also because the majority of students at the above mentioned study setting were females, it may have affected gender distribution of such behaviors. Also, we have not considered co-morbidities of different behaviors which limit conclusions.
This study offers a number of avenues for future research. Additional research should be conducted to establish prevalence rates among different populations including children, adolescents and elderly, and among populations with cultural differences. It may also be useful to examine the general phenomenology of BFRBs among typically developing persons, including possible co-occurring psychological symptoms such as anxiety or negative affective states. Studies should also be conducted to find out the factors associated with BFRBs and its various possible consequences. Doing so may elucidate important components of treatment and methods to avoid engaging into such behaviors that are so physically and socially disadvantageous.