C.M.H.H. van Houtem

A review and meta-analysis of the heritability of specific phobia subtypes and corresponding fears

Evidence from twin studies suggests that genetic factors contribute to the risk of developing a fear or a phobia. The aim of the present study was to review the current literature regarding twin studies describing the genetic basis of specific phobias and their corresponding fears. The analysis included five twin studies on fears and ten twin studies on specific phobias. Heritability estimates of fear subtypes and specific phobia subtypes both varied widely, even within the subtypes. A meta-analysis performed on the twin study results indicated that fears and specific phobias are moderately heritable. The highest mean heritability (±SEM) among fear subtypes was found for animal fear (45%±0.004), and among specific phobias for the blood-injury-injection phobia (33%±0.06). For most phenotypes, variance could be explained solely by additive genetic and unique environmental effects. Given the dearth of independent data on the heritability of specific phobias and fears, additional research is needed.

Is dental phobia a blood-injection-injury phobia?

Dental phobia is part of the Blood‐Injection‐Injury (B‐I‐I) phobia subtype of specific phobia within DSM‐IV‐TR. To investigate the conceptual validity of this classification, the purpose of the present study was to determine the co‐occurrence of dental phobia, typical dental (and B‐I‐I related) fears, vasovagal fainting, and avoidance of dental care.

The burden of disease of dental anxiety: generic and disease-specific quality of life in patients with and without extreme levels of dental anxiety.

The aim of this study was to compare disease-specific (oral health-related) quality of life (OHRQoL), assessed using the Oral Health Impact Profile-14 (OHIP-14), and generic (health-related) quality of life (HRQoL), assessed using the EuroQol5D (EQ-5D-5L), in patients with severe dental anxiety (who were visiting a centre for special care dentistry) with a control group from the general population. Seventy-six patients with severe dental anxiety [Dental Anxiety Scale (DAS) score ≥ 13] were matched, according to age, gender, and socio-economic status, to a control group of 76 participants in a larger epidemiological study on oral health in the Netherlands (n = 1,125). The Wilcoxon signed-rank test was used to compare levels of HRQoL and OHRQoL in both groups. The total OHIP score (indicating lower OHRQoL) was higher for the patient group (10th percentile = 30.5; 90th percentile = 46.0) than for the control group (10th percentile = 1.0; 90th percentile = 14.5). The patient group showed higher scores on all seven OHIP domains. Lower utility scores were found in patients with severe dental anxiety (HRQOL: 10th percentile = 0.7; 90th percentile = 0.9) relative to the control group (HRQOL: 10th percentile = 0.9; 90th percentile = 1.0). A disease burden of 74,000 disability-adjusted life years (DALYs) was calculated for the Netherlands. The findings of this study show differences between patients visiting a dental fear clinic and matched controls from the general population for both OHRQoL and HRQoL, indicating that having severe dental anxiety generates a significant burden of disease.

DSQ-13-jeugd: meetinstrument voor patiënt­tevredenheid van adolescenten, jongvolwassenen en ouders over tandartsbezoek

The Dental Satisfaction Questionnaire (DSQ) is a questionnaire consisting of 31 items assessing patient satisfaction with dental attendance. By means of factor analysis (principal component analysis), the number of items of the DSQ was reduced to 13, which together constitute the DSQ-13-youth. The first objective was to investigate the psychometric properties of the DSQ-13-youth; the second was to compare the satisfaction scores on the various dimensions between and within subgroups (23-year-olds, 17-year-olds and parents of 5-year-olds). The DSQ-13-youth has 4 domains measuring patient satisfaction with dental attendance. The internal consistency of those domains was high; the correlation between the domains low to moderate and the factor structure was highly congruent in the various subgroups. The differences in satisfaction scores between and within subgroups were small. The DSQ-13-youth is a reliable instrument to assess patient satisfaction with dental attendance among adolescents, young adults and the parents of young children in urban areas.

Ziektelast en kwaliteit van leven bij patiënten met en zonder extreme angst voor tandheelkundige behandelingen

In this study, a comparison was made between disease-specific (oral health-related) quality of life (OHQoL), measured with the OHIP-14 questionnaire, and generic (general health-related) quality of life (GHQoL), measured with the EQ5D-5L questionnaire, in patients with and without extreme dental treatment anxiety. A total of 76 patients who could not be treated due to extreme dental treatment anxiety were referred to a centre for special dentistry. These patients were matched, according to age, gender and socioeconomic status, with participants in an epidemiological study on oral health (n = 1125). Wilcoxon signed-rank tests were used on both groups to compare GHQoL and OHQoL. The total OHIP score was higher (representing a lower quality of life) in the patient group than in the control group. Anxiety patients scored higher on all 7 domains of the OHIP-14. With respect to general quality of life, patients with extreme treatment anxiety were found to report lower utility scores than the matched control group. With these results, a total disease burden of 74,000 disability-adjusted life years (DALYs) was calculated for extreme treatment anxiety in the Netherlands. The findings of this study reveal that having extreme dental treatment anxiety results in a significant disease burden in the Netherlands.In this study, a comparison was made between disease-specific (oral health-related) quality of life (OHQoL), measured with the OHIP-14 questionnaire, and generic (general health-related) quality of life (GHQoL), measured with the EQ5D-5L questionnaire, in patients with and without extreme dental treatment anxiety. A total of 76 patients who could not be treated due to extreme dental treatment anxiety were referred to a centre for special dentistry. These patients were matched, according to age, gender and socioeconomic status, with participants in an epidemiological study on oral health (n = 1125). Wilcoxon signed-rank tests were used on both groups to compare GHQoL and OHQoL. The total OHIP score was higher (representing a lower quality of life) in the patient group than in the control group. Anxiety patients scored higher on all 7 domains of the OHIP-14. With respect to general quality of life, patients with extreme treatment anxiety were found to report lower utility scores than the matched control group. With these results, a total disease burden of 74,000 disability-adjusted life years (DALYs) was calculated for extreme treatment anxiety in the Netherlands. The findings of this study reveal that having extreme dental treatment anxiety results in a significant disease burden in the Netherlands.

Cariës in Krachtwijken 2. Jongeren

In the Netherlands, no epidemiologic data on the oral health of cultural groups of children and adolescents living in deprived areas are available. The aim of the present study was to obtain an impression of the amount of caries experience among poorly educated groups of youngsters in deprived areas, in comparison with a reference group of poorly educated youngsters from the cities of Alphen aan den Rijn, Gouda, s-Hertogenbosch and Breda. 725 Poorly educated respondents participated in a clinical and sociological study. The reference group had the lowest caries experience and the youngsters living in deprived areas with a non-Dutch cultural affiliation had the largest amount of caries experience. The latter group had more untreated caries and in 20-year-olds, a relatively large number of teeth had been extracted. Despite the low numbers, the difference in average DMFS scores among 14- and 20-year-olds were statistically significant. In the Netherlands a cultural dichotomy in oral health appears to exist, independent of level of education, in which youngsters with a non-Dutch cultural background are at a disadvantage.In Nederland zijn tot op heden geen epidemiologische gegevens beschikbaar over de mondgezondheid van diverse culturele groepen jongeren die in achtergestelde wijken (Krachtwijken) wonen. De doelstelling van het onderzoek was een indruk te verkrijgen van de hoeveelheid carieservaring van de laagopgeleide jeugd uit Krachtwijken, in vergelijking met een referentiepopulatie van laagopgeleide jongeren uit Alphen aan den Rijn, Gouda, ’s-Hertogenbosch en Breda. Aan het onderzoek namen 725 laagopgeleide respondenten deel. De referentiepopulatie had de minste carieservaring en de jongeren uit Krachtwijken met een niet-Nederlandse culturele affiliatie de meeste. De laatstgenoemde groep had meer onbehandelde caries en bij de 20-jarigen waren bovendien relatief veel gebitselementen geextraheerd. Ondanks de kleine aantallen waren de verschillen in gemiddelde DMFS-scores statistisch significant bij de 14- en 20-jarigen. In de Nederlandse jeugd lijkt een culturele tweedeling in mondgezondheid te bestaan, onafhankelijk van opleidingsniveau, waarbij jongeren met een niet-Nederlandse culturele achtergrond in het nadeel zijn.

Cariës in Krachtwijken 1. Volwassenen

In Nederland zijn nauwelijks epidemiologische gegevens beschikbaar over de mondgezondheid van diverse culturele groepen in de volwassen bevolking die in achtergestelde wijken, zogenoemde ‘Krachtwijken’, wonen. De doelstelling van een onderzoek uitgevoerd in 2013 was een indruk te verkrijgen van de hoeveelheid carieservaring van laagopgeleide volwassen in Krachtwijken, in vergelijking met een referentiepopulatie in ’s-Hertogenbosch. In totaal 1.597 laagopgeleide respondenten namen deel aan het onderzoek. De referentiepopulatie had de meeste carieservaring, doordat zij relatief veel gerestaureerde vlakken (FS) hadden. De relatief lage carieservaring bij de respondenten in de Krachtwijken met een niet-Nederlandse culturele affiliatie werd grotendeels veroorzaakt door een lager aantal FS. De verschillen in gemiddelde FS-score waren statistisch significant in alle leeftijdscategorieen, behalve in de jongste. De strategie ‘extension for prevention’ voor de behandeling van caries in het blijvend gebit vormt mogelijk een verklaring voor het feit dat laagopgeleide volwassenen in ‘s-Hertogenbosch significant meer FS hadden dan zij met een niet-Nederlandse culturele affiliatie.