Patterns of Growth and Decline in Lung Function in Persistent Childhood Asthma.

BACKGROUND: Tracking longitudinal measurements of growth and decline in lung function in patients with persistent childhood asthma may reveal links between asthma and subsequent chronic airflow obstruction. METHODS: We classified children with asthma according to four characteristic patterns of lung-function growth and decline on the basis of graphs showing forced expiratory volume in 1 second (FEV1), representing spirometric measurements performed from childhood into adulthood. Risk factors associated with abnormal patterns were also examined. To define normal values, we used FEV1 values from participants in the National Health and Nutrition Examination Survey who did not have asthma. RESULTS: Of the 684 study participants, 170 (25%) had a normal pattern of lung-function growth without early decline, and 514 (75%) had abnormal patterns: 176 (26%) had reduced growth and an early decline, 160 (23%) had reduced growth only, and 178 (26%) had normal growth and an early decline. Lower baseline values for FEV1, smaller bronchodilator response, airway hyperresponsiveness at baseline, and male sex were associated with reduced growth (P<0.001 for all comparisons). At the last spirometric measurement (mean [±SD] age, 26.0±1.8 years), 73 participants (11%) met Global Initiative for Chronic Obstructive Lung Disease spirometric criteria for lung-function impairment that was consistent with chronic obstructive pulmonary disease (COPD); these participants were more likely to have a reduced pattern of growth than a normal pattern (18% vs. 3%, P<0.001). CONCLUSIONS: Childhood impairment of lung function and male sex were the most significant predictors of abnormal longitudinal patterns of lung-function growth and decline. Children with persistent asthma and reduced growth of lung function are at increased risk for fixed airflow obstruction and possibly COPD in early adulthood. (Funded by the Parker B. Francis Foundation and others; ClinicalTrials.gov number, NCT00000575.).

Replication of LIN28B SNP association with age of menarche in young Filipino women.

BACKGROUND: Age of menarche, or the timing of first menses in girls, is a physiological trait that shows substantial genetic heritability. Earlier age of menarche is associated with increased childhood adiposity and with adult risk of obesity and cardiovascular disease. OBJECTIVES: We sought to further characterize the single nucleotide polymorphism (SNP) rs7759938 from the menarche locus LIN28B in 827 young Filipino women from the Cebu Longitudinal Health and Nutrition Survey (CLHNS). METHODS: We tested rs7759938 for additive association with age of menarche and also tested whether childhood adiposity, as measured by body mass index (BMI) at age 8, mediated this relationship. RESULTS: We observed nominal association of rs7759938 with age of menarche (ß = -0.118 years, 95% confidence interval = (-0.216, -0.020), P = 0.019) with an effect direction consistent with the previous report. We also observed suggestive evidence that the effect of the SNP on age of menarche was independent of childhood BMI. CONCLUSIONS: These data confirm the strongest gene reported in Europeans (LIN28B) as a contributor to age of menarche in an Asian population.