Factors associated with self-assessed asthma severity.

BACKGROUND: Asthma severity can be estimated as the level of medication needed to achieve asthma control or by the patient's subjective assessment. Factors associated with self-assessed asthma severity are still incompletely explored. AIM: The aim was to study factors associated with self-assessed moderate or severe asthma. METHOD: In total, 1828 randomly selected asthma patients from primary (69%) and secondary (31%) care, completed a questionnaire including items about patient characteristics, comorbidity, the Asthma Control Test (ACT), emergency care visits and a scale for self-assessed asthma severity. Logistic regression was used to analyze associations with the dependent variable, self-assessed moderate or severe asthma in the entire study population and stratified by sex. RESULTS: Of the patients, 883 (45%) reported having moderate or severe asthma. Factors independently associated with self-assessed moderate or severe asthma were age >60 years (OR [95% CI] 1.98 [1.37-2.85]), allergic rhino-conjunctivitis (1.43 [1.05-1.95]), sinusitis (1.45 [1.09-1.93]), poor asthma control as measured by ACT <20 (5.64 [4.45-7.16]) and emergency care visits the previous year (2.52 [1.90-3.34]). Lower level of education was associated with self-assessed moderate/severe asthma in women (1.16 [1.05-2.43]) but not in men (0.90 [0.65-1.25]), p for interaction = .012. CONCLUSION: Poor asthma control, allergic rhino-conjunctivitis, recent sinusitis and older age were independently associated with self-assessed moderate or severe asthma. Important implications are that comorbid conditions of the upper airways should always be considered as part of asthma management, and that elderly patients may need extra attention.

Middle Ear Administration of a Particulate Chitosan Gel in an in vivo Model of Cisplatin Ototoxicity.

BACKGROUND: Middle ear (intratympanic, IT) administration is a promising therapeutic method as it offers the possibility of achieving high inner ear drug concentrations with low systemic levels, thus minimizing the risk of systemic side effects and drug-drug interactions. Premature elimination through the Eustachian tube may be reduced by stabilizing drug solutions with a hydrogel, but this raises the secondary issue of conductive hearing loss. AIM: This study aimed to investigate the properties of a chitosan-based particulate hydrogel formulation when used as a drug carrier for IT administration in an in vivo model of ototoxicity. MATERIALS AND METHODS: Two particulate chitosan-based IT delivery systems, Thio-25 and Thio-40, were investigated in albino guinea pigs (n = 94). Both contained the hearing protecting drug candidate sodium thiosulfate with different concentrations of chitosan gel particles (25% vs. 40%). The safety of the two systems was explored in vivo. The most promising system was then tested in guinea pigs subjected to a single intravenous injection with the anticancer drug cisplatin (8 mg/kg b.w.), which has ototoxic side effects. Hearing status was evaluated with acoustically evoked frequency-specific auditory brainstem response (ABR) and hair cell counting. Finally, in vivo magnetic resonance imaging was used to study the distribution and elimination of the chitosan-based system from the middle ear cavity in comparison to a hyaluronan-based system. RESULTS: Both chitosan-based IT delivery systems caused ABR threshold elevations (p < 0.05) that remained after 10 days (p < 0.05) without evidence of hair cell loss, although the elevation induced by Thio-25 was significantly lower than for Thio-40 (p < 0.05). Thio-25 significantly reduced cisplatin-induced ABR threshold elevations (p < 0.05) and outer hair cell loss (p < 0.05). IT injection of the chitosan- and hyaluronan-based systems filled up most of the middle ear space. There were no significant differences between the systems in terms of distribution and elimination. CONCLUSION: Particulate chitosan is a promising drug carrier for IT administration. Future studies should assess whether the physical properties of this technique allow for a smaller injection volume that would reduce conductive hearing loss.