Dental Students’ Perception, Awareness and Knowledge About HPV Infection, Vaccine, and Its Association with Oral Cancer: A Multinational Study

Introduction

Oral squamous cell carcinoma comprises a group of malignancies that manifest in various regions of the oral cavity and are the 11th most common cancer worldwide.¹ The global incidence of these malignancies is 4 per 100,000 people, and they form a major economic burden.² According to Globocan data, the 5-year prevalence of oropharyngeal cancer (OPC) globally is 2.2% in Africa, 37.6% in Asia, 16.9% in North America, 8.6% in Latin America and the Caribbean and 33.4% in Europe, respectively.³

The etiology for oral cancer is multifactorial, including exposure to ultraviolet radiation, betel or areca nut, tobacco, and alcohol.^4,5 Additionally, human papilloma virus (HPV) infection forms a major etiological factor for oral cancer. The significance of this etiological factor can be ascertained from the fact that the prevalence of HPV among OPC increased from 16.3% in 1989 to 72.7% during 2000–2004.⁶ Currently, approximately 63% of all OPCs are attributable to HPV and may be preventable.^7,8 Thus, an awareness about HPV-related OPC can facilitate the reduction in the incidence of these cancers.

OPC is associated with high mortality. The primary reason for this is the silent presentation and late diagnosis of most patients.⁹ Thus, diagnosis of OPC in the early stages could decrease the mortality and morbidity associated with the condition. The oral cavity is easily accessible for clinical examination, especially for dentists, who can form the frontline for the prevention of oral cancer. Thus, increasing awareness and knowledge among dental professionals and patients could improve survival among patients with oral cancer.

Several HPV-related malignancies caused due to HPV 16 and 18 such as oral and cervical cancer can be prevented through HPV vaccination.¹⁰ Although the HPV vaccine is licensed for both females and males between 9 and 26 years of age, it is recommended in 11- and 12-year-old adolescents.¹⁰ Although it is not yet approved for preventing HPV-related OPCs, molecular and epidemiological data support a contributory role for HPV in OPC, and research is being carried out to investigate the efficacy of HPV vaccines for preventing OPCs.¹¹ It is therefore vital to target immunizable young adult college-going girls and boys, as both are part of the infection chain and at risk for HPV infection as they are growing adults with independent lifestyles but have a choice to undergo vaccination with the consent from parents and are within the age group of successful vaccination outcome.

HPV is a sexually transmitted infection. Thus, identifying the comfort of the healthcare professional to discuss these etiologies with their patients and the gaps in their knowledge regarding HPV assists in detecting early cases.

Although several studies have investigated the awareness of dentists regarding HPV vaccines, most of these studies have been limited to a single country. Thus, the present study attempted to compare the knowledge regarding HPV, its association with OPC, and HPV vaccine among students from different countries, years of the undergraduate program, and gender among dental undergraduate students from six countries, namely India, Pakistan, Saudi Arabia, Egypt, UAE, and Sudan.

Materials and Methods

Study Participants

The present cross-sectional study was conducted among 1500 dental students from six countries through Google survey forms from 5 July 2021 to 5 August 2021 after obtaining Dar al Uloom University ethical clearance. The study was conducted according to the guidelines of the Declaration of Helsinki and approved by the Institutional Review Board of College of Dentistry, Dar Al Uloom University, Riyadh, KSA (COD/IRB/2020/22). Students from the third year onwards of undergraduate dental education from Egypt, India, Pakistan, Saudi Arabia, UAE, and Sudan were included in the study. Students from any other country or those not in dental undergraduate training were excluded from the study. Only these countries were included as we could get permission for the concerned academic institutions through our known contacts at respective nations to circulate the survey among their students. The survey form was provided to the students through faculty working in the academic institutions of these countries. The nature of the study was described to every subject before they participate in the survey. The response of the participants was maintained confidential, and their consent was obtained electronically by their willingness to participate in this survey by answering all the questions.

Among 1500 dental students approached, only 886 responded within the stipulated time. The sample size was selected as per reference article and taking into account the number of students in each university fitting our inclusion criteria from six different nations. Considering the proportion of 0.641 (64.1%) from the pilot study, with relative precision of 5% and 95% confidence level, the calculated sample size came up to 864. The formula for calculating the sample size is as follows:

where P = expected proportion, 1- α/2 = desired confidence level, and ε = relative precision.

Data Collection

A Google survey form was created using survey items adopted from the studies by Sallam et al and Daley et al^12,13 Prior to the data collection, the questions were pretested among a group of 15 professionals to ensure the level of validity and degree of repeatability. The Google survey form was circulated by the faculty working in the academic institutions of each of the six countries through email and phone numbers. The survey took approximately 5–10 min to answer all the questions.

The survey form comprised 27 items divided into four sections (Figure 1). The first section comprised questions determining the demographics of the group, including age, sex, nationality, marital status, current level of education, and history of smoking. The second section attempted to determine the knowledge of oral cancer among the dental students and was termed as the knowledge-based questionnaire. The third section ascertained the awareness of HPV among participants and was termed as the awareness-based questionnaire. The fourth section comprised questions ascertaining the comfort of the practitioners to disseminate HPV information among patients and was termed as the attitude-based questionnaire.

Figure 1 Original survey that was circulated.

The aim of the study is to compare the awareness, knowledge, and perception about HPV and OPC among students from different countries, years of the undergraduate program, and gender.

Statistical Analysis

The data were collected and organized in MS-Excel. Statistical analysis was conducted using SPSS v 21 (IBM, Chicago, IL, USA). The demographic and survey data were collected as per frequency and percentage. Chi-square test was used to evaluate the correlation between the demographic characteristics of students and their knowledge regarding HPV and oral cancer. P < 0.05 was considered statistically significant.

Results

The demographic characteristics of patients are presented in Table 1. Of the 886 participants, a majority were females (73.1%). Most participants were from India (29.3%), followed by Saudi Arabia (21.8%).

Table 1 Demographic Characteristics of Participants

Tables 2 and 3 present the comparison of knowledge between on HPV and its relationship with OPC in males and females. The awareness of HPV and its association with OPC was higher in males than in females, and this difference was statistically significant (P < 0.05). On the other hand, females exhibited better knowledge and perception on HPV vaccine than males, and this difference was statistically significant (P < 0.05). Females exhibited a more positive attitude and comfort regarding the vaccine and discussing the same with patients than males, and this difference was statistically significant (P < 0.001).

Table 2 Association of Gender- with Attitude-Based Questionnaires

Table 3 Comparison of Knowledge Between Males and Females

Tables 4 and 5 present the comparison of knowledge on HPV and its relationship with OPC among students in different undergraduate years. Third- and fourth-year students exhibited better awareness of HPV and its association with OPC than other year students, and this difference was statistically significant (P < 0.05). The third-year and internship students exhibited a more positive attitude and comfort regarding the vaccine and discussing the same with patients than the other educational-level students, and this difference was statistically significant (P < 0.001).

Table 4 Association of Education with Awareness-Based Questionnaires

Table 5 Comparison of Knowledge Between Students from Different Undergraduate Years

Tables 6–8 present the comparison of knowledge on HPV and its relationship with OPC among students from different countries. Majority of Indian students exhibited better knowledge and awareness of HPV and its association with OPC than other year students, and this difference was statistically significant (P < 0.05). The Indian students exhibited better knowledge about HPV than other students from other countries, and this difference was statistically significant (P < 0.001). Indian students exhibited a more positive attitude and comfort regarding the vaccine and discussing the same with patients than students from other countries, and this difference was statistically significant (P < 0.001).

Table 6 Association of Country with Awareness-Based Questionnaires

Table 7 Association of Country with Attitude-Based Questionnaires

Table 8 Comparison of Knowledge Between Students from Different Countries

For the knowledge-based questions like Q9, Q14 where the answers could be multiple from the options, in these questions we tried to classify the students who have opted for more than 2 options to be having good knowledge (Table 8).

For Q 15 “The spread of HPV is by?”, all the respondents who opted “through sexual contact” and for Q 16 “Most HPV infections resolve within a short time”, all the respondents who opted for option “No”, and for Q 19 “Who are eligible to take HPV vaccine?”, all the respondents who opted for “ladies and gents below 30 years” are classified as having good knowledge as they opted for the correct answers (Figure 1).

Figure 2 illustrates the varying reasons for patients not getting vaccinated. Of the various reasons, lack of knowledge of vaccine is the most common reason for not getting vaccinated.

Figure 2 Reasons for unwillingness to get vaccinated.

Discussion

The incidence of HPV-associated OPC is increasing. Thus, awareness among healthcare professionals, especially dentists is required for the early diagnosis of this condition to reduce the associated mortality and morbidity. Thus, the present study evaluated the knowledge, attitude, and awareness of human papilloma virus and its association with oral lesions among dental undergraduate students in different nations.

The present study exhibited that males had better knowledge regarding HPV and its association with OPC, and this difference was statistically significant (P < 0.05). This finding differs from that of Reimer et al and Presto et al,^14,15 who exhibited better knowledge among females. This difference may be because of the smaller sample size for males (n = 238) in the present study as compared with females (n = 648). On the other hand, females exhibited better knowledge about HPV vaccines than males, and this difference was statistically significant (P < 0.05). HPV is also responsible for cervical cancer. Cervical cancer is the third most diagnosed cancer globally and the fourth leading cause of cancer-related mortality in women.¹⁶ This cancer is preventable, and the HPV vaccine is recommended to reduce its risk. Thus, women are more aware about the vaccine. This could also explain their increased comfort level to discuss this with patients. Additionally, female students were more comfortable discussing personal health and HPV vaccines with their patients than their male counterparts, and this difference was statistically significant (p < 0.05) (Table 2). This may be because females are more emotional than males, making them more at ease with discussing personal health with their patients.

The third-year dental students exhibited better knowledge about HPV than other year students, and this difference was statistically significant (P < 0.001). Additionally, students in internship also exhibited better knowledge, awareness, and attitude than the other year students. In India, third-year students have clinical subjects such as General Medicine in their curriculum. Thus, topics on HPV and its significance may be introduced. Additionally, students in their internships would have additional practical experience with patients. This would explain their better knowledge and awareness regarding HPV. Oral microbiology is an important component in the curriculum of dentistry. Certain microorganisms including HPV dictate special focus in dentistry not only in relation to cancer but other manifestations too.

The present study exhibited that dental practitioners were able to identify the risk factors associated with oral cancer. This finding was concurrent with that of Sallam et al and Lorenzo-Pouso et al.^12,17 Most dental practitioners exhibited discomfort in discussing the HPV correlation with oral cancer. This reluctance might be related to sociocultural and religious stigmas towards discussing sexually transmitted infections in these countries. It is recorded in the past that high increase in HPV-dependent OPC occurs in the United States, and other European countries and the frequency of HPV-infected OPC vary depending on geographical distribution and religious practices.^18–20 HPV is regarded to be a risk factor for the development of anogenital malignancies and cervical cancers, and HPV vaccines could help in the preventing the same.²⁰

This finding was concurrent with that of Sallam et al and Daley et al.^12,13 Additionally, dentists have never been accustomed to a vaccination recommendation as the nature of their work does not include this responsibility. This may be an additional reason for the discomfort among participants.^17,18 An additional reason for the discomfort may be the lack of professional guidelines for recommending the HPV vaccine as a primary prevention measure for OPC.²⁰

In the present study, Indian students exhibited better knowledge, awareness, and attitude about HPV than other students from other countries, and this difference was statistically significant (P < 0.001). India has the highest number of oral cancers globally, with approximately 1% of the population exhibiting oral premalignant lesions.²¹ Thus, Indian dental students have higher clinical exposure to OPC. Moreover, the gynecologists and general hospitals usually exhibit the advertisement boards about the HPV vaccine availability and their price in India. Therefore, they are better aware of the implications of HPV in oral cancer and cervical cancer. Further, the participants were not having information about the availability of HPV vaccine in their city or surrounding hospitals in the Middle East and African countries.

Most participants expressed a desire to participate in any professional training or continuous dental education program to achieve better knowledge and understanding about HPV and its association with OPC. This could be achieved through continuing dental education programs such as workshops, awareness campaigns, and training sessions. In the present study, of the various reasons, lack of knowledge of vaccine is the most common reason for not getting vaccinated, followed by lack of information about where to get the vaccine and lack of recommendation from the doctor. This underlines the necessity to imbibe knowledge regarding HPV and its association with OPV among medical and dental students.

The principal strength of the study is the multinational nature of the study allowing the generalization of the study findings. However, this study has certain constraints. The survey design always carries the risk of bias, with participants attempting to answer as per the researcher’s expectation. Additionally, the sample size was relatively small. Furthermore, most patients (73.1%) were female. This could also influence the results. Further studies with a larger sample size and evenly matched groups would strengthen the findings of this study. Several limitations in basic knowledge about HPV was noticed among participants in the clinical group, particularly related to unawareness of the vaccine availability.

Conclusion

Overall knowledge about HPV, the HPV vaccine, and HPV-related OPCs is deficient among students from this sample of undergraduate dental students. Those in their third and fourth clinical years were more knowledgeable about HPV.

More than half of them reported willingness to take the vaccine. With the increasing awareness regarding HPV-related oropharyngeal cancer, dentists must be able to advice and recommend patients regarding the risk factors and preventive measures associated with this condition. To enable this, dental colleges and organizations must provide additional information on HPV and the advances in vaccines to their students and members.