Impact of childhood asthma on growth trajectories in early adolescence: Findings from the Childhood Asthma Prevention Study (CAPS).

BACKGROUND AND OBJECTIVE: Understanding the associations between childhood asthma and growth in early adolescence by accounting for the heterogeneity of growth during puberty has been largely unexplored. The objective was to identify sex-specific classes of growth trajectories during early adolescence, using a method which takes the heterogeneity of growth into account and to evaluate the association between childhood asthma and different classes of growth trajectories in adolescence. METHODS: Our longitudinal study included participants with a family history of asthma born during 1997-1999 in Sydney, Australia. Hence, all participants were at high risk for asthma. Asthma status was ascertained at 8 years of age using data from questionnaires and lung function tests. Growth trajectories between 11 and 14 years of age were classified using a latent basis growth mixture model. Multinomial regression analyses were used to evaluate the association between asthma and the categorized classes of growth trajectories. RESULTS: In total, 316 participants (51.6% boys), representing 51.3% of the entire cohort, were included. Sex-specific classes of growth trajectories were defined. Among boys, asthma was not associated with the classes of growth trajectories. Girls with asthma were more likely than girls without asthma to belong to a class with later growth (OR: 3.79, 95% CI: 1.33, 10.84). Excluding participants using inhaled corticosteroids or adjusting for confounders did not significantly change the results for either sex. CONCLUSION: We identified sex-specific heterogeneous classes of growth using growth mixture modelling. Associations between childhood asthma and different classes of growth trajectories were found for girls only.

IGFBP-1 predicts all-cause mortality in elderly women independently of IGF-I.

OBJECTIVE: Previous studies on the insulin-like growth factor (IGF) system and mortality have shown ambiguous results. We investigated the association between IGF-I and insulin- like growth factor binding protein-1 (IGFBP-1) with all-cause mortality in an elderly female Swedish population. DESIGN AND METHODS: A prospective cohort study of elderly women (n=338) aged between 68 and 79 years (mean age 72 years) with a mean follow-up time of 9.9 years. Baseline data in the PRIMOS (Primary Health Care and Osteoporosis) study were collected between 1999 and 2001. Data of risk factors for cardiovascular disease were collected. Death rates were registered from the Swedish Cause of Death register for the period 1999-2009. Cox regression models were used to calculate hazard ratios. IGF-I and IGFBP-1 levels were separately divided into 3 groups (high, medium and low), with cut offs at the 30th and the 70th percentiles. RESULTS: In a fully adjusted Cox proportional hazard model, increased risk of mortality was shown for women with high serum levels of IGFBP-1, HR 3.03 (95% CI 1.64-5.63) and also with low serum levels of IGFBP-1, HR 1.98 (95% CI 1.03-3.81), compared to women with moderate levels. No significant association between IGF-I and mortality was observed. CONCLUSIONS: High and low serum insulin-like IGFBP-1 levels were associated with an increased risk of all-cause mortality in elderly women, compared to moderate levels.