Don B. Sanders

Pulmonary exacerbations are associated with subsequent FEV1 decline in both adults and children with cystic fibrosis

Patients with cystic fibrosis (CF) frequently experience pulmonary exacerbations that may lead to a faster subsequent decline in pulmonary function; however, this relationship has not been clearly established. The purpose of this study was to determine the association between the frequency of pulmonary exacerbations and subsequent forced expiratory volume in 1 sec (FEV1) decline in adults and children with CF.

Return of FEV1 after pulmonary exacerbation in children with cystic fibrosis.

Lung function (FEV1) generally improves during treatment of pulmonary exacerbations in patients with cystic fibrosis (CF). However, it is unclear how often return to previous baseline FEV1 is achieved.

Outcomes of Infants With Indeterminate Diagnosis Detected by Cystic Fibrosis Newborn Screening

BACKGROUND AND OBJECTIVES: Cystic fibrosis transmembrane conductance regulator–related metabolic syndrome (CRMS) describes asymptomatic infants with a positive cystic fibrosis (CF) newborn screen (NBS) but inconclusive diagnostic testing for CF. Little is known about the epidemiology and outcomes of CRMS. The goal of this study was to determine the prevalence, clinical features, and short-term outcomes of infants with CRMS. METHODS: We analyzed data from the US CF Foundation Patient Registry (CFFPR) from 2010 to 2012. We compared demographic, diagnostic, anthropometric, health care utilization, microbiology, and treatment characteristics between infants with CF and infants with CRMS. RESULTS: There were 1983 infants diagnosed via NBS between 2010 and 2012 reported to the CFFPR. By using the CF Foundation guideline definitions, 1540 and 309 infants met the criteria for CF and CRMS, respectively (CF:CRMS ratio = 5.0:1.0). Of note, 40.8% of infants with CRMS were entered into the registry with a clinical diagnosis of CF. Infants with CRMS tended to have normal nutritional indices. However, 11% of infants with CRMS had a positive Pseudomonas aeruginosa respiratory tract culture in the first year of life. CONCLUSIONS: CRMS is a common outcome of CF NBS, and some infants with CRMS may develop features concerning for CF disease. A substantial proportion of infants with CRMS were assigned a clinical diagnosis of CF, which may reflect misclassification or clinical features not collected in the CFFPR.

Chest Computed Tomography Scores of Severity Are Associated with Future Lung Disease Progression in Children with Cystic Fibrosis

RATIONALE Most children with cystic fibrosis (CF) experience a slow decline in spirometry, although some children continue to be at risk for more significant lung disease progression. Chest computed tomography (CT) scans have been shown to be more sensitive to changes in lung disease than spirometry and may provide a means for predicting future lung disease progression. OBJECTIVES We hypothesized that Brody chest CT scan scores obtained in 2000 in a prospectively monitored cohort of children with CF would be associated with the most recent measures of lung disease severity. METHODS Brody chest CT scan scores were calculated for 81 children enrolled in the Wisconsin CF Neonatal Screening Project. Multivariable linear regression was used to determine associations between Brody scores and the most recent (age 21 yr or June 30, 2010, whichever was later) measures of CF lung disease. MEASUREMENTS AND MAIN RESULTS The mean observation time after the chest CT scan was 7.5 years. Brody chest CT scan scores were significantly associated with the most recent measures of spirometry (P < 0.001) and Wisconsin and Brasfield chest radiograph scores (P < 0.001). The strength of this association was much stronger than spirometry obtained near the time of the chest CT scan (P < 0.01) but not chest radiograph scores. CONCLUSIONS Chest CT scan scores are associated with future lung disease severity, and quantitative chest imaging(chest CT scan and chest radiograph scores) is more strongly associated with future lung disease severity than measures of spirometry. These findings may help clinicians identify patients at risk of future lung disease progression.

Risk factors for lung function decline in a large cohort of young cystic fibrosis patients

To identify novel risk factors and corroborate previously identified risk factors for mean annual decline in FEV1% predicted in a large, contemporary, United States cohort of young cystic fibrosis (CF) patients.

Short-term and long-term response to pulmonary exacerbation treatment in cystic fibrosis

Background Treatment of pulmonary exacerbations (PEx) in cystic fibrosis (CF) varies widely with no consensus on management practices or best indicators of therapeutic success. To design trials evaluating PEx treatment factors, we characterise the heterogeneity of PEx care in adults and paediatrics, and correlate it with measures of clinical response including short-term and long-term lung function changes, change in symptom severity score and time to next intravenous antibiotic therapy. Methods Data were used from a prospective observational study of patients with CF ≥10 years of age enrolled at six sites between 2007 and 2010. All were started on intravenous antibiotics for a clinically diagnosed PEx. Analysis of variance, logistic and Cox regression were used to examine the association of treatment factors with short-term and long-term clinical response. Results Of 123 patients with CF (60% women, aged 23.1±10.2 years), 33% experienced <10% relative improvement in FEV1 during treatment, which was associated with failing to recover baseline lung function 3 months after treatment (OR=7.8, 95% CI 1.9 to 31.6, p=0.004) and a longer time to next intravenous antibiotic (HR=0.48, 95% CI 0.27 to 0.85, p=0.011). Symptom improvement was observed but was not associated with subsequent lung function or time to next antibiotic therapy, which had a median recurrence time of 143 days. Conclusions Immediate symptomatic or respiratory response to PEx treatment did not have a clear relationship with subsequent outcomes such as lung function or intravenous antibiotic-free interval. These results can inform future research of treatment regimens for PEx in terms of interventions and outcome measures. Trial registration NCT00788359 (www.clinicaltrials.gov).

Risk factors for the progression of cystic fibrosis lung disease throughout childhood.

RATIONALE Previous studies of risk factors for progression of lung disease in cystic fibrosis (CF) have suffered from limitations that preclude a comprehensive understanding of the determinants of CF lung disease throughout childhood. The epidemiologic component of the 27-year Wisconsin Randomized Clinical Trial of CF Neonatal Screening Project (WI RCT) afforded us a unique opportunity to evaluate the significance of potential intrinsic and extrinsic risk factors for lung disease in children with CF. OBJECTIVES Describe the most important intrinsic and extrinsic risk factors for progression of lung disease in children with CF. METHODS Variables hypothesized at the onset of the WI RCT study to be determinants of the progression of lung disease and potential risk factors previously identified in the WI RCT study were assessed with multivariable generalized estimating equation models for repeated measures of chest radiograph scores and pulmonary function tests in the WI RCT cohort. MEASUREMENTS AND MAIN RESULTS Combining all patients in the WI RCT, 132 subjects were observed for a mean of 16 years and contributed 1,579 chest radiographs, and 1,792 pulmonary function tests. The significant determinants of lung disease include genotype, poor growth, hospitalizations, meconium ileus, and infection with mucoid Pseudomonas aeruginosa. The previously described negative effect of female sex was not seen. CONCLUSIONS Modifiable extrinsic risk factors are the major determinants of progression of lung disease in children with CF. Better interventions to prevent or treat these risk factors may lead to improvements in lung health for children with CF.

The Sensitivity of Lung Disease Surrogates in Detecting Chest CT Abnormalities in Children With Cystic Fibrosis

Chest CT scans detect structural abnormalities in children with cystic fibrosis (CF), even when pulmonary function tests (PFTs) are normal. The use of chest CT is limited in clinical practice, because of concerns over expense, increased resource utilization, and radiation exposure. Quantitative chest radiography scores are useful in detecting mild lung disease, but whether they are sensitive to the presence of CT scan abnormalities has not been evaluated.

Standardized Treatment of Pulmonary exacerbations (STOP) study: Physician treatment practices and outcomes for individuals with cystic fibrosis with pulmonary exacerbations

BACKGROUND Pulmonary Exacerbations (PEx) are associated with increased morbidity and mortality in individuals with CF. PEx management practices vary widely, and optimization through interventional trials could potentially improve outcomes. The object of this analysis was to evaluate current physician treatment practices and patient outcomes for PEx. METHODS The Standardized Treatment of Pulmonary Exacerbations (STOP) observational study enrolled 220 participants ≥12years old admitted to the hospital for PEx at 11 U.S. CF centers. Spirometry and daily symptom scores were collected during the study. Physicians were surveyed on treatment goals and their management practices were observed. Treatment outcomes were compared to stated goals. RESULTS The mean (SD) duration of IV antibiotic treatment was 15.9 (6.0) days. Those individuals with more severe lung disease (<50% FEV1) were treated nearly two days longer than those with >50% FEV1. Physician-reported FEV1 improvement goals were 10% (95% CI: 5%, 14%) lower for patients with 6-month baseline FEV1 ≤50% predicted compared with those with 6-month baseline FEV1 >50% predicted. There were clinically and statistically significant improvements in symptoms from the start of IV antibiotic treatment to the end of IV antibiotic treatment and 28days after the start of treatment. The mean absolute increase in FEV1 from admission was 9% predicted at end of IV antibiotic treatment, and 7% predicted at day 28. Only 39% fully recovered lost lung function, and only 65% recovered at least 90% of lost lung function. Treatment was deemed successful by 84% of clinicians, although 6-month baseline FEV1 was only recovered in 39% of PEx. CONCLUSIONS In this prospective observational study of PEx, treatment regimens and durations showed substantial variation. A significant proportion of patients did not reach physicians treatment goals, yet treatment was deemed successful.

Early Life Growth Trajectories in Cystic Fibrosis are Associated with Pulmonary Function at Age 6 Years

OBJECTIVE To determine whether severity of lung disease at age 6 years is associated with changes in nutritional status before age 6 within individual children with cystic fibrosis (CF). STUDY DESIGN Children with CF born between 1994 and 2005 and followed in the CF Foundation Patient Registry from age ≤2 through 7 years were assessed according to changes in annualized weight-for-length (WFL) percentiles between ages 0 and 2 years and body mass index (BMI) percentiles between ages 2 and 6 years. The association between growth trajectories before age 6 and forced expiratory volume in 1 second (FEV1)% predicted at age 6-7 years was evaluated using multivariable linear regression. RESULTS A total of 6805 subjects met inclusion criteria. Children with annualized WFL-BMI always >50th percentile (N = 1323 [19%]) had the highest adjusted mean (95% CI) FEV1 at 6-7 years (101.8 [100.1, 103.5]). FEV1 at 6-7 years for children whose WFL-BMI increased >10 percentile points by age 6 years was 98.3 (96.6, 100.0). This was statistically significantly higher than FEV1 for children whose WFL-BMI was stable (94.4 [92.6, 96.2]) or decreased >10 percentile points (92.9 [91.1, 94.8]). Among children whose WFL-BMI increased >10 percentile points, achieving and maintaining WFL-BMI >50th percentile at younger ages was associated with significantly higher FEV1 at 6-7 years. CONCLUSIONS Within-patient changes in nutritional status in the first 6 years of life are significantly associated with FEV1 at age 6-7 years. The establishment of a clear relationship between early childhood growth measurements and later lung function suggests that early nutritional interventions may impact on eventual lung health.