Knowledge deficit, attitude and behavior scales association to objective measures of sun exposure and sunburn in a Danish population based sample.

The objective of this study was to develop new scales measuring knowledge and attitude about UVR and sun related behavior, and to examine their association to sun related behavior objectively measured by personal dosimetry. During May-August 2013, 664 Danes wore a personal electronic UV-dosimeter for one week that measured their UVR exposure. Afterwards, they answered a questionnaire on sun-related items. We applied descriptive analysis, linear and logistic regression analysis to evaluate the associations between the questionnaire scales and objective UVR measures. Perceiving protection as routine and important were positively correlated with protective behavior. Knowledge deficit of UV and risk of melanoma, perceived benefits and importance of protection behavior was also correlated with use of protection. 'Knowledge deficit of UV and risk of melanoma and Perceived barrier towards sun avoidance between 12 and 15' were both associated with increased risk of sunburn. Attitude towards tan was associated to both outdoor time and exposure as well as use of protection, but not to sunburn. The results regarding Knowledge deficit of UV and risk of melanoma associated to UVR exposure and Perceived barrier towards sun avoidance between 12 and 15 emphasize the importance of awareness of melanoma risk and the priority of the skin cancer prevention advice. Shifting activities to outside the suns peak-hours could be an approach for structural and campaign preventive measures. Knowledge of items predicting exposure to UVR, use of protection and sunburn are important for planning of preventive interventions and melanoma research.

Effects of smartphone diaries and personal dosimeters on behavior in a randomized study of methods to document sunlight exposure.

Dosimeters and diaries have previously been used to evaluate sun-related behavior and UV exposure in local samples. However, wearing a dosimeter or filling in a diary may cause a behavioral change. The aim of this study was to examine possible confounding factors for a questionnaire validation study. We examined the effects of wearing dosimeters and filling out diaries, measurement period and recall effect on the sun-related behavior in Denmark in 2012. Our sample included 240 participants eligible by smartphone status and who took a vacation during weeks 26-32 in 2012, randomized by gender, age, education and skin type to six groups: 1) Control + diary, 2) Control, 3) 1-week dosimetry measurement, 4) 1-week dosimetry measurement + diary, 5) 3-week dosimetry measurement and 6) 1-week dosimetry measurement with 4 week delayed questionnaire. Correlation coefficients between reported outdoor time and registered outdoor time for groups 3-6 were 0.39, 0.45, 0.43 and 0.09, respectively. Group 6 was the only group not significantly correlated. Questionnaire reported outdoor exposure time was shorter in the dosimeter measurement groups (3-6) than in their respective controls. We showed that using a dosimeter or keeping a diary seems to increase attention towards the behavior examined and therefore may influence this behavior. Receiving the questionnaire with 4 week delay had a significant negative influence on correlation and recall of sunburn. When planning future UV behavior questionnaire validations, we suggest to use a 1-week interval for dosimetry measurements, no diary, and to minimize the time from end of measurement to filling out questionnaires.

Feasibility of smartphone diaries and personal dosimeters to quantitatively study exposure to ultraviolet radiation in a small national sample.

BACKGROUND: In 2007, a national skin cancer prevention campaign was launched to reduce the UV exposure of the Danish population. To improve campaign evaluation a questionnaire validation using UV-dosimeters was initiated. AIM: To show the feasibility of dosimeters for national representative studies and of smartphones as a data collection tool. MATERIALS AND METHODS: Participants were sent a dosimeter which they wore for 7 days, received a short diary questionnaire by text message each day and subsequently a longer questionnaire. Correlation between responses from questionnaire, smartphone diaries and dosimeters were examined. RESULTS: This study shows a 99.5% return rate (n = 205) of the dosimeters by ordinary mail and high response-rates for a smartphone questionnaire dairy. Correlation coefficients for outdoor-time reported through smartphones and dosimeters as average by week 0.62 (0.39-0.77), P < 0.001 (n = 40). Correlation coefficient for outdoor time estimated by questionnaire and dosimeters were 0.42 (0.11-0.64), P = 0.008. The subjective perception of the weather was the only covariate significantly influencing questionnaire estimates of actual outdoor exposure. We showed that dosimeter studies are feasible in national settings and that smartphones are a useful tool for monitoring and collecting UV behavior data. CONCLUSION: We found diary data reported on a daily basis through smartphones more strongly associated with actual outdoor time than questionnaire data. Our results demonstrate tools and possible considerations for executing a UV behavior questionnaire validation.

The effect of a school-based intervention on sunbed use in Danish pupils at continuation schools: a cluster-randomized controlled trial.

PURPOSE: To examine the effect of an educational intervention on sunbed use and intentions and attitudes toward sunbed use in 14- to 18-year-olds at continuation schools. METHODS: We randomized 33 continuation schools either to receive the educational intervention (n = 16) or to be controls (n = 17). Intervention schools received an e-magazine addressing the health risks of sunbed use. Information on behavior and intentions and attitudes toward sunbed use was gathered through self-administrated questionnaires before the intervention and at 6 months as a follow-up. The effect of the intervention was examined by multilevel linear regression and logistic regression. RESULTS: Sunbed use was significantly lower at follow-up among pupils at intervention schools versus pupils at control schools (girls: odds ratio .60, 95% confidence interval .42-.86; Boys: odds ratio .58, 95% confidence interval .35-.96). The intervention had no effect on intention to use sunbeds or attitudes toward sunbed use. The analyses revealed a significant impact of school on attitudes toward sunbed; the intraclass correlation coefficient was estimated to be 6.0% and 7.8% for girls and boys, respectively. CONCLUSIONS: The findings from the present study provide new evidence of a positive effect of an educational intervention on sunbed use among pupils aged 14-18 years at continuation schools.

Childhood body mass index and multiple sclerosis risk: a long-term cohort study.

BACKGROUND: Obesity in late adolescence has been associated with an increased risk of multiple sclerosis (MS); however, it is not known if body size in childhood is associated with MS risk. METHODS: Using a prospective design we examined whether body mass index (BMI) at ages 7-13 years was associated with MS risk among 302,043 individuals in the Copenhagen School Health Records Register (CSHRR). Linking the CSHRR with the Danish MS registry yielded 774 MS cases (501 girls, 273 boys). We used Cox proportional hazards models to estimate the hazard ratios (HRs) and 95% confidence intervals (CIs). RESULTS: Among girls, at each age 7-13 years, a one-unit increase in BMI z-score was associated with an increased risk of MS (HR(age 7)=1.20, 95% CI: 1.10-1.30; HR(age 13)=1.18, 95% CI: 1.08-1.28). Girls who were ≥95(th) percentile for BMI had a 1.61-1.95-fold increased risk of MS as compared to girls <85(th) percentile. The associations were attenuated in boys. The pooled HR for a one-unit increase in BMI z-score at age 7 years was 1.17 (95% CI: 1.09-1.26) and at age 13 years was 1.15 (95% CI: 1.07-1.24). CONCLUSION: Having a high BMI in early life is a risk factor for MS, but the mechanisms underlying the association remain to be elucidated.

Costs of illness for melanoma and nonmelanoma skin cancer in Denmark.

Incidences of melanoma and nonmelanoma skin cancer are high and increasing in many countries including Denmark. The diseases are highly preventable. We have estimated the healthcare costs of these cancers by comparing costs for cohorts of patients and matched controls in a national register-based study in Denmark. All incident patients with a diagnosis of melanoma, basal cell carcinoma, or squamous cell carcinoma in the period 2004-2008 were included. Four control individuals for each case were matched in terms of sex, age, and area of residence. Healthcare costs and productivity loss for patients and controls were estimated using Danish health and social registries 3 years before and 3 years after diagnosis. The healthcare costs of melanoma and nonmelanoma skin cancer were &OV0556;33.3 million in the 3-year period after diagnosis, with male patients inducing the highest costs for all three cancers and costs increasing with age. The diagnoses of basal cell carcinoma and melanoma had almost the same healthcare costs, but per patient average healthcare costs were higher for melanoma. The costs of melanoma and nonmelanoma skin cancers, which can be prevented by sensible sun habits, exceed the costs of the preventive measures of the Danish SunSmart campaign manifold. Costs of melanoma and nonmelanoma skin cancer are expected to increase in the future with populations aging in the western world. The analyses provide a strong argument for the societal rationale of skin cancer prevention in Denmark.

Sunburn in children and adolescents: associations with parents' behaviour and attitudes.

AIMS: Sunburn in childhood is a known risk factor for melanoma and non-melanoma skin cancer. Based on a theoretical model, we tested the hypothesis that parental attitudes and behaviour are related to the risk of sunburn in their children. METHODS: We analysed the association between behaviour in the sun and attitudes related to tanning among Danish parents and their children's risk for sunburn by logistic regression. Gender, educational level, and skin type of the responding parent were included as confounders and analyses were stratified for child age. RESULTS: In children aged 7-12 and 13-17 years, the risk of sunburn increased when parents had experienced sunburn themselves, and also for 13-17 year olds if parents had a very positive attitude towards tanned skin. We found no association between parental attitudes and behaviour and the risk of sunburn in children aged 0-6 years. CONCLUSIONS: Interventions to influence the attitudes and behaviour of parents could reduce their children's risk for excessive sun exposure and thereby their risk for melanoma and non-melanoma skin cancer. The results encourage preventive campaigns to focus on changing parental attitudes towards tanned skin and sun behaviour.

Determinants of sunbed use in a population of Danish adolescents.

In Denmark, melanoma is the most common type of cancer in individuals aged 15-34 years. Ultraviolet radiation from sunbeds is a risk factor for melanoma. Knowledge of the characteristics of sunbed users is important in the development and implementation of prevention strategies of sunbed use. The objective of this study was to examine sunbed use and its association with smoking, parental socioeconomic status (SES), friends' attitudes towards artificial tanning, and school environment among adolescents aged 14-18 years at continuation schools in Denmark. We conducted a survey among adolescents in Danish continuation schools in 2011. We examined sunbed use and its association with age, smoking, friends' attitudes towards artificial tanning, parental SES, and shared environment of the continuation school, using logistic regression. Within the past 12 months, 38% of the pupils had used a sunbed (70% girls and 28% boys). There was no difference in sunbed use according to age. Smoking and friends' positive attitudes towards, and higher use of sunbeds were associated with increased use of sunbeds. High SES of mothers' was associated with lower odds for sunbed use among girls. The association of school environment with sunbed use was modest compared with the other variables. Adolescents in continuation schools report a higher use of sunbeds than Danish adolescents as such. Educational interventions should be targeted at preteens, as sunbed use is common in 14-year-olds. Special educational tools are tested in the continuation school environment and may prove effective in this population.

A simple score for estimating the long-term risk of fracture in patients with multiple sclerosis.

OBJECTIVE: To derive a simple score for estimating the long-term risk of osteoporotic and hip fracture in individual patients with MS. METHODS: Using the UK General Practice Research Database linked to the National Hospital Registry (1997-2008), we identified patients with incident MS (n = 5,494). They were matched 1:6 by year of birth, sex, and practice with patients without MS (control subjects). Cox proportional hazards models were used to calculate the long-term risk of osteoporotic and hip fracture. We fitted the regression model with general and specific risk factors, and the final Cox model was converted into integer risk scores. RESULTS: In comparison with the FRAX calculator, our risk score contains several new risk factors that have been linked with fracture, which include MS, use of antidepressants, use of anticonvulsants, history of falling, and history of fatigue. We estimated the 5- and 10-year risks of osteoporotic and hip fracture in relation to the risk score. The C-statistic was moderate (0.67) for the prediction of osteoporotic fracture and excellent (0.89) for the prediction of hip fracture. CONCLUSION: This is the first clinical risk score for fracture risk estimation involving MS as a risk factor.

Short and long term variation in ultraviolet radiation and multiple sclerosis.

We examined the role of ultraviolet radiation (UVR) in persons diagnosed with multiple sclerosis (MS) in four different populations, Italians, Danish, White and African Americans. We tested whether variation in UVR as determined by seasons (short term variation) and solar cycles (long term variation) is related to MS birth month and to survival as measured by lifespan. Cases were selected from three Italian MS Case Registries (2,737); from the United States National Center for Health Statistics (56,020); and from the Danish Multiple Sclerosis registry (15,900). Chi-square tests were used to study the pattern of month of birth distribution in patients with MS comparing with general population data. T-tests were employed to study solar cycles association with lifespan. A surplus of births was observed in June for White Americans. A decrease of births in October and November, though not significant after multiple testing correction, was observed in the three populations. In White American with MS overall, males and females, we found that solar cycle is associated with lifespan. We found that season and solar cycles have some role in MS susceptibility and life duration. However, this is an exploratory analysis and further work is needed to discern the association.

Mobile phones and multiple sclerosis--a nationwide cohort study in Denmark.

We investigated the risk of, prognosis of and symptoms of multiple sclerosis (MS) among all Danish residents who owned a mobile phone subscription before 1996. Using the Danish Multiple Sclerosis Registry and Civil Registration System, study subjects were followed up for MS through 2004. Poisson models were used to calculate incidence rate ratios (IRR, age range: 18-64 years) and mortality rate ratios (MRR, age range: 18+) and to compare presenting symptoms among subscribers and all non-subscribers. A total of 405 971 subscription holders accrued four million years of follow up, with men accounting for 86% of the observation time. Among subscription holding men, the IRR of MS was close to unity, overall as well as 13+ years after first subscription (IRR 1.02, 95% CI: 0.48-2.16). Among women, the IRR was 3.43 (95% CI: 0.86-13.72) 13+ years after first subscription, however, based on only two cases. Presenting symptoms of MS differed between subscribers and non-subscribers (p = 0.03), with slightly increased risk of diplopia in both genders (IRR: 1.38, 95% CI: 1.02-1.86), an increased risk of fatigue among women (IRR: 3.02, 95% CI: 1.45-6.28), and of optic neuritis among men (IRR: 1.38, 95% CI: 1.03-1.86). Overall the MRR was close to one (MRR: 0.91, 95%CI 0.70-1.19) among MS-patients with a subscription and although we observed some increased MRR estimates among women, these were based on small numbers. In conclusion, we found little evidence for a pronounced association between mobile phone use and risk of MS or mortality rate among MS patients. Symptoms of MS differed between subscribers and nonsubscribers for symptoms previously suggested to be associated with mobile phone use. This deserves further attention, as does the increased long-term risk of MS among female subscribers, although small numbers and lack of consistency between genders prevent causal interpretation.

The risk of fracture in incident multiple sclerosis patients: the Danish National Health Registers.

BACKGROUND: Patients with multiple sclerosis (MS) may be at increased risk of fractures owing to osteoporosis and falling. OBJECTIVE: To evaluate the risk of fracture in incident MS patients drawn from a dedicated MS registry compared with population-based controls. METHODS: We conducted a population-based cohort study (1996-2007) utilising the Danish National Health Registers that were linked to the Danish MS Registry and the Danish MS Treatment Registry. Incident MS patients (2963 cases) were 1:6 matched by year of birth, gender, calendar time and region to persons without MS (controls). Cox proportional hazards models and logistic regression were used to estimate the risk of fracture in MS. Time-dependent adjustments were made for age, history of diseases and drug use. RESULTS: Compared with controls, patients with MS had no overall increased risk of fracture (adjusted hazard ratio (adj. HR): 1.0, 95% CI: 0.9-1.2). However, the risk of femur/hip fracture (adj. HR: 1.9, 95% CI: 1.1-3.4) was significantly increased compared to controls. As compared with unexposed patients, MS patients who had been exposed to a short course of methylprednisolone in the prior year had no significantly increased risk of osteoporotic fracture (adj. HR: 1.2, 95% CI: 0.5-2.9). Disabled MS patients with Expanded Disability Status Scale [EDSS] scores between 6 and 10, had a 2.6-fold increased risk of osteoporotic fracture (adjusted odds ratio (adj. OR): 2.6, 95% CI: 1.0-6.6) compared to patients with an EDSS score between 0 and 3. CONCLUSION: Patients with MS had a higher risk of femur/hip fracture than controls. Disability status is probably more important than glucocorticoid use in the aetiology of MS and osteoporotic fracture.

Incidence of fractures in patients with multiple sclerosis: the Danish National Health Registers.

BACKGROUND: Patients with multiple sclerosis (MS) are potentially at high risk of fracture due to falls and osteoporosis. OBJECTIVE: To estimate incidence rates of fractures in MS patients, stratified by fracture type, sex and age, and to compare these rates with controls. METHODS: The case population consisted of all patients with an accepted diagnosis of MS in the Danish MS Registry (1949-2007). Data were linked to the National Hospital Discharge Register (1977-2007). Patients with MS (n = 11,157) were 1:6 matched by year of birth, gender, calendar time and region to persons without MS (controls). Incidence rates of fracture were estimated as the number of fractures per 1000 person-years. Incidence rate ratios (IRRs) were calculated by dividing fracture rates in MS patients by fracture rates in controls. RESULTS: Among patients with MS, the incidence rate of any fracture yielded 22.8 per 1000 person-years. The IRR of any fracture between MS patients and controls was 1.40 (95% CI 1.33-1.46). In particular, IRRs of tibia fracture (3.36 [2.75-4.11]), femur fracture (6.66 [5.06-8.76]) and hip fracture (3.20 [2.83-3.62]) were elevated in MS patients versus controls. CONCLUSION: Fractures occurred more often in patients with MS, especially fractures of the tibia, hip and femur.

The risk of fracture in patients with multiple sclerosis: the UK general practice research database.

Patients with multiple sclerosis (MS) may be at an increased risk of fracture owing to a greater risk of falling and decreased bone mineral density when compared with the general population. This study was designed to estimate the relative and absolute risk of fracture in patients with MS. We conducted a population-based cohort study using data from the UK General Practice Research Database linked to the National Hospital Registry (1997-2008). Incident MS patients (n = 5565) were matched 1:6 by year of birth, sex, and practice with patients without MS (controls). Cox proportional-hazards models were used to derive adjusted hazard ratios (HRs) for fracture associated with MS. Time-dependent adjustments were made for age, comorbidity, and drug use. Absolute 5- and 10-year risks of fracture were estimated for MS patients as a function of age. Compared with controls, MS patients had an almost threefold increased risk of hip fracture [HR = 2.79, 95% confidence interval (CI) 1.83-4.26] and a risk of osteoporotic fracture that was increased 1.4-fold (HR = 1.35, 95% CI 1.13-1.62). Risk was greater in patients who had been prescribed oral/intravenous glucocorticoids (GCs; HR = 1.85, 95% CI 1.14-2.98) or antidepressants (HR = 1.79, 95% CI 1.37-2.35) in the previous 6 months. Absolute fracture risks were low in younger MS patients but became substantial when patients were older than 60 years of age. It is concluded that MS is associated with an increased risk of fracture. Fracture risk assessment may be indicated in patients with MS, especially those prescribed GCs or antidepressants.

Prevalence of multiple sclerosis in Denmark 1950--2005.

Multiple sclerosis is an inflammatory disease of the central nervous system of unknown aetiology. Its prevalence varies by ethnicity and place: persons of northern European descent are at increased risk while persons living at lower latitudes appear to be protected against the disease. The Danish Multiple Sclerosis Registry is a national registry established in 1956 after a population-based survey which receives information from numerous sources. It is considered to be more than 90% complete, with a validity of 94%. Using data from the Registry, we calculated prevalences per 100,000 inhabitants. The standardized prevalence of multiple sclerosis increased from 58.8 (95% confidence interval: 54.9-62.7) in 1950 to 154.5 per 100,000 (95% confidence interval: 148.8-160.2) in 2005, and the female to male ratio increased from 1.31 in 1950 to 2.02 in 2005. The increase in prevalence is due to both increased survival of multiple sclerosis patients and an increased incidence rate. The rise in prevalence in the past 50 years is probably due more to environmental factors than to genetic changes in the Danish population. Among women, environmental changes could include older age at first birth, use of oral contraceptives, or changes in sun behaviour and/or vitamin D status.

Further studies of the influence of apolipoprotein B alleles on glucose and lipid metabolism.

The effect of five genetic polymorphisms in the apolipoprotein B gene on parameters of lipid and glucose metabolism was assessed in 564 Danish mono- and dizygotic twins. Genotypes in apolipoprotein B T71I (ApaLI RFLP), A591V (AluI RFLP), L2712P (MvaI RFLP), R3611Q (MspI RFLP), and E4154K (EcoRI RFLP) were established using polymerase chain reaction and restriction enzyme digests. The effect of genotypes on lipid levels and on glucose, insulin, and HOMA (i.e., calculated parameters of beta-cell function and insulin resistance) was assessed by multivariate analyses of variance correcting for the effect of gender, age, glucose tolerance status, and body mass index. The effect of genotype on the risk of having impaired glucose metabolism was calculated by logistic regression analysis. Finally, linkage between allele sharing and physiological parameters was calculated by the new Haseman-Elston method. The allele frequencies of all five polymorphisms were similar to those previously reported for Caucasian populations. The L2711P (MvaI RFLP) polymorphism influenced LDL-cholesterol and LDL-to-HDL measures (p = 0.04 and 0.03, respectively), while the R3611Q (MspI RFLP) polymorphism had an effect on the insulin-to-glucose ratio (p = 0.04), and E4154K (EcoRI RFLP) influenced HOMAbeta (p = 0.04). Significant interactions were observed between genotype in T71I (ApaLI RFLP), A591V (AluI RFLP), R3611Q (MspI RFLP), and E4154K (EcoRI RFLP) and glucose tolerance on lipid-related parameters (0.03 < p < 0.004), and between genotype in L2712P (MvaI RFLP) and E4154K (EcoRI RFLP) and gender on lipid and glucose-related parameters (0.02 < p < 0.003). No genotypes were significantly associated with impaired glucose tolerance measured by logistic regression. Likewise, no effect of allele sharing in the five polymorphisms was seen in the dizygotic twins. The effect of the polymorphisms on lipid and glucose parameters could be mediated through linkage to genes with known effect on glucose metabolism or through free fatty acids exerting their effect on glucose metabolism.

LNA-enhanced detection of single nucleotide polymorphisms in the apolipoprotein E.

Genotyping of single nucleotide polymorphisms (SNPs) in large populations presents a great challenge, especially if the SNPs are embedded in GC-rich regions, such as the codon 112 SNP in the human apolipoprotein E (apoE). In the present study, we have used immobilized locked nucleic acid (LNA) capture probes combined with LNA-enhancer oligonucleotides to obtain efficient and specific interrogation of SNPs in the apoE codons 112 and 158, respectively. The results demonstrate the usefulness of LNA oligonucleotide capture probes combined with LNA enhancers in mismatch discrimination. The assay was applied to a panel of patient samples with simultaneous genotyping of the patients by DNA sequencing. The apoE genotyping assays for the codons 112 and 158 SNPs resulted in unambiguous results for all patient samples, concurring with those obtained by DNA sequencing.