Measures of body habitus are associated with lung function in adults with cystic fibrosis: a population-based study

What Do We Know about the Microbiome in Cystic Fibrosis? Is There a Role for Probiotics and Prebiotics?

Cystic fibrosis (CF) is a life-shortening genetic disorder that affects the cystic fibrosis transmembrane conductance regulator (CFTR) protein. In the gastrointestinal (GI) tract, CFTR dysfunction results in low intestinal pH, thick and inspissated mucus, a lack of endogenous pancreatic enzymes, and reduced motility. These mechanisms, combined with antibiotic therapies, drive GI inflammation and significant alteration of the GI microbiota (dysbiosis). Dysbiosis and inflammation are key factors in systemic inflammation and GI complications including malignancy. The following review examines the potential for probiotic and prebiotic therapies to provide clinical benefits through modulation of the microbiome. Evidence from randomised control trials suggest probiotics are likely to improve GI inflammation and reduce the incidence of CF pulmonary exacerbations. However, the highly variable, low-quality data is a barrier to the implementation of probiotics into routine CF care. Epidemiological studies and clinical trials support the potential of dietary fibre and prebiotic supplements to beneficially modulate the microbiome in gastrointestinal conditions. To date, limited evidence is available on their safety and efficacy in CF. Variable responses to probiotics and prebiotics highlight the need for personalised approaches that consider an individual’s underlying microbiota, diet, and existing medications against the backdrop of the complex nutritional needs in CF.

Pseudomonas aeruginosa, the type of mutation, lung function, and nutritional status in adults with cystic fibrosis

OBJECTIVE

The aim of this study was to describe the relationship between the prevalence of Pseudomonas aeruginosa (PA) and lung function, as well as the nutritional status and type of gene mutation in adult patients with cystic fibrosis (CF).

METHODS

This cross-sectional study evaluated 103 Polish adults with CF the following: • The occurrence of PA and the level of bacterial susceptibility to antibiotics; • Type of mutation in the CFTR gene; • Nutritional status assessed by body mass index (BMI), and • Lung function measured by forced expiratory volume in 1 s (FEV1%).

RESULTS

The absence or presence of PA and the level of bacterial resistance were significantly related to the type of gene mutation (P < 0.001). In patients with a severe mutation, PA more often was extensively drug resistant or pandrug resistant compared with Pseudomonas culture-negative patients or patients with mild or unclassified mutations on both alleles. Associations were found between the presence of PA and lower values of BMI (P < 0.001), and FEV1% (P < 0.001). The risk for PA occurrence and the development of bacterial resistance increased twice in the case of severe mutation (odds ratio [OR], 2.51; 95% confidence interval [CI], 1.62-3.89), four times when BMI decreased <18.5 (OR, 4.15; 95% CI, 1.43-10.08). and six times when FEV1% fell <40 (OR, 6.75; 95% CI, 3.11-14.64).

CONCLUSIONS

The presence of PA is associated with lower FEV1% and BMI values. Deterioration of lung function, undernutrition, and severe type of gene mutation are linked to a higher probability of PA acquisition and resistance to antibiotic treatment.

The prevalence, clinical status and genotype of cystic fibrosis patients living in Cuba using national registry data

BACKGROUND

We aimed to establish a national cystic fibrosis (CF) registry for Cuba, a developing country.

METHODS

Regional centres that deliver care for all CF patients provided information for a national database.

FINDINGS

The prevalence of CF in Cuba is 26.3 cases per 1,000,000 population. The median age at diagnosis is 2 years, and the median age of the total population was 15 years. Of those aged 16 years or older, the prevalence of Pseudomonas aeruginosa infection was 46%, the prevalence of Staphylococcus aureus infection was 36%, and 80% of individuals were receiving oral azithromycin. The commonest gene mutation was F508del which was observed in 50% of patients.

INTERPRETATION

These data demonstrate that it is possible to establish a national CF registry in a developing country such as Cuba. This provides baseline data to permit evaluation of health care delivery enable the spread of good clinical practice nationally.

Nutritional status and pulmonary outcome in children and young people with cystic fibrosis

BACKGROUND

Nutrition is closely related to mortality and pulmonary and respiratory muscle function in cystic fibrosis (CF) patients. We initially validated results from a bioelectrical impedance device against dual energy x-ray absorptiometry (DEXA). We then determined whether fat free mass assessed by a portable impedance device rather than body mass index (BMI) better correlated with pulmonary function, respiratory muscle strength and exercise capacity in CF patients.

METHODS

Eighteen young people and adults (median age 19, range 12-39 years) with CF had dual energy X-ray absorptiometry and direct segmental multi-frequency impedance analysis. Body composition, pulmonary function, respiratory muscle function and exercise tolerance using the impedance device were measured in 29 young people with CF with median age 15 (range 12-19) years.

MAIN FINDINGS

There was a significant correlation between impedance and absorptiometry results (r² = 0.947). Fat free mass correlated with the forced vital capacity z-score (r = 0.442, p = 0.016), maximal inspiratory pressure (r = 0.451, p = 0.014) and exercise tolerance (r = 0. 707, p < 0.001). BMI z-scores did not significantly correlate with pulmonary or respiratory muscle function. Subjects with a fat free mass z-score of ≤2 had a lower forced expiratory volume in 1 s z-score (p = 0.007), lower forced vital capacity z-score (p = 0.001), higher residual volume z-score (p = 0.042), lower maximal inspiratory pressure (p = 0.039), more days of intravenous antibiotics per year (p = 0.016) and a higher rate of chronic infections (p = 0.006).

PRINCIPAL CONCLUSIONS

Fat-free mass measured by impedance correlated better with pulmonary and respiratory muscle function and exercise capacity than BMI.

Weight gain during acute treatment of an initial pulmonary exacerbation is associated with a longer interval to the next exacerbation in adults with cystic fibrosis

Cystic fibrosis (CF) results in a variety of clinical phenotypes, including increased susceptibility to pulmonary infections [1] and malnutrition [2]. As a consequence, one of the priorities in the clinical care for individuals with a diagnosis of CF is to treat chest infections promptly [3], with the aim of minimising the decline in lung function that occurs in individuals who experience recurrent pulmonary exacerbations [4]. Optimising nutrition is another important consideration in the care of patients with CF [3]. It is well recognised that nutritional status and lung function are correlated [5] and that individuals with lower levels of nutrition have increased mortality [6] compared to those individuals with better nutrition.

Weight gain during treatment for a cystic fibrosis exacerbationhttp://ow.ly/f1zl30dU9AO

An overview of international literature from cystic fibrosis registries. Part 5: Update 2012-2015 on lung disease

Patient registry data is a tool for defining the clinical course and risk factors in patients with less common diseases like Cystic Fibrosis. Forty-one registry-based reports on lung disease in Cystic Fibrosis were published between 2011 and 2015. The aim of this review is to describe and discuss the results of these reports, focusing on the risk factors for lung disease progression, specific microbiologic pathogens (e.g., non-tuberculous mycobacteria), disease complications, comparisons between registries of different countries, the impact of socio-economic status, and evaluation of benefits and costs of therapies. Techniques for improved clinical trial design were also studied. Pediatr Pulmonol. 2016;51:1251-1263. © 2016 Wiley Periodicals, Inc.

Growth Deficiency in Cystic Fibrosis Is Observable at Birth and Predictive of Early Pulmonary Function

INTRODUCTION

Cystic fibrosis (CF) is a complex disease that includes both pulmonary and gastrointestinal challenges, resulting in decreased weight. Pulmonary symptoms of CF are extremely variable. Greater body mass at an early age is associated with improved pulmonary function, but it is unknown at what age weight becomes predictive of pulmonary disease severity. The purpose of this study was to investigate the relationship between birth weight and pulmonary function in CF.

METHODS

Birth weight and pulmonary data were obtained. Linear regressions were used to examine the relationship between these two variables. A one-tailed t-test was used to compare birth weights between CF patients and the national average.

RESULTS

Birth weight was significantly lower in babies with CF and correlated with pulmonary disease at ages 6 and 10 years but not with age at which Pseudomonas aeruginosa colonization was observed.

DISCUSSION

These data suggest that CF growth deficiency has prenatal origins. Early nutritional intervention for babies with CF and a low birth weight is warranted to maximize pulmonary potential.