Mucociliary clearance in patients with chronic asthma: Effects of beta(2) agonists

Chronic asthma is characterized by airway inflammation, mucus hypersecretion and impaired mucociliary clearance (MCC). We investigated baseline MCC and the acute effect of terbutaline in chronic asthmatics with sputum production while on long-term treatment with salmeterol in combination with inhaled corticosteroids (ICS). MCC was measured at baseline and in response to 1 mg terbutaline (or placebo) on three visits over 80 min in 16 asthmatics (52 +/- 13 years of age). Subjects who had greater than 10% absolute increase in MCC above baseline and placebo, after terbutaline, were categorized in group A and subjects who had less than 10% in group B. In group A subjects (n = 6), MCC increased from 23.7 +/- 4.0% at baseline to 43.7 +/- 4.9% with terbutaline (P < 0.0001) and to 34.4 +/- 5.7% with placebo (P < 0.01). In group B subjects (n = 10), MCC remained similar: 11.3 +/- 3.2% at initial baseline, 12.0 +/- 3.2% with terbutaline and 7.3 +/- 3.0% with placebo (P > 0.05). Group B subjects withdrew from all beta(2) agonists for a week and MCC was remeasured. After withdrawal, baseline MCC (7.0 +/- 1.8%) was similar to the initial baseline value (P > 0.1) and MCC with terbutaline (15.8 +/- 4.9%) was greater than baseline (P < 0.005) but remained abnormal in most subjects. Baseline percentage predicted FEV1 and FEF25-75% were 77.3 +/- 7.2 and 41.7 +/- 5.6 in group A and 59.9 +/- 8.1 and 29.5 +/- 8.4 in group B subjects, respectively. MCC was impaired in most of these asthmatics with persistent airway obstruction and sputum production, despite regular treatment with ICS and salmeterol. In addition, there was little or no stimulation of MCC acutely after terbutaline in most of these asthmatics.

Empirically validated treatments and child clinical interventions - Comment

This commentary argues that empirically validated treatments for child and youth behaviour and emotional difficulties are available, but they are relatively inaccessible to the vast majority of Australian children and their families. Although effective interventions have been developed, few children receive these services. There are many children who have identifiable problems or who are at increased risk for psychosocial problems whose needs have not been adequately addressed by either the research or the professional community. These include children in rural and remote areas, Aboriginal and Tones Strait Islander children, children of migrants, and children with chronic physical illnesses. A comprehensive, preventively focused clinical science of prevention is needed to improve the reach and impact of psychological services for children.

Asthma mortality in Australia 1920-94: Age, period, and cohort effects

Study objective-To investigate asthma mortality during 1920-94 in Australia in order to assess the relative role of period and birth cohort effects. Design-Asthma mortality (both sexes) was age standardised and examined for changes over time. The data were also examined for age, period, and cohort (APC) effects using Poisson regression modelling. Setting-National Australian mortality data. Participants-Population (both sexes) aged 15-34 years, 1920-94. Main results-Age adjusted period rates indicate an increase in asthma mortality during the 1950s, and increases and subsequent falls (epidemics) during the mid 1960s and late 1980s. APC modelling suggested an increasing cohort effect (adjusted for both age and period) from the birth cohort 1950-54 onwards. Period effects (adjusted for age and cohort) are characterised by an increase in the 1950s (possibly due to changes in diagnostic labelling), minimal or no increases in the mid 1960s and late 1980s (where period peaks had been noted when data were adjusted for age only), and declines in mortality risk subsequent to the periods where age-period analysis had noted increases. Thus, in Australia, some of the mid 1960s epidemic in asthma deaths, and all of the late 1980s mortality increase, seem to be attributable to cohort effects. Conclusions-The increase in asthma mortality cohort effect is consistent with empirical evidence of recent increases in prevalence (and presumably incidence) of asthma in Australia, and suggests the need for more research into the underlying environmental aetiology of this condition.