Oral health-related quality of life in the LGBTIQ+ population: a cross-sectional study

Abstract The aim of this cross-sectional study was to investigate the associations between oral health-related quality of life (OHRQoL) and socioeconomic and demographic variables, suicidal ideation, self-perception of oral health, and experiences of dental care in the Brazilian adult LGBTIQ+ population. A sample of 464 participants completed self-administered online questionnaires and provided information for OHRQoL assessment, using the OHIP-14 instrument at three hierarchical levels of explanatory variables: LGBTIQ+ identities; socioeconomic and demographic data and existential suffering; and self-perception of oral health and experience of dental care. The collected data were fitted to hierarchical multiple logistic regression models, in which the associations between each independent variable with the OHIP-14 prevalence outcome were analyzed. The OHIP-14-prevalence index showed that 33.2% of the participants answered ‘frequently’ or ‘always’, and the highest frequencies were obtained for the psychological discomfort (27.8%), psychological disability (18.3%), and physical pain (17.5%) domains. According to the adjusted final model, LGBTIQ+ individuals who were more likely to have their OHRQoL affected were those who were indifferent (OR=3.21; 95% CI: 1.26-8.20), dissatisfied (OR=10.45; 95% CI: 3.86-28.26), or very dissatisfied (OR=53.93; 95% CI: 12.12-239.93) with their oral health status, and also those who had or have difficulty accessing dental treatment (OR=2.06; 95% CI: 1.24-3.41) (p<0.05). It may be concluded that the OHRQoL of the investigated Brazilian LGBTIQ+ population showed associations with individual aspects and with access to dental services.


Introduction
According to the World Health Organization (WHO), "LGBTIQ+ health refers to the physical, mental, and emotional well-being of people who identify as lesbian, gay, bisexual, transgender, intersex, or queer (LGBTIQ+).The plus sign represents the vast diversity of people in terms of sexual orientation, gender identity, expression, and sex characteristics (SOGIESC)." 1 Worldwide estimates show a mismatch between the growing scientific understanding of LGBTIQ+ health Declaration of Interests: The authors certify that they have no commercial or associative interest that represents a conflict of interest in connection with the manuscript.
needs and the evolution of health care for this population, given that a large part of these people still face pathologizing stigmas, discrimination, prejudice, and even violence that often persist within the health services they seek. 1,25][6] Together, these factors can lead to worse oral health-related quality of life (OHRQoL). 6he concept of OHRQoL is a multidimensional construct that encompasses functional, social, and emotional aspects and is related to the subjective assessment of the impact of oral health status on daily activities and on the well-being of individuals. 7,8everal instruments were developed to measure OHRQoL, among which, the oral health impact profile (OHIP) stands out for the fact that it evaluates several biopsychosocial domains. 7,82] Therefore, there is a need for studies with larger and more representative samples, as well as studies that investigate associations between socio-contextual variables and OHRQoL in this population, in order to fill these gaps in scientific production in Brazil.
Brazil is reported, even in the absence of accuracy associated with official data, as the most "LGBTIQ+phobic" country in the world, where it is estimated that an LGBTIQ+ is assaulted and killed, in that order, everyone and 27 hours. 13,14his context can lead to existential suffering and suicidal ideation in this population, affecting their quality of life. 15,16However, the implications of this aspect on the OHRQoL of this population are not known.
Therefore, the aim of this study was to investigate the associations between OHRQoL and socioeconomic and demographic variables, existential suffering, selfperception of oral health, and dental care experience in a sample of the adult LGBTIQ+ Brazilian population.

Methodology
This is a cross-sectional observational study, whose development was guided by the recommendations of the STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) initiative 17 and approved by the Research Ethics Committee of the Piracicaba Dental School (CAAE: 43945421.0.0000.5418).
The study was developed in Brazil and involved the application of self-administered questionnaires on an online environment (Google Forms ® ).
Study participants (adult LGBTIQ+ population with internet access) were recruited through five social networks (1.Instagram®: @saude.bucal.lgbtqiamais; 2. Facebook®: @saude.bucal.lgbtqia; 3. TikTok®: @saude.bucal.lgbtqia+;4. Twitter®: @saude.bucal.lgbtqia+; and 5. WhatsApp ®: participation in interaction groups with LGBTQIA+ themes).Content about oral health and quality of life of the LGBTIQ+ population was periodically published on the aforementioned social networks in order to stimulate curiosity about the subject and to encourage the participation of the adult LGBTIQ+ Brazilian population in the study.In all posts on social media, there was an invitation letter that carried a link and QR code for interested parties to have access to the data collection instrument.In the aforementioned invitation letter, an access link (https://forms.gle/qZkMjeignjhjNw6j9)and QR code were provided for the participant to join the study.It is worth noting that the data collection process (from April 2021 to October 2022) relied on the participants' reading and virtual knowledge of the informed consent form.Thus, before completing the data collection instruments, participants were informed about the estimated time (10 minutes) to answer the questionnaires and about the confidentiality and archiving of the data provided (all information collected was digitally archived in a virtual space, Google Drive®, highlighting the authors' commitment to maintaining the anonymity of all participants, deleting the data collected 10 years after the date of publication of this study), in addition to providing the main researcher's data (name, e-mail address, and telephone) to resolve any doubts.The data collection instruments were applied in "Google® Forms," which allows the participant to return or proceed with the questionnaire-filling process, and conclude it by submitting the duly answered questionnaires.The total number of questions was 25 and the response time was approximately 10 minutes.The usability and technical functionality of the electronic questionnaire had been tested before fielding the questionnaire with three people from the LGTBIQA+ population, asking whether they had encountered any difficulties using and completing the questionnaire.No difficulties were reported by the participants regarding the aforementioned aspects.The eligibility criteria were minimum age of 18 years, self-identification as LGBTIQ+, and access to the internet.
The main outcome of the study was the OHRQoL 7,8 of the LGBTIQ+ population, measured by the scores of the OHIP-14 questionnaire, which consists of 14 questions distributed across seven biopsychosocial domains. 7,8,14,18This instrument offers five response options for each question, using a Likert scale (0 = never; 1 = rarely; 2 = sometimes; 3 = fairly often; 4 = very often). 7,8,14,18,19An established summary score or indicator was used, that is, prevalence of impacts, which represent the percentage of people responding 'fairly often' or 'very often' to one or more questions of the OHIP.Higher values denote poorer OHRQoL. 18,191][22] According to that model, socioeconomic factors and barriers to access services are considered examples of general stressors that affect the mental health of LGBTIQ+ people.Distal minority stressors include sexuality, color/race/ethnicity, and gender identity, and they can be associated with objective experiences of discrimination, oppression, and aggression (distal stress processes).Lastly, proximal stress processes are related to subjective processes or internal experiences and include self-critical beliefs, expectations of rejection, internalized homophobia, among others. 20n the present study, the variables were adapted to the model as follows: Level 1: general stressors such as completed level of education (up to elementary, high school and/or technical, higher/college, and graduate), monthly family income in Brazilian m inimum wages (BMW), which was later converted to U.S. dollars for the statistical analysis (1BMW ≈US$ 261), and accessibility to dental treatment (Have you had or do you have difficulty accessing dental treatment, that is, going to the dentist?/ yes; no; I have never looked for and/ or been to the dentist). 23evel 2: distal stress processes -included gender identity (how do you identify yourself?cisgender or transgender), sexual orientation (regarding your sexual orientation, how do you identify yourself?homosexual; heterosexual; bisexual; pansexual; asexual; other sexual identity), age (in years), color/ race/ethnicity (white, brown, black, yellow/oriental/ Japanese, indigenous, other), and suicidal ideation (have you ever thought about, planned, or tried to commit suicide / take your own life?][26] Level 3: proximal stress processes -included the assessment of satisfaction with oral health status (regarding your teeth/mouth/oral health, what is your degree of satisfaction?very satisfied; satisfied; neither satisfied nor dissatisfied; dissatisfied; very dissatisfied) and self-perception of professional preparation to care for LGBTIQ+ patients (Do you believe that dentists are prepared to care for LGBTIQ+ patients?/ yes; no) 4,27 (Figure).
For all the questions mentioned above, there was the answer option "I prefer not to answer or I do not know the answer." The sample size of the study involved the calculation of effect size, using the EpiInfo TM software (version 7.2) 28 , and was based on parameters found in the collected data (rate of unexposed participants: 18%; minimum detectable odds ratio of 2.0 -information extracted from the outcome and the independent variable, in that order, "impact of OHRQoL" and "had or have difficulty accessing dental treatment").Following this analytical approach, with a significance level of 5% (α = 0.05) and test power of 80% (β = 0.2), the minimum sample size was 398 participants.
Statistical analysis began with the descriptive evaluation of the variables.The data were then adjusted by logistic regression models to analyze the associations of each independent variable with the outcome (impact of OHRQoL). 29Variables with p < 0.20 were studied in hierarchical multiple logistic regression models. 29The variables were inserted in the model according to hierarchical levels, that is, the group of variables that make up the first level was the first to be inserted in the multiple model, followed by the group of variables at the second and third levels.The statistically significant variables of a hierarchical level were kept in the model and were analyzed together with the subsequent level, maintaining only the variables with p ≤ 0.05 in each model.The quality of adjustments was assessed using the Akaike information criterion (AIC). 29Unadjusted and adjusted odds ratios were estimated using model coefficients, with the respective 95% confidence intervals.In addition, we evaluated associations of cisgender and transgender people who answered 'frequently' or 'always' to one or more items of the OHIP-14, together with some outcomes, in order to understand in more detail how gender identity can affect them.For this purpose, the chi-square and Fisher's exact tests were used.All these analyses were performed using the R ® statistical software. 30

Results
A total of 496 people participated in the study, of whom 32 (6.5%) were excluded 11 for being under 18 years of age and 21 for not fully completing the data collection instruments), thus totaling 464 LGBTIQ+ participants.
Most of the sample consisted of male (64.2%), cisgender (70.7%), and homosexual (55.4%) individuals (Table 1).The mean age of participants was approximately 30 years (standard deviation, SD = 10), 53.2% were white, 42.7 had finished high school, had a monthly family income of less than US$ 783 (48.3%), and only 38.6% never thought about, planned, or tried suicide.Less than half of the participants (46.1%) reported being satisfied or very satisfied with their oral health status (Table 1).
Regarding dental experience, 42.5% reported that they had difficulties accessing dental treatment and only 22.8% of the sample believed that dentists were prepared to care for LGBTIQ+ patients (Table 1).
As for the OHRQoL, 33.2% of the participants answered 'frequently' or 'always' to one or more OHIP-14 items.Regarding the impact for each domain,  it is important to highlight that "psychological discomfort (27.8%)," "psychological disability (18.3%)," and "physical pain (17.5%)" presented the highest frequencies (Table 2).Table 3 presents the exploratory analysis of the collected data, from which statistically significant associations were verified between the OHIP-14 prevalence indicator and the following independent variables of the study: "gender identity;" "age;" "highest level of education completed;" "household income;" "suicidal ideation;" "satisfaction with oral health status;" and "difficulty accessing dental treatment." In the case of gender identity, the values pointed to a greater impact on the OHRQoL of transgender people when compared to cisgender people, considering that 44.8% of transgender individuals answered 'frequently' or 'always' to one or more items of the OHIP-14 (prevalence), while for cisgender individuals, this frequency was nearly half (28.3%) (Table 3).
The level of education showed a relationship between lower educational levels and greater prevalence of the impact on OHRQoL.Thus, among those who answered 'frequently' or 'always' to one or more items of the OHIP-14 (prevalence), 57.1% had no schooling or 52.2% had completed elementary school (Table 3).
With regard to family income, the most vulnerable individuals in terms of OHRQoL were those in the poorest family settings.The frequency of impact among those with incomes below three BMW or US$ 783 (46.4%) was much higher than those who reported income above 10 BMW or US$ 2,610 (17.6%) (Table 3).
As for suicidal ideation, vulnerability was more intense among those who thought about and planned (48.0%) suicide and those who thought about, planned, and tried (47.2%) suicide.
With regard to oral health, the greatest impact on OHRQoL was verified among those who were very dissatisfied with their oral health status (90.6%) and who reported difficulty accessing dental treatment (52.8%) (Table 3).
Next, the hierarchical multiple logistic regression was used to evaluate the variables associated with the outcome OHIP-14-prevalence in the sample.According to the adjusted final model, LGBTIQ+ people who were more likely to feel the impact on their OHRQoL were those who were neither satisfied nor dissatisfied (OR=3.21;95%CI: 1.26-8.20),dissatisfied (OR = 10.45;95%CI: 3.86-28.26)or very dissatisfied (OR = 53.93;95%CI: 12.12-239.93)with their oral health status, and also those who had or have difficulty accessing dental treatment (OR = 2.06; 95%CI: 1.24-3.41)(p < 0.05) (Table 4).
Considering the findings in Table 3 regarding the greater prevalence of the impact on the OHRQoL of transgender people, some additional exploratory analyses were carried out.Table 5 shows the results of associations between cisgender and transgender people who answered 'frequently' or 'always' to one or more items of the OHIP-14 for the variables highest level of education completed, household income, suicidal ideation, satisfaction with oral health status, and difficulty accessing dental treatment.There was a significant association between gender identity and suicidal ideation, and satisfaction with oral health status and difficulty accessing dental treatment (p < 0.05) for people whose OHRQoL was affected (OHIP-14 prevalence measure).

Discussion
This study investigated the associations between the OHRQoL of a sample of LGBTIQ+ people and their sociodemographic data, suicidal ideation, self-perception of oral health, and history of dental treatment.To our knowledge, this is the first study to date in Brazil evaluating these aspects in a sample of LGBTIQ+ people, using a hierarchical model of analysis, thereby bringing new evidence for the oral health care of this population.The prevalence of OHIP-14 impacts in the sample was 33.2%, similar to that of a study conducted with this population in India. 9Likewise, psychological discomfort was the OHIP-14 domain with higher prevalence of reported impacts on LGBTIQ+ people in India and Malaysia. 9,10ompared to other populations, the prevalence of OHIP-14 impacts (OHIP-prevalence) in the present sample was higher than that verified in the general population in UK (16.%), 31 Canada (19.5%), 32 Australian men aged 70 years or older (10%), 33 and adults in São Leopoldo, Brazil. 34However, these percentages were lower than in populations with mental illness, generally greater than 50%, 25 among Australian people who inject drugs (48%), 35 and in rural riverine populations in Amazonas, Brazil (44.3 and 70.3). 36 was verified in the adjusted final model of regression that the OHRQoL of the individuals was statistically associated with satisfaction with the self-perceived oral health and difficulty accessing dental treatment.
Negative self-perception of oral health status, according to a systematic literature review, was associated with unfavorable social, economic, demographic, psychosocial, and behavioral factors, as well as with poor oral clinical status, and with OHIP-14 scores. 37Self-perception of oral health represents an important marker of OHRQoL for populations in many countries in that they affect people throughout their lives, whether due to pain and/or aesthetic issues and/or functional deviations of the stomatognathic system. 37According to a study developed among lesbian, gay, and bisexual U.S. adults, subjective measures of oral health were worse in this population compared to those of heterosexual adults. 5ifficult access to dental treatment could be associated with worse OHRQoL, as confirmed in previous studies. 9As for accessibility to dental treatment, there is evidence that the LGBTIQ+ population has less access to health services, including dental services, 1- 6,11 both in terms of quantity and quality, a fact that could be attributed to the professionals' lack of preparation and sensitivity to take care of this population, which reiterates inequities in their access to health services. 11,38]39 LGBTIQ+ is not a homogeneous population; therefore, health disparities exist between sexual orientation groups. 5Firstly, the frequency of thought and/or planned and/or tried suicide was 54.9% in cisgender persons and 82% in transgender individuals (Table 5).According to a recent systematic review and meta-analysis, transgender people are at a higher risk of experiencing suicidal thoughts during their lifetime compared to other gender minority populations, and almost half of the transgender individuals who have suicidal thoughts commit suicide. 16This information is very important for health teams and services.
In the present study, in the total sample, less than half of the participants reported being "very satisfied" or "satisfied" with their oral health status.However, when gender identity was taken into account (Table 5), there was a significant association between the transgender group and satisfaction with oral health status, compared to cisgender individuals.This finding was corroborated by the studies of Prates et al. (2021) 11 and Soares (2022). 6There are several factors that can contribute to these differences, including the greater need felt by transgender people to meet the social expectations about the female figure and what they accept as beautiful, and worse oral health status of transgender individuals. 6,11he same differences were observed in the difficulty in accessing dental services.]39 Thus, our results are in line with those of previous studies, 5,6 demonstrating that transgender persons ae among the most vulnerable groups in the LGBTIQ+ population. 39In order to overcome this problem, it is essential to include content and activities related to the LGBTIQ+ population in the training of future professionals in order to enable them to understand and address the specific needs and demands of these individuals for oral health care. 1,38,40his study has some limitations.The data were collected by self-administered questionnaires on an online environment, and that may have limited their completion by those with limited internet access or low computer literacy, thus compromising the sample size and representativeness of the population.Despite adequate effect size, the number of participants was affected by the range of some confidence intervals; therefore, we suggest the use of larger samples in future studies.No clinical exams were performed and, consequently, we were unable to know whether the self-perception of oral health in this population reflects clinical status from their mouths.Therefore, generalizability of the results of this study should be made with caution and future studies should seek to evaluate these aspects in other samples.
The strengths of our study were the sufficient sample size, which was much larger and representative than that of other studies carried out in Brazil (including 5 to 329 respondents). 6,11,12In addition, we used a validated instrument to investigate OHRQoL (OHIP-14), which allows us to compare our results with those of other studies that have adopted the same criterion.Moreover, the difficulty in investigating LGBTIQ+ individuals is noteworthy, considering that most of them do not reveal their sexual orientation easily because of social restrictions, and also that they have lower access to and use of dental services, especially transgender persons.
The findings of this study highlight a key element that could shape more effective public policies for oral health, thus having a greater impact on the well-being of the LGBTIQ+ population, which is underrepresented in studies, training, and dental care.

Conclusion
OHRQoL of the investigated Brazilian LGBTIQ+ population showed associations with self-perception of oral health and difficulties in accessing dental treatment.

Figure .
Figure.Conceptual model showing interconnected experiences that contribute to OHQOL of the LGBTIQ+ population (adapted fromMeyer, 2003).20 20

Table 2 .
OHRQoL of the LGBTIQ+ population according to OHIP-14 prevalence measure of impacts (responses rated as 'fairly often' or 'very often') and its domains (n = 464).

Table 3 .
Associations between the prevalence measure of the impact of OHRQoL (OHIP-14) on LGBTIQ+ people and the independent variables of the study (n = 464).

Table 4 .
Results of multiple regression analyses for the predictor variables associated with the OHIP-14-prevalence of LGBTIQ+ people (n = 464).

Table 5 .
Analysis of the associations between cisgender and transgender persons for the sample with impact on OHRQoL (OHIP-Prevalence) and highest completed level of education, household income, suicidal ideation, satisfaction with oral health status, and difficulty accessing dental treatment (n = 154).** Cases of non-response or 'don't know' were not considered for the application of the hypothesis test.