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Objective To examine asthma remission from childhood to middle age. Methods This was a population-based cohort study. In 1968 the Tasmanian Longitudinal Health Study enrolled 8583 7-year-old Tasmanian schoolchildren who were re-surveyed in 2004. Those reporting ever having asthma when last surveyed completed another questionnaire in 2007 ascertaining age at last asthma attack and asthma medication use. The main outcome measure was asthma remission, defined as no asthma attack for 2 years and no current asthma medication use, or no self-reported asthma in adult life but with parent-reported childhood asthma. Results Of 5729 respondents to the 2004 survey, 1238 self-reported asthma. A further 573 denied asthma, but had parent-reported childhood asthma, giving a study sample of 1811. Asthma had remitted in 1177 (65.0%) of whom 649 (55.1%) were male. Childhood (OR 0.38, 95% CI 0.25 to 0.58) and later-onset allergic rhinitis (0.42, 0.29 to 0.63), childhood (0.66, 0.47 to 0.94) and later-onset eczema (0.66, 0.47 to 0.92), maternal asthma (0.66, 0.47 to 0.92) and childhood chronic bronchitis (0.56, 0.41 to 0.76) were negatively associated with remission. There was weaker evidence for a negative association between passive smoking (0.75, 0.54 to 1.04) and lower socio-economic status (p-trend 0.09) and remission. Childhood-onset asthma (3.76, 2.58 to 5.49) was more likely to remit than adult-onset asthma. Adult smoking was positively associated with remission in childhood-onset asthma (1.49, 1.06 to 2.09). Sex did not influence remission. Conclusion While inherited factors cannot be changed, the effect of allergic rhinitis or eczema on asthma remission might be altered by early, aggressive treatment. Every effort should be made to lessen passive exposure to tobacco smoke. [ABSTRACT FROM AUTHOR]

Background: There is ongoing conjecture over whether childhood immunisation leads to an increased risk of developing atopic diseases. Objective: To examine associations between childhood immunisation and the risk of atopic disease. Method: Immunisation histories of 8443 Tasmanian children born in 1961 obtained from school medical records were linked to the Tasmanian Asthma Study. Associations between immunisation status and atopic diseases were examined while adjusting for possible confounders using multiple logistic regression. Results: Diphtheria immunisation was weakly associated with an increased risk of asthma by age 7 years (odds ratio (OR) 1 .3, 95% confidence interval (CI) 1 .1 to 1 .7), but there was no evidence of any association for four other vaccinations studied. An increased risk of eczema by age 7 years was associated with immunisation against diphtheria (OR 1 .5, 95% CI 1 .1 to 2.1), tetanus (OR 1 .5, 95% CI, 1 .1 to 2.0), pertussis (OR 1.5, 95% CI 1.1 to 1.9) and polio (OR 1.4, 95% CI 1.0 to 1.9) but not small pox. Similar but slightly weaker patterns of association were observed between the risk of food allergies and immunisation against diphtheria (OR 1 .5, 95% Cl 1 .0 to 2.1), pertussis (OR 1 .4, 95% CI 1 .1 to 1 .9), polio (OR 1 .4, 95% CI 1 .00 to 2.1) and tetanus (OR 1.30 95% Cl 0.99 to 1.70), but not with small pox. There was no evidence of associations between immunisation history and hay fever, or incidence of later-onset atopic outcomes. Conclusions: The few effects seen in this study are small and age-dependent, and nearly all our findings support numerous previous studies of no effect of vaccines on asthma. Based on these findings, the fear of their child developing atopic disease should not deter parents from immunising their children, especially when weighed against the benefits. [ABSTRACT FROM AUTHOR]

Purpose: To assess misclassification in adults reporting childhood asthma. Methods: The Tasmanian Asthma Survey commenced in 1968 when 8,583 7-year-old children attending school in Tasmania (participants) were studied. In 1991–1993, a stratified sample of 1,494 participants was studied. Their recall of childhood asthma was compared to their parents' prospectively gathered report. Results: Where participants had childhood asthma, those with current asthma, severe eczema, or hay fever were less likely to misclassify while females were more likely to misclassify. Where participants had no childhood asthma, misclassification was associated with current asthma, hay fever, or allergies. Conclusions: Retrospective self-assessment of childhood asthma is unreliable. [ABSTRACT FROM AUTHOR]

Background: The atopic march hypothesis proposes that eczema precedes the development of asthma and allergic rhinitis., Objective: We sought to assess the evidence for a causal effect of infantile eczema on childhood hay fever, asthma, or both., Methods: We used parental reports on infantile eczema and childhood asthma and hay fever for 3778 pairs of 7-year-olds matched to their sibling closest in age within 2 years from the Tasmanian Longitudinal Health Study. We analyzed paired sibling data using a logistic regression model that allowed inference about a causal effect of a familial predictor on a child's outcome by examining the change in association with their cosibling's predictor after adjusting for their own predictor status., Results: Siblings were concordant for infantile eczema (tetrachoric correlation, 0.40). For having both hay fever and asthma by age 7 years, the association with cosibling's eczema was an odds ratio (OR) of 1.98 (95% CI, 1.37-2.86), which reduced after adjusting for own eczema to an OR of 1.65 (95% CI, 1.17-2.34). For having hay fever only, the association with cosibling's eczema was an OR of 1.68 (95% CI, 1.22-2.31) before and an OR of 1.59 (95% CI, 1.19-2.14) after adjusting for own eczema. There was no association between having asthma only and cosibling's eczema (OR, 1.00; 95% CI, 0.77-1.30)., Conclusions: Eczema in infancy might have a causal effect on hay fever in children with and perhaps without asthma. The association of infantile eczema on asthma in children without hay fever, which might be early transient wheeze, is unlikely to be causal or familial. These findings have implications for hay fever prevention., (Copyright © 2012 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.)

The association between childhood immunizations and risk of atopic diseases is unclear. No study has examined possible associations between childhood immunizations and such diseases in middle age. The Tasmanian Longitudinal Health Study (TAHS) is a population based cohort study of respiratory disease. The TAHS participants were followed from 7 to 44 yrs of age. Immunizations during childhood were examined for any association with asthma and atopic disease at age 44 yrs. Multivariable regression models were used to estimate relative risks while adjusting for confounders. Cox regression was used to estimate the association between childhood immunizations and asthma developing after the age of 7 yrs. We found no association between any childhood immunization (Diphtheria, Tetanus, Pertussis, Polio, Smallpox) and asthma (ORs ranged from 0.87 to 1.17 p > 0.05), eczema (ORs ranged from 0.99 to 1.07 p > 0.05), food allergy (ORs ranged from 0.97 to 1.11 p > 0.05), or hay fever (ORs ranged from 1.02 to 1.05 p > 0.05) at age 44. Nor did we find any association between childhood immunizations and an increased risk of incident asthma after the age of 7 yrs (Diphtheria HR = 1.06, 95% CI 0.82, 1.36; Tetanus HR = 1.13, 95% CI 0.88, 1.44; Pertussis HR = 1.03, 95% CI 0.81, 1.30; Polio HR = 1.15, 95% CI 0.86, 1.54; Smallpox HR = 1.21, 95% CI 0.99, 1.48; DTP HR = 1.05, 95% CI 0.85, 1.30). Our analysis does not support any association between common childhood immunizations and risk of asthma and atopic disease in middle-age. Our findings should provide reassurance that in terms of life time risk of asthma and atopic disease, childhood immunization is safe.

Background: The literature regarding the association between breast-feeding and atopic diseases has been contradictory., Objective: We have assessed the relationship between breast-feeding and atopic disorders in a cohort followed into middle age., Methods: The Tasmanian Asthma Study is a population-based prospective cohort study that has followed participants from the age of 7 to 44 years. Exclusive breast-feeding in the first 3 months of life was examined as a risk factor for atopic diseases by using multiple logistic regression and generalized estimating equation analyses., Results: At age 7 years, exclusively breast-fed children with a maternal history of atopy had a marginally lesser risk of current asthma than those not exclusively breast-fed (odds ratio [OR], 0.8; 95% CI, 0.6-1.0). However, after age 7 years, the risk reversed, and exclusively breast-fed children had an increased risk of current asthma at 14 (OR, 1.46; 95% CI, 1.02-2.07), 32 (OR, 1.84; 95% CI, 1.06-3.3), and 44 (OR, 1.57; 95% CI, 1.15-2.14) years. Exclusively breast-fed children also had a reduced risk of food allergy at age 7 years but an increased risk of food allergy (OR, 1.26; 95% CI, 1.1-1.5) and allergic rhinitis (OR, 1.2; 95% CI, 1.0-1.3) at 44 years., Conclusion: Exclusively breast-fed babies with a maternal history of atopy were less likely to develop asthma before the age of 7 years, but more likely to develop asthma after the age of 7 years., Clinical Implications: The current recommendation to breast-feed high-risk infants for protection against early wheezing illness can be confirmed. However, the recommendation should be reconsidered for protection against allergic asthma and atopy in the longer term.

Objective: To trace all participants 36 years after the original Tasmanian Asthma Study (TAS)., Methods: In 1968, the TAS investigated asthma in 8,583 children who were born in 1961. We attempted to trace these participants in 2002-04 using names, dates of birth and gender. Current addresses were sought by computer linkage to the Commonwealth Electoral Roll, the Medicare database and the Tasmanian marriage records. Computer linkage was conducted with the National Death Index (NDI). Siblings of participants were also linked to the Commonwealth Electoral Roll and those identified were sent a letter requesting the participant's address. The Australian Twin Registry (ATR) and the 1991-93 TAS substudy were used to locate participant addresses., Results: After three rounds of electoral roll linkage, 56% of all cohort members were traced. Name changes were identified for 49% of the 3,477 females not initially matched to the electoral roll using linkage to marriage records. NDI linkage yielded a 0.7% match. Medicare linkage identified addresses for 27% of the 1,982 remaining participants. Writing to siblings located 60% of 1,661 participants. One hundred and eighty-three participants were matched to the 1991-93 TAS and 23 twins matched to the ATR. Overall, 81.5% of the cohort members were identified., Conclusions: With these methods, we have been able to trace a possible address for a large portion of the original participants, with the electoral roll linkage being the most useful., Implications: It is possible to trace Australians for follow-up studies using electronic linkage, although without unique identifiers it is labour and resource intensive and requires matching to several databases.