Risk factors for atopic dermatitis in New Zealand children at 3.5 years of age

BACKGROUND: The prevalence of atopic dermatitis (AD) is increasing in Western societies. The hygiene hypothesis proposes that this is due to reduced exposure to environmental allergens and infections during early life. OBJECTIVES: To examine factors associated with a diagnosis of AD at 3.5 years of age, especially those factors implicated by the hygiene hypothesis. METHODS: The Auckland Birthweight Collaborative study is a case-control study of risk factors for small for gestational age babies. Cases were born at term with birthweight < or = 10th centile; controls were appropriate for gestational age, with birthweight > 10th centile. The infants were assessed at birth, 1 year and 3.5 years of age. Data were collected by parental interview and examination of the child. AD was defined as the presence of an itchy rash in the past 12 months with three or more of the following: history of flexural involvement; history of generally dry skin; history of atopic disease in parents or siblings; and visible flexural dermatitis as per photographic protocol. Statistical analyses took into account the disproportionate sampling of the study population. RESULTS: Analysis was restricted to European subjects. Eight hundred and seventy-one children were enrolled at birth, 744 (85.4%) participated at 1 year, and 550 (63.2%) at 3.5 years. AD was diagnosed in 87 (15.8%) children seen at 3.5 years. The prevalence of AD did not differ by birthweight. AD at 3.5 years was associated with raised serum IgE > 200 kU L(-1), and wheezing, asthma, rash or eczema at 1 year. In multivariate analysis, adjusted for parental atopy and breastfeeding, AD at 3.5 years was associated with atopic disease in the parents: maternal atopy only, adjusted odds ratio (OR) 3.83, 95% confidence interval (CI) 1.20-12.23; paternal atopy only, adjusted OR 3.59, 95% CI 1.09-11.75; both parents atopic, adjusted OR 6.12, 95% CI 2.02-18.50. There was a higher risk of AD with longer duration of breastfeeding: < 6 months, adjusted OR 6.13, 95% CI 1.45-25.86; > or = 6 months, adjusted OR 9.70, 95% CI 2.47-38.15 compared with never breastfed. These findings remained significant after adjusting for environmental factors and a personal history of atopy. AD at 3.5 years was associated with owning a cat at 3.5 years (adjusted OR 0.45, 95% CI 0.21-0.97) but not with owning a dog at 3.5 years, pets at 1 year, nor with older siblings. Furthermore, AD at 3.5 years was not associated with gender, socioeconomic status, maternal smoking, parity, damp, mould, immunizations, body mass index or antibiotic use in first year of life. CONCLUSIONS: A personal and a parental history of atopic disease are risk factors for AD at 3.5 years. Duration of breastfeeding was associated with an increased risk of AD. No association was found with those factors implicated by the hygiene hypothesis. This study suggests that breastfeeding should not be recommended for the prevention of AD.     

A comparison between criteria for diagnosing atopic eczema in infants

BACKGROUND: Epidemiological studies have shown different estimates of the frequency of atopic eczema (AE) in children. This may be explained by several factors including variations in the definition of AE, study design, age of study group, and the possibility of a changed perception of atopic diseases. The role of IgE sensitization in AE is a matter of debate. OBJECTIVES: To determine the prevalence and cumulative incidence of AE in a group of unselected infants followed prospectively from birth to 18 months of age using different diagnostic criteria; to evaluate the agreement between criteria; and to describe the association between atopic heredity and postnatal sensitization, respectively, and the development of AE according to the different diagnostic criteria. METHODS: During a 1-year period a consecutive series of 1095 newborns and their parents were approached at the maternity ward at the Odense University Hospital, Denmark and a cohort of 562 newborns was established. Infants were examined and followed prospectively from birth and at 3, 6, 9, 12 and 18 months of age. AE was diagnosed using four different criteria, the Hanifin and Rajka criteria, the Schultz-Larsen criteria, the Danish Allergy Research Centre (DARC) criteria developed for this study and doctor-diagnosed visible eczema with typical morphology and atopic distribution. Additionally, the U.K. diagnostic criteria based on a questionnaire were used at 1 year of age. Agreement between the four criteria was analysed at each time point and over time, and agreement between the four criteria and the U.K. questionnaire criteria was analysed. RESULTS: The cumulative 1-year prevalence of AE using the Hanifin and Rajka criteria was 9.8% (95% confidence interval, CI 7-13%), for the Schultz-Larsen criteria it was 7.5% (95% CI 5-10%), for the DARC criteria 8.2% (95% CI 6-11%), for visible eczema 12.2% (95% CI 9-16%) and for the U.K. criteria 7.5% (95% CI 5-10%). The pairwise agreement between criteria showed good agreement, with rates varying between 93% and 97% and kappa scores between 0.6 and 0.8. Agreement analysis of diagnoses between the four criteria demonstrated that cumulative incidences showed better agreement than point prevalence values. CONCLUSIONS: Agreement between different criteria for diagnosing AE was acceptable, but the mild cases constituted a diagnostic problem, although they were in the minority. Repeated examinations gave better agreement between diagnostic criteria than just one examination. Atopic heredity was less predictive for AE than sensitization to common food and inhalant allergens in early childhood.     

Reliance on erythema scores may mask severe atopic dermatitis in black children compared with their white counterparts

BACKGROUND: The prevalence of atopic dermatitis (AD) has been shown to be higher in London-born black Caribbean children than in their white counterparts, but little is known about the severity of the disease. OBJECTIVES: To carry out a longitudinal survey to investigate potential risk factors for AD severity in children. We report our findings in relation to differences in disease severity between white and black children and the effect of inclusion and exclusion of erythema scores on this comparison. METHODS: The recruited children were identified by their general practitioners (GPs) as having presented with AD, and the U.K. diagnostic criteria for AD were used to verify the diagnosis. Interview and clinical examination of children took place up to four times, 6 months apart. Each time, the same observer assessed AD severity using the SCORAD (SCORe Atopic Dermatitis) index. Potential risk factors and confounders were evaluated with a five-page questionnaire. Non-parametric tests were used for statistical analysis and the study participant remained the unit of the analysis. RESULTS: In total, 137 children (82 urban and 55 rural) were recruited, and each seen up to four times. This gave 380 observations (69% of an expected 548). The urban population contained 42 (51%) white children, 26 (32%) black children and 14 (17%) from other races. The rural population was entirely white. The 14 children from other races were completely excluded from the statistical analysis. The black children were all born in the U.K. On crude analysis, children with black skin showed a non-significantly lower risk of severe disease when compared with white children (odds ratio, OR 0.84; 95% confidence interval, CI 0.4-1.76; P = 0.65), while a highly significantly increased risk was found after adjusting for erythema score (OR 5.93; 95% CI 1.94-18.12; P = 0.002). The difference remained significant even after controlling for other potential confounders. CONCLUSIONS: Black children with AD are about six times more at risk of having severe AD than their white counterparts. GPs and dermatologists should note that erythema can be a misleading indicator of severity in black children. Difficulties of assessment due to skin pigmentation might mean that severe cases are not being detected and appropriately treated.     

Prevalence and risk factors for atopic dermatitis in preschool children

BACKGROUND: Atopic dermatitis (AD) is a common condition in infancy which usually disappears by 3 years of age in a significant proportion of children. The prognosis is mostly determined by severity and presence of atopic sensitization. OBJECTIVES: To investigate prevalence of AD, comorbidities and risk factors in a population of preschool children aged 3-5 years. METHODS: Children in kindergartens were evaluated. The International Study of Asthma and Allergies in Childhood written questionnaire (WQ) was used, with additional questions on risk factors. Atopy was investigated by skin prick tests. RESULTS: One thousand, four hundred and two valid WQs (92% response rate) were returned for evaluation. The prevalence of AD symptoms in the last 12 months in the whole population was 18.1% (254 cases). Seventy-two per cent of these children presented AD-specific localizations. The prevalence of eczema as a doctor's diagnosis in the total population was 15.4%. Positive atopic sensitization was present in 18.6% of the total and in 32.2% of the AD study population, respectively. Multiple sensitivities were observed in 58.2% of sensitized children. The prevalence of sensitization demonstrated that the most common sensitizing allergens in children with AD were mites and grass pollen. Rhinitis symptoms and wheezing were present in 32.2% and 24.2%, respectively, of children with AD. Allergic sensitization to egg, cat, grass pollen and mites, as well as the presence of symptoms of rhinitis, and a positive family history of atopy were all significant risk factors for AD. CONCLUSIONS: The study demonstrates a high prevalence of AD and a close relationship with rhinitis symptoms. Significant risk factors for AD were sensitization to food or inhalant allergens as well as parental history of atopy.     

Effect of Mycobacterium vaccae on atopic dermatitis in children of different ages

BACKGROUND: Exposure to environmental microorganisms is associated with variations in the prevalence and severity of atopic diseases. We have previously shown that administration of a Mycobacterium vaccae suspension significantly reduced the severity of atopic dermatitis (AD) in children aged 5-18 years. OBJECTIVES: This study aimed to extend these observations to younger children. METHODS: Fifty-six children aged 2-6 years with moderate to severe AD were enrolled in a randomized, double-blind, placebo-controlled trial and given one intradermal injection of either killed M. vaccae suspension or buffer solution (placebo). Skin surface area affected and dermatitis severity score were assessed before and 1, 3 and 6 months after treatment. RESULTS: Although a 38-54% reduction in surface area affected by dermatitis was noted at all time points after M. vaccae administration (P = 0.005), this improvement was not significantly different from that observed in the placebo group. Meta-analysis of this and our previous cohort (97 children aged 2-18 years) showed that M. vaccae was associated with a significant improvement in clinical severity at all ages, whereas within the placebo group, younger but not older children showed a similar improvement. CONCLUSIONS: Despite a reduction in clinical severity associated with M. vaccae at all ages, no benefit could be found after administering M. vaccae to children with AD aged 2-6 years when compared with placebo. M. vaccae may offer greater benefit in children over 5 years old, whose AD appears less likely to regress spontaneously.     

Prevalence of atopic dermatitis, asthma, allergic rhinitis, and hand and contact dermatitis in adolescents. The Odense Adolescence Cohort Study on Atopic Diseases and Dermatitis

BACKGROUND: Atopic diseases are common in children and adolescents. However, epidemiological knowledge is sparse for hand eczema and allergic contact dermatitis in this age group. Furthermore, no population-based studies have evaluated the prevalence of atopic diseases and hand and contact dermatitis in the same group of adolescents. OBJECTIVES: To assess prevalence measures of atopic dermatitis (AD), asthma, allergic rhinitis and hand and contact dermatitis in adolescents in Odense municipality, Denmark. METHODS: The study was carried out as a cross-sectional study among 1501 eighth grade school children (age 12-16 years) and included questionnaire, interview, clinical examination and patch testing. RESULTS: The lifetime prevalence of AD was 21.3% (girls 25.7% vs. boys 17.0%, P < 0.001) using predefined questionnaire criteria. The 1-year period prevalence of AD was 6.7% and the point prevalence 3.6% (Hanifin and Rajka criteria). In the interview the lifetime prevalence of inhalant allergy was estimated as 17.7% (6.9% allergic asthma, 15.7% allergic rhinitis). The lifetime prevalence of hand eczema based on the questionnaire was 9.2%, the 1-year period prevalence was 7.3% and the point prevalence 3.2%, with a significant predominance in girls. A significant association was found both between AD and inhalant allergy, and between AD and hand eczema using lifetime prevalence measures. The point prevalence of contact allergy was 15.2% (girls 19.4% vs. boys 10.3%, P < 0.001), and present or past allergic contact dermatitis was found in 7.2% (girls 11.3% vs. boys 2.5%). Contact allergy was most common to nickel (8.6%) and fragrance mix (1.8%). CONCLUSIONS: High prevalence figures were found for atopic diseases, hand eczema and allergic contact dermatitis, and the diseases were closely associated. A considerable number of adolescents still suffers from AD, and a considerable sex difference was noted for hand eczema and allergic contact dermatitis. Nickel allergy and perfume allergy were the major contact allergies. In the future this cohort of eighth grade school children will be followed up with regard to the course and development of atopic diseases, hand eczema and contact dermatitis.     

The cost of atopic dermatitis in the Netherlands: an international comparison

BACKGROUND: Only a few international studies have assessed the economic burden of atopic dermatitis (AD), and no costs-of-illness study for AD has been done for the Netherlands. OBJECTIVES: To estimate the incidence, prevalence and health-care costs of AD in the Netherlands and to put these in an international perspective. METHODS: We conducted a retrospective cohort study by using the data of an information system of general practitioners (GPs). To calculate the health-care costs at the primary care level we assessed medical resources utilization. We assessed the costs of patients with more severe AD from a retrospective study of patient files at the department of dermatology of a general hospital. We compared our results with costs-of-illness studies for other countries. RESULTS: The overall general population incidence and prevalence of AD were 0.8% and 2.3%, respectively. The incidence and prevalence were high among children until the age of 6 years, respectively, 3.1% and 11.3%, but decreased rapidly thereafter. The total mean health-care costs per patient were USD71. The most significant costs were due to visits to the GP (USD32) and medication, mostly corticosteroids (USD21). Young children were treated more often with emollients alone. Only 7.8% of patients were referred to a specialist. The mean costs for these patients were USD186. Costs-of-illness studies for Australia, Germany, the U.K., the U.S.A. and the Netherlands suggested that the costs associated with AD vary considerably across countries. Estimates of the costs-of-illness for AD ranged from USD71 in the Netherlands to USD2559 in Germany per patient due to variation in the study population (GP vs. hospital) and the number of cost components included. Studies that included costs due to the time spent on treatment had relatively high estimates. CONCLUSIONS: The prevalence and incidence of AD are high among young children. In general, the health-care costs for AD were low. Patients' out-of-pocket costs were relatively high.     

Clinical improvement and significant reduction of total serum IgE in patients suffering from severe atopic dermatitis treated with oral azathioprine

Atopic dermatitis (AD) is a common inflammatory skin disease: the incidence is increasing in many countries and treatment can be difficult. The aim of this retrospective case series was to examine the effect of oral azathioprine on the clinical severity and serum IgE levels in 38 patients with severe atopic dermatitis. The AD was well-controlled in nearly 80% (30/38). The maintenance dose required was in the range 25-200 mg per day. Four patients withdrew because of adverse affects, including one case of pancytopenia, and a further four ceased azathioprine after 4 months because of a lack of clinical improvement. Total serum IgE levels were measured before commencing azathioprine and after two years of treatment in 26 patients. IgE levels decreased in almost all patients and this was statistically significant (P = 0.012).     

Validation of the International Study of Asthma and Allergies in Children (ISAAC) and U.K. criteria for atopic eczema in Ethiopian children

BACKGROUND: Reliable diagnostic criteria for atopic eczema (AE) are essential in order to make international comparisons and to identify possible disease risk factors. Little is known about the prevalence of atopic eczema and validity of diagnostic criteria for AE in developing countries where English is not the first language. OBJECTIVES: We sought to determine the prevalence of AE in an area of urban and rural Ethiopia, and to compare the predictive values of different questionnaire and examination methods for diagnosing AE in this population. METHODS: We conducted a cross-sectional survey of 7915 children aged 1-5 years living in and around the town of Jimma in southwest Ethiopia. AE prevalence was assessed in two ways: (i) by using the International Study for Asthma and Allergies in Childhood (ISAAC) questionnaire, and (ii) using the U.K. refinement of Hanifin and Rajka's diagnostic criteria. All possible cases identified by screening questions and random samples of controls were then examined by an experienced local paediatrician, who acted as a reference standard to determine the predictive value of the criteria used to diagnose AE. RESULTS: The overall 1-year period prevalence of AE according to ISAAC and U.K. criteria was 4.4%[95% confidence interval (CI) 3.95-4.85] and 1.8% (95% CI 1.5-2.1), respectively. Corresponding point prevalence estimates (symptoms in the last week) were 1.8% for ISAAC and 1.3% for the U.K. criteria. The positive predictive values of the ISAAC and U.K. criteria questions for AE symptoms still reported to be present (in the last week) at the doctor's examination were 48.8% and 55.5%, respectively. Corresponding negative predictive values were 90.5% and 90.1%, respectively. The sign of visible flexural dermatitis (a component of the U.K. criteria) when used alone had positive and negative predictive values of 57% and 91%, respectively. CONCLUSIONS: Neither the ISAAC nor U.K. criteria performed especially well in predicting cases of AE in this survey. Possible reasons include problems with questionnaire translation, cultural conceptions of terminology, asking parents rather than the child about symptoms, the transient nature of AE signs, and differences in what a doctor perceives to constitute a typical case of AE. The results do not preclude the use of standardized diagnostic criteria alongside a doctor's examination in future surveys of Ethiopian children, and knowledge of the criteria's limited predictive value should help to interpret study findings that have employed such criteria. Consideration should be given to adopting the sign of visible flexural dermatitis as a standard for estimating the point prevalence of AE throughout the world because it is less susceptible to problems with translation and interpretation.     

The excess of atopic eczema in East Germany is related to the intrinsic type

BACKGROUND: Prevalence data for atopic eczema based on a dermatological examination have not so far been available for East and West Germany. Possible differences in the proportions of extrinsic and intrinsic types of eczema, and how far these could explain differences in the prevalence of eczema, need to be clarified. OBJECTIVES: To compare the prevalence of atopic eczema in pre-school children between different locations in East and West Germany, and over a period of 7 years, at three time points. Additionally, to determine the proportions of intrinsic and extrinsic types of eczema by taking skin prick test reactivity into account. METHODS: Repeated cross-sectional studies in 1991, 1994 and 1997 in 5-6-year-old pre-school children at five different locations in West Germany (n = 2075) and six in East Germany (n = 1926) were carried out. Individuals with eczema were identified by an examination performed by physicians of the Department of Dermatology. In addition, a skin prick test and a standardized questionnaire were used. RESULTS: The overall prevalence of atopic eczema in these children was 10.4%. At all three times of investigation (1991, 17.5% vs. 11.2%; 1994, 12.6% vs. 8.7%; 1997, 11.2% vs. 4.5%) and in the total group (12.9% vs. 8.2%), the prevalence was significantly higher in East than in West Germany. After controlling for influences of sex, parental history of atopic diseases, observer and socio-economic status in multiple logistic regression analyses, these differences remained significant for 1991, 1994 and for the overall group (odds ratio, OR 1.78, 95% confidence interval, CI 1. 43-2.21). Girls (OR 1.56, 95% CI 1.27-1.92) and children whose parents had a higher level of school education (OR 1.17, 95% CI 1. 00-1.37) were affected more frequently. Of all children, 26.6%, and of those with eczema, 41.9% exhibited at least one reaction in the prick test (OR 2.21, 95% CI 1.75-2.80; sensitization in eczema vs. no eczema). Whereas 50.4% of the children with eczema in West Germany were sensitized, only 36.5% of the diseased children in East Germany reacted positively in the prick test (OR 1.77, 95% CI 1.12-2. 79). CONCLUSIONS: These results are in accordance with findings regarding allergic sensitization and hay fever and might indicate that factors other than allergy are responsible for the higher prevalence of atopic eczema in East Germany.     

Efalizumab for severe refractory atopic eczema: retrospective study on 11 cases

Background Efalizumab is a recombinant humanized murine monoclonal antibody against CD11a, approved for the treatment of plaque psoriasis. However, recent reports suggest that it also may be effective in the treatment of severe atopic dermatitis (AD). Objective To evaluate the clinical effect of efalizumab in AD. Methods A systematic retrospective study of the medical files of patients treated with efalizumab for AD in Danish dermatology departments. Positive outcome was defined as improvement of the disease registered in the patient's file over a period exceeding 6 months. Results Two of eleven patients had a positive outcome. Nine patients stopped treatment due to progression of AD or lack of effect. Limitations Retrospective study. Conclusions Only a minority of patients with severe AD responded to efalizumab treatment in a standard dose.     

Patterns of care and referral in children with atopic dermatitis and concern for food allergy

Although many providers believe that up to 30% of atopic dermatitis (AD) is food induced, food challenge studies show that food-induced eczematous reactions are rare. When food allergy is suggested to cause AD, it often leads to allergy testing with a high false-positivity rate, in turn further focusing parents on food allergy. Study subjects were children less than 11 years old with AD and food allergy suspicion. Prior diagnoses, provider, and testing patterns were assessed by questionnaire given to the parents. Thirty-eight patients with AD were enrolled. Most subject's parents suspected food allergy induced AD. Initial skin diagnoses were made by pediatricians (79%) and family practitioners (18%) as eczema. Allergy was suggested by providers as cause for AD in 63% of the present study's patients. Seventy-nine percent had allergy testing. Greater than 90% of parents claimed their children had food allergy and food-induced AD. Sixty-six percent had positive food allergy tests and 37% had definite history of immediate IgE reactions to food. The majority of this population had allergy suggested as causative for eczema by their primary care provider and were subsequently evaluated by allergist and allergy testing. Consensus about the role of food allergy between the different providers of AD in children would result in more effective, efficient, and less costly health care.     

No significant increase within a 3-year interval in the prevalence of atopic dermatitis among schoolchildren in Baranya County, Hungary

BACKGROUND: The prevalence of atopic dermatitis (AD) in children has significantly increased worldwide in the past decades. Although it is well known that the number of AD patients has also been growing in Hungary, there are only a few published prevalence studies that allow international comparisons. OBJECTIVES: The aim of this study was to estimate the prevalence of AD among schoolchildren in Baranya County in 2005 and to compare the data with those from 2002. METHODS: The data from the 1454 children (771 girls, 683 boys) surveyed in 2002, and 1454 children (760 girls, 694 boys) surveyed in 2005, respectively, aged 7-14 years were analysed. The distinct populations of the 7- to 9-year-old age groups were separately compared in relation to their lifetime AD prevalence. RESULTS: The prevalence of AD accounted for 15.1% in 2002, and 16.1% in 2005. In the compared distinct 7- to 9-year-old populations the prevalence rates were 17.0% in 2002 and 17.1% in 2005. There were no statistically significant differences between the data of the two surveys. CONCLUSIONS: The results indicate the high prevalence rate of AD nearly approaching the markedly high values registered in the welfare countries, and could indicate that AD has reached a plateau in Hungary.     

Familiar and environmental factors influencing atopic dermatitis in the childhood

BACKGROUND: The increase in the incidence of atopic dermatitis (AD) in developed countries has been related to familiar and environmental factors. This survey was undertaken to investigate the family background, birthweight and the home environment of children suffering from AD in order to point out the possible factors that provoke the development of the disease. METHODS: The study uses data collected by means of self-administered questionnaires and discusses 461 cases of children (age 0-12) with active skin signs of AD. The control group comprised of 343 children (age 0-12) with no skin signs or positive lifetime history of AD. Associations between familiar and various home environmental factors and the risk of AD were calculated by means of odds ratios. RESULTS: There were statistically significant positive associations between atopic eczema symptoms and higher birthweight, small households, wall-to-wall carpets, as well as indoor-kept pets. Day-nursery attendance, heating system and indoor smoking, however, did not significantly alter the risk of the disease. CONCLUSIONS: Because of the limitations of a retrospective questionnaire study, further research is needed to confirm these associations and clarify whether they are causative.     

Prevalence of atopic dermatitis and serum IgE values in nursery school children in Ishigaki Island, Okinawa, Japan

There have been many studies of the prevalence of atopic dermatitis (AD), but few population-based epidemiologic studies measure the prevalence in Japan among children aged 5 years and younger. We examined the prevalence of AD, serum total IgE levels and specific IgE antibodies to 10 common allergens among children in Ishigaki Island, Okinawa, Japan in 2001. We also obtained information on the predictability of the U.K. Working Party diagnostic questionnaire criteria for AD in this population. Five hundred and sixty five children aged 5 years and younger were enrolled in this study with informed consent from their parents. The questionnaire of the U.K. Working Party diagnostic criteria for AD was translated into Japanese, and the parents completed the questionnaire sheet. Physical examination and blood sampling were done for all children. Thirty-nine out of the 565 (6.9%) children were diagnosed with AD by physical examination. The total and specific IgE levels were significantly higher in the children with AD than in those without AD. High levels of total IgE were found in 33.3% of the children with AD. A specific IgE to one or more allergens was detected in 64.1% of children with AD. However, a substantial population of children without AD also had high levels of total IgE (12.7%) and a specific IgE to one or more allergens (30.2%), and the increment of total and specific IgE levels was significantly associated with age. The percentage of positive answers to the questionnaire of the U.K. Working Party diagnostic criteria for AD was significantly higher in children with AD (59.0%) than in children without AD (5.3%) (P<0.0001). Its specificity was 94.7%. The false negative rate was 41%. In conclusion, the prevalence of AD was relatively low in children in Ishigaki Island. High levels of total IgE were found in only one third of children with AD under 5 years of age. The Japanese translated form of the questionnaire of the U.K. Working Party diagnostic criteria for AD should be refined to improve its sensitivity.     

Lifetime prevalence of self-reported atopic diseases in a population-based sample of elderly subjects: results of the ESTHER study

BACKGROUND: Prevalence studies of atopic diseases such as atopic dermatitis (AD), hay fever and allergic asthma have mostly been performed in children. Studies in the adult population are still rare. OBJECTIVES: We estimated the lifetime prevalence of different atopic diseases in an elderly population in Saarland, Germany. Additionally we investigated the association between atopic diseases and sociodemographic factors including age, gender, duration of school education (as a proxy measure of socioeconomic status), family history, and size of place of residence. METHODS: This study was conducted between June 2000 and December 2002 in the State of Saarland, Germany. Participants aged 50-75 years (n=9961) were recruited by their general practitioner in the context of a general health screening examination. All filled out a standardized questionnaire and reported whether a physician had ever diagnosed an atopic disease (hay fever, AD or asthma). RESULTS: Overall, 9949 subjects (mean age 62 years, 45% men) were included in this analysis. The lifetime prevalence of reported AD, hay fever and asthma was 4.3%, 8.3% and 5.5%, respectively. Lifetime prevalence of AD and asthma among women, and lifetime prevalence of hay fever among both genders, strongly decreased with age. Duration of school education ( 11 years) was strongly associated with AD (3.7%, 5.7%, 6.8%; P trend < 0.0001) and hay fever (7.2%, 11.2%, 12.8%; P trend < 0.0001), but only tentatively with asthma. CONCLUSIONS: The lifetime prevalence of AD is considerably lower in the elderly compared with the prevalence reported among younger adults in recent studies. Adults with a longer duration of school education appeared to have a higher risk for atopic diseases.     

Atopic dermatitis and melanocytic naevi

A study was performed to test the clinical impression that adults with severe atopic dermatitis (AD) have a low number of common naevi (CN). The number of CN > or = 2 mm was investigated in 51 Caucasian patients aged 20-63 years with severe AD since early childhood. The control group consisted of 379 randomly selected subjects, aged 30-50 years, investigated in an earlier study. Patients with AD had a significantly (P < 0.0001) lower total body count of CN (mean 9, median 5) compared with the control group (mean 67, median 53). It was also found that in the AD group there was a significant (P < 0.001) negative correlation between serum IgE and number of CN [r(s) = -0.50, 95% CI (-0.69; -0.24)]. The explanation for the low number of naevi that we have found in this highly selected subgroup of AD patients is not known. The atopic inflammation in the skin, genetics and treatment used for eczema are possible factors that may influence the formation of melanocytic naevi.     

Prevalence of atopic dermatitis in Japanese adults

BACKGROUND: Adult atopic dermatitis (AD) in Japan has become a significant social problem, with as many as one-third of adult patients with severe AD absenting themselves from work or classes due to aggravation of the disease. Reports of such patients have become increasingly common in recent years. Despite the pressing need for epidemiological studies to clarify the prevalence and distribution of AD and to determine its aetiology, no previous research has been carried out on the prevalence of AD within the adult population in Japan. OBJECTIVES: To clarify the prevalence of adult AD in Japan, using the U.K. Working Party's diagnostic criteria. METHODS: The subjects of this study were mostly government officials or their family members visiting the Medical Center of Health Science, Toranomon Hospital in Tokyo for annual health check-ups in the period from September 1997 to August 1998. Questionnaires completed by 10 762 persons (8076 men and 2686 women) aged 30 years or above were analysed. The questionnaire consisted of 14 questions on allergic disease. The U.K. Working Party's diagnostic criteria were used after translation into Japanese. Three types of prevalence were used as indicators of prevalence: point, 1-year and lifetime prevalence. RESULTS: The point prevalence, 1-year prevalence and lifetime prevalence of AD in Japanese adults were 2.9%, 3.0% and 3.3%, respectively. No significant statistical differences were observed between the sexes or among age groups within each sex. The survey indicated that 88.6% of those who had ever had AD were currently affected by active AD, while 93.4% of those who had had at least one episode of AD in the past had experienced an episode over the previous year. CONCLUSIONS: This study gives the first indication of the prevalence of adult AD among the Japanese, based on the U.K. criteria. Both the internal and external validity of this study are believed to be high; it would be safe to conclude that the 1-year prevalence of AD in Japanese adult populations living in urban areas is 3.0%.     

Prognosis and prognostic factors in adult patients with atopic dermatitis: a long-term follow-up questionnaire study

BACKGROUND: Atopic dermatitis (AD) is a chronic relapsing skin disease. Several investigations concerning the long-term prognosis of AD among children and teenagers have been performed but there are only few data among adults. OBJECTIVES: To investigate the prognosis and prognostic factors in adult patients with AD by a long-term follow-up (25-38 years). The prognostic factors were defined as those factors of importance for the persistence of AD. PATIENTS AND METHODS: A follow-up questionnaire was sent in November/December 1998 to 922 AD patients examined in our outpatient clinic between 1960 and 1973 among 1366 registered patients with AD. The patients were aged 20 years or older when they visited the clinic and 45 years or older when they answered the follow-up questionnaire. RESULTS: The response rate was 90.4%. The age range at the time of follow-up was 45-86 years (mean 55 years). Of the 833 patients who responded, 59% reported AD at some time during the last 12 months, which we defined as persistent AD. The mean value of clearance rate per person-years was 18%. One of the most important factors associated with persistence of AD was a head and neck dermatitis with or without other AD locations at the time of examination according to the old patient records. CONCLUSIONS: This study showed that the majority of adults with AD still had AD when they became older. This applies particularly if negative prognostic factors existed.