Aspergillus fumigatus is commonly found in cystic fibrosis (CF) airways. Our aim was to assess the relationship between A. fumigatus chronic colonization and lung function in CF patients. A case-control study of CF patients born from 1989 to 2002 was performed. Medical records were reviewed from the time of initial diagnosis until December 2013. Chronic colonization was defined as two or more positive sputum cultures in a given year. Each patient chronically colonized with A. fumigatus was matched with three control patients (never colonized by A. fumigatus) for age, sex, and year of birth (±3 years). A number of parameters were recorded and analyzed prospectively. The primary outcome measure was the difference in forced expiratory volume in 1 s (FEV1) in percent predicted between groups. Linear mixed models were used for longitudinal analyses to evaluate the relationship between A. fumigatus chronic colonization and lung function during a 7-year period and study the lung function 4 years before the time of enrollment (t0). Twenty patients had chronic colonization and were matched with 60 controls. A significant difference in lung function was detected throughout the 7-year period after adjustment for confounders (est = 8.66, p = 0.020). Four years before t0, FEV1 baseline was the only factor associated with the course of lung function (est = 0.64, p< 0.001) and was significantly different between groups (p = 0.001). In conclusion, a decreased FEV1 baseline appears to be a risk factor for chronic colonization by A. fumigatus, which, in turn, may cause a faster deterioration of lung function.
Respiratory muscle function in patients with cystic fibrosis (CF) can be assessed by measurement of maximal inspiratory pressure (Pimax ), maximal expiratory pressure (Pemax ), and pressure-time index of the respiratory muscles (PTImus ). We investigated the differences in maximal respiratory pressures and PTImus between CF patients with no gross hyperinflation and healthy controls and described the effects of pulmonary function and nutrition impairment on respiratory muscle function in this group of CF patients. Forced expiratory volume in 1 sec (FEV1 ), forced vital capacity (FVC) and maximal expiratory flow between 25% and 75% of VC (MEF25-75 ), body mass index (BMI), upper arm muscle area (UAMA), Pimax , Pemax , and PTImus were assessed in 140 CF patients and in a control group of 140 healthy subjects matched for age and gender. Median Pimax and Pemax were significantly lower in CF patients compared to the controls [Pimax = 74 (57-94) in CF vs. 84 (66-102) in controls, P = 0.009], [Pemax = 71 (50-95) in CF vs. 84 (66-102) in controls, P < 0.001]. Median PTImus in CF patients compared to controls was significantly increased [PTImus = 0.110 (0.076-0.160) in CF vs. 0.094 (0.070-0.137) in controls, P = 0.049] and it was significantly higher in CF patients with impaired pulmonary function. In CF patients, PTImus was significantly negatively related to upper arm muscle area (r = 0.184, P = 0.031). These findings suggest that CF patients with no severe lung disease compared to healthy subjects exhibit impaired respiratory muscle function, while CF patients with impaired pulmonary function and nutrition indices exhibit higher PTImus values.
BACKGROUND: Chronic infection with Pseudomonas aeruginosa in patients with cystic fibrosis (CF) is associated with increased morbidity. Chronic infection can cause limb and respiratory muscle compromise. Respiratory muscle function can be assessed via maximal inspiratory pressure (P Imax ), maximal expiratory pressure (P Emax ), and the pressure-time index of the respiratory muscles (PTI mus ). We studied the effect of chronic P. aeruginosa infection on respiratory muscle function in patients with CF. METHODS: This cross-sectional study assessed P Imax , P Emax , PTI mus , FEV 1 , FVC, maximum expiratory flow during the middle half of the FVC maneuver, body mass index, and upper arm muscle area in 122 subjects with CF, in 4 subgroups matched for age and sex at different stages of P. aeruginosa infection, according to the Leeds criteria. We compared respiratory muscle function in the subgroups according to P. aeruginosa infection state. RESULTS: Median P Imax was significantly lower in CF subjects with chronic P. aeruginosa infection (P Imax ؍ 62 cm H 2 O), compared to subjects who were never infected (P Imax ؍ 86 cm H 2 O, P ؍ .02), free of infection (P Imax ؍ 74 cm H 2 O, P ؍ .01), or intermittently infected (P Imax ؍ 72 cm H 2 O, P ؍ .02). Median PTI mus was significantly increased in CF subjects with chronic P. aeruginosa infection (PTI mus ؍ .142), compared to subjects who were free of infection (PTI mus ؍ .102, P ؍ .006). Median upper-arm muscle area was significantly lower in CF subjects with chronic P. aeruginosa infection (upper-arm muscle area ؍ 2,219 mm 2 ), compared to subjects who were never infected (2,754 mm 2 , P ؍ .03), free of infection (2,678 mm 2 , P ؍ .01), or intermittently infected (2,603 mm 2 , P ؍ .04). Multivariate logistic regression revealed P. aeruginosa state of infection as a significant determinant of PTI mus (P ؍ .03) independently of sex, upper-arm muscle area, and FEV 1 . CON-CLUSIONS: CF subjects with chronic P. aeruginosa infection exhibited impaired respiratory muscle function and decreased inspiratory muscle strength, and chronic P. aeruginosa infection independently impacts respiratory muscle function in subjects with CF.
These results suggest that CF patients that undertake regular aerobic exercise maintain higher indices of respiratory muscle strength and lower PTImus values, while increased UAMA values in exercising patients highlight the importance of muscular competence in respiratory muscle function in this population.
Aspergillus fumigatus isolation in cultures from respiratory specimens of patients with cystic fibrosis (CF) is quite common; however, the role of A. fumigatus as a pathogen and whether its presence is associated with progression of pulmonary disease remain unclear. We investigated the association between inhaled corticosteroids and the recovery of A. fumigatus by performing a retrospective cohort study of CF patients born between 1988 and 1996. The patients' medical records from their first visit to the CF Center until December 2010 were reviewed. Outcomes were the occurrence of A. fumigatus first isolation, chronic colonization, or the last visit at the CF Center. A number of possible confounders were included in the multivariate logistic regression analysis in order to identify an independent association between inhaled corticosteroids and colonization status. A total of 121 patients were included in the study. Thirty-nine patients (32.2%) had at least one positive culture and 14 (11.6%) developed chronic colonization. Multivariate logistic regression analysis was used to determine the independent effect of inhaled corticosteroids on the odds of first isolation (odds ratio [OR], 1.165; 95% confidence interval [CI], 1.015-1.337; P = 0.029) and chronic colonization (OR, 1.180; 95% CI, 1.029-1.353; P = 0.018). In conclusion, A. fumigatus first isolation and chronic colonization are associated with the duration of inhaled corticosteroid treatment.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.