Abstract
Introduction
Oral health related quality of life is utilized in health services research to examine trends in oral health and population-based needs assessment.
Objective
To assess both the generic and orthodontic specific aspects of the Oral health-related quality of life of a University undergraduate population.
Methodology
This was a cross-sectional descriptive study carried out among 420 undergraduate students, aged 18-30years old, attending the University of Lagos, Nigeria. The data collection was carried out through oral interviews and self-administered questionnaires. Two Oral health related quality of life instruments were used (1) A generic scale: the Shortened version of the Oral Health Impact Profile (OHIP-14) and (2) A condition specific scale: the Psychosocial impact of dental aesthetics questionnaire (PIDAQ). Data analysis was carried out using the Statistical Package for Social Sciences (SPSS).
Results
With respect to the Oral Health Impact Profile (OHIP-14) scale, the overall mean score recorded by the students was 10.43+7.85. The physical pain subscale recorded the highest impact with 93.3%, while the least impact was recorded in the handicap subscale, with 29.9%. The Psychosocial Impact of Dental Aesthetics Questionnaire (PIDAQ) scales revealed significant gender differences, with the subscales of 'social impact', 'psychological impact' and 'aesthetic concern' recording low mean subscale values.
Conclusion
. The mean Oral Health Impact Profile (OHIP-14) score of the students (10.43 + 7.85) in this study reflects that the oral health status of most of the students did not significantly affect their Oral health-related quality of life. However, the physical pain domain was the most severely affected aspect of their Oral health-related quality of life. The Psychosocial Impact of Dental Aesthetics (PIDAQ) scale scores recorded significant gender differences.
Keywords: Oral Health Related Quality of Life, Undergraduate students, Young adults, Nigeria
Introduction
Quality of life is a vague and abstract concept with usages across many disciplines and in essence reflects an individual's experiences that influence one's satisfaction with life. It is an intangible entity and there has been much debate as to how to define it. However, there is a general consensus that it reflects physical, social and psychological functioning.1 According to the World Health Organization (WHO), it can be defined as " people’s perception of their position in life in the context of the culture and value systems in which they live and in relation to their goals, expectations, standards, and concerns".2 It is a multidimensional concept that can be investigated from different points of view, and health and medicine are closely connected with this concept.3
In response to the WHO definition of health as a complete state of physical, mental and social wellbeing and not just the absence of disease (WHO 1948),4 health service researchers have focused on health as a multidimensional construct. This concept of health status embraces the biopsychosocial model of health into which symptoms, physical functioning and emotional and social wellbeing are incorporated. Quality of life (QoL), or individuals' "perceptions of their position in life in the context of the culture and value systems in which they live, and in relation to their goals, expectations, standards and concerns” is now recognized as a valid parameter in nearly every area of physical and mental healthcare, including oral health. 5
Oral health related quality of life is defined as "a standard of health of the oral and related tissues which enables an individual to eat, speak and socialize without active disease, discomfort or embarrassment" 6or "the absence of negative impacts of oral conditions on social life and a sense of dentofacial self-confidence."7 The assessment of OHRQoL requires the use of a validated instrument. The purpose of an HRQL instrument is not just to measure the presence and severity of disease symptoms, but also to show the impact of the illness and/or the intervention on that individual and, in some cases, to study unmet patient needs.8
The measurement of HRQL is far from easy and there are a number of issues that continue to cause problems for researchers working in this field. The first problem is that there is little agreement on the definition of quality of life. As noted earlier, it is a somewhat intangible and there has been much debate on how to define it.9 Classification of health-related quality of life measures aids in the use of these instruments.
There are two main groups of instruments that may be used. Both approaches have their strengths and weaknesses, and there are advantages to using both instruments in a research study. These two instruments are the generic and condition -specific measures.8
Generic measures provide a summary of HRQL and may generate a single index measure or a health profile. Two main types exist.10 The first is the health profile, in which a separate score is generated for each domain for example the Oral health Impact Profile.11 In the other type are the health indices where scores generated from all answers are added up to give a single number or index. Conversely, specific measures focus on a particular condition, disease, population or problem, and are devised to measure patients' perceptions of the outcomes of health care interventions or to assess health needs. They may be divided into four groups, e.g. condition or disease-specific—eg focus on orthodontics; domain specific—focus on one domain, e.g. depression or anxiety; population specific—focus on one population group e.g. children; symptom specific—focus on one type of symptom, e.g. pain.10 A good example of a condition –specific measure is the Psychosocial Impact of Dental Aesthetics Scale (PIDAQ) scale12 and this has also been validated among Nigerians.13
A wide variety of OHRQoL studies have been carried out in Nigerian populations.13-19 However, majority of these studies have mainly been carried out in children and adolescent populations.14,15,17,18 In addition, majority of these studies were carried out using generic scales, and very few documented studies have been carried out with condition specific scales such as the PIDAQ.12 Thus, the aim of this study was to assess the OHRQoL of an adult population by using a combination of a generic oral health scale, the OHIP-14,11 and an orthodontic specific scale, the PIDAQ,12 It is hoped that the findings from this study would provide baseline data that would help in the planning of oral health care services for this university undergraduate population.
Methodology
Ethical approval for the study was obtained from the Health Research Ethics Committee (HREC) of the Lagos University Teaching Hospital, Idi-Araba, Lagos and permission to carry out the study was also obtained from the Students’ Affairs Office, of the University of Lagos. In addition, informed written consent was obtained from all students selected to participate in the study after the study had been fully explained to them.
This was a cross-sectional study involving undergraduate students of the University of Lagos aged 18-30 years, with no previous history of orthodontic treatment. A total of 420 undergraduate students of the University, from four randomly selected halls of residence (two male and two female halls) participated in the study.
Two instruments, previously validated in this environment,13,16 were used to assess the Oral Health-related quality of life of the students, namely a generic oral health scale: the shortened version of the Oral Health Impact Scale (OHIP-14)11 and a condition specific scale: the Psychosocial Impact of Dental Aesthetics Questionnaire (PIDAQ).12 Data on the OHIP-14 was collected through structured interviews. This was used to measure impacts of oral problems, capturing an overall measure of functional limitation, physical pain, psychological discomfort, physical disability, psychological disability, social disability, and handicap. Questions were scored on a five point scale (4 indicating very often; 3, fairly often; 2, occasionally; 1, hardly ever; and 0 never). The sum of individual item responses were added together to generate an overall OHIP-14 score, with possible values ranging from 0 to 56.
Data on the PIDAQ scales were obtained from the self-administered questionnaires. The PIDAQ is a 23-item psychometric instrument for assessment of orthodontic specific aspects of quality of life, expressed in four domains of: dental self-confidence (six items), social impact (eight items), psychological impact (six items) and esthetic concern (three items). A five-point Likert scale was used to rate how much dental aesthetics exerted a positive or negative impact, ranging from 0 to 4 (0 indicating not at all; 1, a little; 2, somewhat; 3, strongly; and 4 very strongly). An overall PIDAQ score for each domain, was obtained by summing all item scores within the domain.11
Statistical analysis
Statistical Analysis was carried out using the Statistical Package for Social Sciences software, (SPSS) version 19, Chicago III, SPSS Inc. The OHIP-14 was scored using the simple count method (OHIP-SC) and the sum OHIP-14. The OHIP SC was done by counting the number of items to which a student responded 'occasionally', 'fairly often', and 'often ' regarded as impacts and 'hardly ever' and 'never' regarded as no impact. On the other hand, the Sum OHIP involved summing the numeric response codes (0 for ' never', 1 for 'hardly ever', 2 for 'occasionally', 3 for 'fairly often' and 4 for 'very often' ) for all 14 items to produce a single summary score for an individual. The sum OHIP score of 14 or less is indicative of no impact while score of 15 or more is indicative of impact. 20 Descriptive statistics was used to describe the students' age and sex, as well as the scores obtained for the different domains in OHIP-14 and PIDAQ assessments. Chi-square tests and student’s t-tests were used to assess for gender difference in the OHIP-14 and PIDAQ scores, respectively. The level of significance was set at p<0.05.
Results
A total of 420 undergraduate students of the University of Lagos participated in the study, however 45 records were excluded from analysis due to multiple missing entries in their questionnaires. Thus, the response rate was 89.26% and the final study sample was made up of 375 subjects. The male students made up 53.3% (200), while the female students made up 46.7% (175) of the final study sample giving a male to female ratio of 1.14.
The mean age for the total study sample was 21.97+ 2.97years, while the mean age for the male students was 22.67 + 3.06 years, that for the females was 21.16 + 2.65years There was a statistically significant difference between the mean ages for the male and female students with the male students recording a significantly higher mean age, than the female students (t=4.890, p=0.000). Table 1 shows the age and gender distribution of the participants in the study.
Table 1 . Age and Gender distribution of the students.
| Age range (yrs) | Gender n (%) | Total (%) | Cumulative Percentage (%) | |
| Male | Female | |||
| 18-20 | 50 (26.7) | 76 (47.2) | 126 (37.2) | 36.2 |
| 21-23 | 69 (36.9) | 52 (32.3) | 121 (34.7) | 71.0 |
| 24-26 | 42 (22.5) | 25 (15.5) | 67 (19.3) | 90.2 |
| 27-30 | 26 (13.9) | 8 (5.0) | 34 (9.8) | 100.0 |
| Total | 187 (100 ) | 161 (100) | 348(100) | |
| Mean | 22.67+3.06 | 21.16 2.65 | 21.97 + 2.97 | |
| t=4.890, df= 346, p=0.000 (Student's t test) | ||||
The mean OHIP-14 score recorded for the students in this study was 10.43+7.85.Table 2, shows the different oral health-related impacts in relation to the various daily activities of the students, according to the seven subscales of the OHIP-14 index. The ‘physical pain’ subscale recorded the highest impact with 93.3%. Next to physical pain were psychological discomfort (variables v and vi), psychological disability (variables ix and x) and functional limitation (variables i and ii) in that order. Handicap dimension (variables xiii and xiv) recorded the least impact, with 29.9%.
Table 2 . Frequency distribution of reported impacts on the 14 activities of the OHIP –14 measure based on the 7 subscales.
| OHIP-14Subscale | Question/Daily Activity | Oral health-related Impacts | ||
| No impact n (%) | Impact n (%) | |||
| 1. | Functional limitation | i. Had problems pronouncing words. | 296(78.9) | 79(21.1) |
| ii. Had worsening sense of taste. | 313(83.5) | 62(16.5) Sum= 37.6% | ||
| 2. | Physical pain | iii. Had painful aching. | 175(46.7) | 200(53.3) |
| iv Uncomfortable to eat any food. | 225(60.0) | 150(40.0) Sum= 93.3% | ||
| 3. | Psychological Discomfort | v. Had been self-conscious. | 210(56.0) | 165(44.0) |
| vi. Felt tense | 287(76.5) | 88(23.5) Sum=67.5% | ||
| 4. | Physical Disability | vii. Had an unsatisfactory diet? | 283(75.5) | 92(24.5) |
| viii. Had to interrupt meals | 302(80.5) | 73(19.5) Sum= 34.0% | ||
| 5. | Psychological Disability | ix. Found it difficult to relax | 317(84.5) | 58(15.5) |
| .x. Had been a bit embarrassed. | 292(77.9) | 83(22.1) Sum= 37.6% | ||
| 6. | Social Disability | xi. Had been irritable with other people. | 280(74.7) | 95(25.3) |
| xii. Had difficulty doing usual activities. | 344(91.7) | 31(8.3) Sum=33.6% | ||
| 7. | Handicap | xiii. Felt life in general was less satisfying. | 279(74.4) | 96(25.6) |
| xiv. Had been totally unable to function. | 359(95.7) | 16(4.3) Sum=29.9% | ||
Table 3 shows a comparison of the Oral Health Impact (OHIP-14) scores by gender. No statistically significant (x2; p>0.05) gender differences were recorded in relation to impacts on the daily activities as reflected by the different subscales of the OHIP-14 scale, in assessing the quality of life of the students.
Table 3 . Comparison of Oral Heath Impact Profile (OHIP-14) scores by gender.
| Subscale Domain | Question | Impact of QOL | Number (%) | X2 | P Value | |||
| Male | Female | |||||||
| 1. | Functional Limitation | i. Had a problem pronouncing words? | No Impact | 158(79.0) | 138(78.9) | 0.001 | 0.973 | |
| Impact | 42(21.0) | 37(21.1) | ||||||
| ii.Had worsening sense of taste | No Impact | 169(84.5) | 144(82.3) | 0.332 | 0.565 | |||
| Impact | 31(15.5) | 31(17.7) | ||||||
| 2. | Physical Pain | iii. Had a painful aching in the mouth | No Impact | 102(51.0) | 73(41.7) | 3.233 | 0.072 | |
| Impact | 98(49.0) | 102(58.3) | ||||||
| iv. Found it uncomfortable to eat food | No Impact | 123(61.5) | 102(58.3) | 0.402 | 0.526 | |||
| Impact | 77(38.5) | 73(41.7) | ||||||
| 3. | Psychological discomfort | v. Have you been self conscious? | No Impact | 105(52.5) | 105(60.0) | 2.131 | 0.144 | |
| Impact | 95(47.5) | 70(40.0) | ||||||
| vi. Felt tense? | No Impact | 151(75.5) | 136(77.7) | 0.255 | 0.614 | |||
| Impact | 49(24.5) | 39(22.3) | ||||||
| 4. | Physical Disability | vii. Had an unsatisfactory diet | No Impact | 156(78.0) | 127(78.6) | 1.486 | 0.223 | |
| Impact | 44(22.0) | 48(27.4) | ||||||
| viii. Had to interrupt meals? | No Impact | 164(82.0) | 138(78.9) | 0.588 | 0.443 | |||
| Impact | 36(18.0) | 37(21.1) | ||||||
| 5. | Psychological Disability | ix. Found it difficult to relax? | No Impact | 171(85.5) | 146(83.4) | 0.306 | 0.580 | |
| Impact | 29(14.5) | 29(16.6) | ||||||
| x. How been a bit embarrassed | No Impact | 151(75.5) | 141(80.6) | 1.393 | 0.288 | |||
| Impact | 49(24.5) | 34(19.4) | ||||||
| 6. | Social Disability | xi. Have been irritable with other people | No Impact | 157(78.5) | 128(70.3) | 3.329 | 0.068 | |
| Impact | 43(21.5) | 52(29.7) | ||||||
| xii. Had difficulty doing usual jobs | No Impact | 185(92.5) | 159(90.9) | 0.332 | 0.564 | |||
| Impact | 15(7.5) | 16(9.1) | ||||||
| 7. | Handicap | xiii. Felt like life in general is less satisfactory | No Impact | 151(75.5) | 128(73.1) | 0.272 | 0.602 | |
| Impact | 49(24.5) | 47(26.9) | ||||||
| xiv. Have been totally unable to function | No Impact | 190(95.0) | 169(96.6) | 0.564 | 0.453 | |||
| Impact | 10(5.0) | 6(3.4) | ||||||
| *p<0.05 | ||||||||
The mean scores recorded for the different subscales of the Psychosocial Impact of Dental Aesthetics Questionnaire (PIDAQ) are shown in Table 4. The mean value of 14.13+6.16 recorded for Dental self-confidence reflects an average value of dental self-confidence for the study population, as a score of 24 indicates the highest level of dental self-confidence, while 0 indicates the lowest level of dental self-confidence, attainable on the scale. On the contrary, for the three other subscales of 'social impact', 'psychological impact' and 'aesthetic concern', a score of 0 indicates that the appearance of the individual's dentition has had no negative 'social' or 'psychological' impact on the person's quality of life, neither has it been of aesthetic concern. Thus, the low mean scores obtained by the students in these three subscales may reflect a relatively ‘low’ social and psychological impact and aesthetic concern with respect to dental aesthetics, among the students.
Table 4 . Psychosocial impact of dental aesthetics questionnaire (PIDAQ) scores of the students.
| PIDAQ Subscale | Possible Range of Scores | Mean | (Sd) |
| Dental Self Confidence | 0- 24 | 14.13 | (6.16) |
| Social Impact | 0- 32 | 5.59 | (6.63) |
| Psychological Impact | 0- 24 | 8.22 | (5.66) |
| Aesthetic Concern | 0-12 | 1.63 | (2.77) |
A comparison of gender differences recorded for the different PIDAQ subscales are shown in Table 5. The female students exhibited significantly greater dental self-confidence than the males and also reported significantly lower social and psychological impacts due to their dental aesthetics, than the males. No statistically significant difference was observed between the male and female students, with respect to their aesthetic concern.
Table 5 . Gender distribution of the mean PIDAQ subscale scores of the students.
| Sex | Dental Self Confidence | Social Impact | Psychological Impact | Aesthetic Concern |
| Mean (SD) | Mean (SD) | Mean (SD) | Mean (SD) | |
| Male (200) | 13.46 (6.08) | 6.50 (7.06) | 9.01 (5.78) | 1.81 (2.89) |
| Female ( 175) | 14.89 (6.18) | 4.54 (5.94) | 7.32 (5.40) | 1.43 (2.62) |
| t value | -2.258 | 2.888 | 2.912 | 1.294 |
| p value | * 0.025 | * 0.004 | * 0.004 | 1.301 |
| *p<0.05, Student's t-test | ||||
Discussion
There is very little doubt that oral health is an integral part of general health and contributes to overall health-related quality of life. Quality of life issues are now at the forefront of public health policy.4Assessment of OHRQoL allows a shift from traditional medical/dental criteria to assessment and care that focus on a person's social and emotional experience and physical functioning in defining appropriate treatment goals and outcomes.21 Patients' subjective evaluation of the healthcare decision -making process is changing the dynamics of clinical practice and health outcomes monitoring and research. 6
The mean OHIP 14 score recorded for the students in this study was (10.43+7.85) and since a mean OHIP value of less than 14 is indicative of no impact, 20 it can be inferred that the oral health status of the students had a minimal impact on their quality of life. Similar findings have also been reported in related cross-sectional studies, in which the OHIP-14 was administered to Indian22 and Brazillian23 undergraduate university students. There are two important factors which are directly related to a low OHIP-14 score and these are: low frequency or degree of severity of oral problems and the inability of certain individuals to perceive such problems. 23 Considering the fact that the study participants were university students and thus well educated, the second consideration is less likely to be a major factor.
In this study, the highest impact recorded by the students on the OHIP-14 scale was for ‘painful aching in the mouth’ (53.3%), while the 'Physical pain' subscale also recorded the highest impact (93.3%). This was followed by the 'psychological discomfort' subscale, with many of the students reporting that they had ‘felt self-conscious’, because of problems with their mouth or teeth. Studies carried out among undergraduate university students in Brazil, 23 India24 and Pakistan25 also report that the psychological discomfort and physical pain subscales contributed the most impact to the OHRQoL of the students. Local studies carried out among Nigerian adolescents using the OHIP-14, have also reported that ‘painful aching’ was the item which recorded greatest impact in the quality of life of the adolescents.18,19 In this study, the painful aching complained of by the students could have been from toothache or periodontal problems. However, one of the limitations of the OHIP-14 is that it does not elicit the specific cause(s) of the impacts recorded which can be related to a wide variety of oral health conditions.26
The handicap subscale recorded the least impact on the quality of life of the students, closely followed by the social disability subscale. The low impact recorded on the handicap subscale, implies that the oral health status of the students 'did not make them feel that life in general was less satisfying' or make them ' totally unable to function'. Thus, although 67.5% of the students reported that their oral health status had caused them considerable psychological discomfort, they did not allow this to interfere significantly with their social relations, which may explain the low scores on the social disability and social handicap subscales. Similar findings have been reported in closely related studies 23,24 and in previous research in school children in Lagos.19 The absence of significant gender differences in all seven subscales of the OHIP -14, implies that there was no difference between the impacts of oral health on the daily activities of the male and female students. This finding may be as result of the similar educational level of both genders in the study. A similar finding was also observed in a study carried out among Brazilian undergraduate students.23 Thus, based on the OHIP-14 scale, gender may not be an important consideration in planning oral health services for this undergraduate student population.
However, gender comparisons of the PIDAQ subscale scores of the students, revealed that statistically significant gender differences were observed in the Dental self-confidence, Social impact and Psychological impact subscales, with the females recording a significantly higher level of dental self-confidence than the males. Dental self-confidence reflects the impact of dental aesthetics on the emotional state of the individual.12 In addition, the female students recorded a significantly lower, social and psychological impact of dental aesthetics than the male students. No significant gender difference was observed with respect to the aesthetic concern of the students. The gender differences observed in this study, indicate that the female students were more self-assured of their dental aesthetics, than the male students. Given that this is a young adult population, it may be argued that the male students who are most likely eager to seek the approval of the female students at this age, may be more worried about their dental aesthetics and how it is perceived by others, particularly members of the opposite sex; than the females. A similar study carried out in a Southwestern Nigerian University, reported no significant gender difference in the PIDAQ subscales of the participants.13 Other studies have also reported the absence of gender differences.12,27 However, some studies have reported that women are more critical of their perception of impacts related to dental aesthetics28,29 These findings may be as a result of the commonly reported greater concern about health in women than in men, as expressed by higher attention to health care and greater awareness of oral health impacts.29 A possible reason for the differences between the findings in this study and those with contrasting findings is the differences in age of the study populations, as many of these other studies were carried out in children and adolescent populations.
A comparison of the findings from using the OHIP-14 and the PIDAQ scales in assessing the OHRQoL of the students, shows marked dissimilarity in the gender differences recorded for both scales. While the OHIP-14 recorded no gender differences in the impacts of the oral health status of the students on their OHRQoL; marked gender differences were observed in the mean PIDAQ subscale scores of the students, in assessing the impact of dental aesthetics on their OHRQoL. These findings highlight the different gender sensitivities of both scales in assessing OHRQoL in young adults, which is most likely as a result of their generic and condition specific properties. However, a major similarity in the findings from both the OHIP-14 and PIDAQ scales, is the low social impact, the oral status and dental aesthetics of the students had on their oral health-related quality of life. Indeed, the findings from this study show that combining the use of a generic scale such as the OHIP-14 (which assesses the impact of oral health on daily activities) and a condition-specific scale such as the PIDAQ scale (which places greater emphasis on dental aesthetics); provides a well-rounded assessment of the OHRQoL of a young adult population.
This study also has some limitations based on the fact that all the data analyzed were self-reported by the students and the evaluation of health, based solely on self-reports. Therefore it is important that the data is interpreted with caution due to the possibility of information bias, as it is possible that socially desired and undesired acts may have been, respectively, over or under estimated, by the respondents. Thus, there is a need for further studies which would assess the oral health status of the students and relate this to their oral health related quality of life.
Conclusions
The mean OHIP-14 score of the students (10.43 + 7.85) in this study reflects that the oral health status of most of the students did not significantly affect their Oral health-related quality of life. However, the physical pain domain was the most severely affected aspect of their Oral health-related quality of life. The PIDAQ scale scores recorded significant gender differences, with the female students exhibiting significantly greater dental self –confidence and lower social and psychological impacts due to their dental aesthetics, than the male students.
Footnotes
Competing Interests: The authors have declared that no competing interests exist.
Grant support: None
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