Indoor pet allergen exposures modify the effects of chemical air pollutants on respiratory symptoms.

SETTING: Indoor volatile organic compound (VOC) levels, which are generally correlated with each other, may have an additive or synergistic effect on health. VOC synergy with allergens is a suspected mechanism affecting respiration.OBJECTIVE: To determine the effect of exposure to interactions between VOCs and allergens on respiratory symptoms in individuals aged ≥15 years.DESIGN: A national cross-sectional survey measured 20 VOCs and dog and cat aeroallergens in 490 main residential dwellings in France. A standardised questionnaire was used to elicit responses on respiratory conditions in 1012 inhabitants. Four VOC factor scores (linear combinations of VOCs) were generated using principal component analysis. In order to take into account the phenomenon of multi-pollution, marginal models were used to model the relationships between exposure to VOC mixture and respiratory conditions. Stratified models were used to examine the interaction between allergens and VOCs.RESULTS: The aromatic hydrocarbon score was associated with rhinitis and wheezing, the aliphatic hydrocarbon score with asthma and cough, the halogenated hydrocarbons with asthma, wheezing and rhinitis. Aldehydes and Can f1 had a significant synergistic effect on wheezing and rhinitis. Aliphatic hydrocarbons had an antagonist effect with Can f1 on wheezing.CONCLUSION: Our data support evidence of adverse effects of exposure to VOC mixture on respiratory conditions; this effect is aggravated in the presence of pet allergens.

Persistence of apremilast in moderate-to-severe psoriasis: a real-world analysis of 14 147 apremilast- and methotrexate-naive patients in the French National Health Insurance database.

BACKGROUND: Real-world data on the persistence of apremilast vs. methotrexate are inconclusive. OBJECTIVES: To assess and compare the long-term persistence of apremilast and methotrexate in a large cohort of patients with psoriasis. METHODS: All adult patients with psoriasis registered in the French national health insurance database ('Système National des Données de Santé') between 2009 and 2017 were eligible for inclusion. The study population comprised apremilast- and methotrexate-naive patients, defined as those with a first prescription of apremilast or methotrexate. Levels of persistence were compared using a Cox model with propensity-score matching that included potential confounders (notably age, sex, psoriatic arthritis, comorbidities and previous exposure to topical and systemic treatments). RESULTS: In this nationwide population-based cohort, 14 147 adult patients with psoriasis (mean age 52·3 years, 55·2% male) were found to be naive to both apremilast and methotrexate. After propensity-score matching, two subgroups of 4805 patients with similar baseline characteristics were included, of whom 3207 apremilast-treated patients and 2736 methotrexate-treated patients discontinued their treatment. Kaplan-Meier survival propensity-score analyses revealed a discontinuation rate of 69% for apremilast and 59% for methotrexate in the first year of treatment. Apremilast-treated patients had a higher risk of discontinuation than methotrexate-treated patients when considering the study population as a whole (hazard ratio 1·28, 95% confidence interval 1·23-1·34) or in a propensity-score-matched analysis (hazard ratio 1·34, 95% confidence interval 1·27-1·41; P < 0·001). CONCLUSIONS: Our real-world data suggest that in the first year of treatment, the discontinuation rate was significantly higher for apremilast-treated patients than for methotrexate-treated patients, regardless of the previous therapeutic lines received. What's already known about this topic? Psoriasis is a common chronic, relapse-remitting, inflammatory skin disease associated with severe psychosocial impact. Apremilast, a phosphodiesterase 4 inhibitor, is one of the most recently commercialized psoriasis drugs. Little is known about the long-term clinical effectiveness of apremilast. What does this study add? The discontinuation rate at 1 year for apremilast was 69%, compared with 58% for methotrexate, in a nationwide population-based cohort including 14 147 nonselected adult patients with psoriasis. Patients in the apremilast cohort had a higher risk of discontinuation than patients in the methotrexate cohort using propensity-score matching, including potentially relevant individual risk factors such as age, sex, comorbidities and psoriatic arthritis, and regardless of the previous therapeutic lines received. In daily practice, physicians should take these results into account when choosing between methotrexate and apremilast as a first-line systemic therapy.