Lung Function In Young Adults Research Articles

Blood multiple heavy metals exposure and lung function in young adults: A prospective Cohort study in China

The content of single heavy metal in blood is associated with lung function decline, but there is little evidence on the joint effect of multiple heavy metals on lung function. To explore whether heavy metal mixture exposure is associated with lung function reduction among young adults. The study based on a cohort of 518 students recruited from a college in Shandong, China. We measured their lung function and blood heavy metal concentrations. The BKMR model was used to analyse the association between blood heavy metals mixture levels and lung function, and to identify the critical single heavy metal which contributes most to joint effects. As the sensitivity analysis, we used quantile g-computation model and GLM to explore the joint effect and independent effects of heavy metals. Our findings revealed a significant reduction of FVC and FEV1 levels after exposure to heavy metals mixture. An IQR increase in Cu was associated with a 0.079 L and 0.083 L decrease in FEV1 and FVC, respectively. And an IQR increase in Fe was associated with 0.036 L higher FEV1 and 0.033 L higher FVC. For adults, reducing blood heavy metals concentration might be an effective intervention to protect lung function.

Association of Muscle Fat Content and Muscle Mass With Impaired Lung Function in Young Adults With Obesity: Evaluation With MRI

Although low muscle mass is associated with decreased lung function, studies exploring the relationship between muscle fat content and lung function impairment are scarce. This study aimed to evaluate the association of muscle mass and fatty infiltration with lung function in young adults with obesity. We performed a retrospective cross-sectional study of patients aged 18-45 years with obesity who had impaired pulmonary function (case group, n=66) and those with normal pulmonary function (control group, n=198) by matching age, sex, body mass index (BMI), and height to assess whether muscle characteristics differed. Muscle mass and muscle fat content were assessed by MRI using a chemical shift-encoded sequence (IDEAL-IQ). A total of 264 patients were enrolled (124 females; mean age 32.0 years). The case group had lower muscle mass than the control group (p=0.012), and there was an association between low muscle mass and lung function impairment (odds ratio (OR), 3.74; 95% confidence interval (CI), 1.57-8.93). Furthermore, muscle fat content was significantly higher in cases compared to controls (7.4 (2.7) % vs. 6.2 (2.5) %, p=0.001). Multiple logistic regression analysis showed that muscle fat content was associated with a higher risk of impaired lung function (OR, 2.10; 95% CI, 1.65-2.66), regardless of adiposity and muscle mass. Both muscle fat content and muscle mass are associated with impaired lung function in young adults with obesity.

Association between mercury exposure and lung function in young adults: A prospective cohort study in Shandong, China

BackgroundMercury has been associated with many adverse health outcomes. However, limited studies have explored the association between blood mercury concentrations and lung function. ObjectiveTo examine the association between blood mercury concentrations and lung function among young adults. MethodsWe conducted a prospective cohort study among 1800 college students based on the Chinese Undergraduates Cohort in Shandong, China during August 2019 and September 2020. Lung function indicators including forced vital capacity (FVC, ml), forced expiratory volume in 1 s (FEV1, ml) and peak expiratory flow (PEF, ml) were collected with a spirometers (Chestgraph Jr. HI-101, Chest M.I., Tokyo, Japan). The blood mercury concentration was measured using inductively coupled plasma mass spectrometry. We divided participants into low (≤25 percentiles), intermediate (25–75 percentiles), and high (≥75 percentile) subgroups according to blood mercury concentrations. The multiple linear regression model was used to examine the associations between blood mercury concentrations and lung function changes. Stratification analyses by sex and fish consumption frequency were also conducted. ResultsThe results showed that each 2-fold increase in blood mercury concentrations was significantly associated with −70.75 ml [95 % confidence interval (CI): −122.35, −19.15] change in FVC, −72.68 ml (95%CI: −120.36, −25.00) in FEV1, and −158.06 ml (95%CI: −283.77, −32.35) in PEF. The effect was more pronounced among participants with high blood mercury and male participants. Participants who consumed fish more than once a week more likely to be affected by mercury. ConclusionOur study indicated that blood mercury was significantly associated with decreased lung function in young adults. It is necessary to implement corresponding measures to reduce the effect of mercury on the respiratory system, especially for men and people who consumed fish more than once a week.

Are BMI and adipokines associated with asthma, atopy and lung function in young adults previously hospitalized for bronchiolitis?

BackgroundChildren hospitalized for bronchiolitis have increased risk of asthma and low lung function persisting into adulthood, but the underlying mechanisms are poorly understood. Body mass index (BMI) and adipokines are associated with respiratory morbidity. We aimed to investigate if associations between BMI and adipokines and the outcomes asthma, atopy, and lung function differed between young adults previously hospitalized for bronchiolitis and control subjects. MethodsThis sub study of a historical cohort enrolled 185 young adults previously hospitalized for bronchiolitis and 146 matched control subjects. Exposures (BMI and the adipokines: adiponectin, leptin, resistin, and ghrelin) and outcomes (asthma, atopy, and lung function) were measured cross-sectionally at 17–20 years of age. Associations were tested in regression models, and differences between the post-bronchiolitis- and control group were tested by including interaction terms. ResultsBMI was associated with asthma and lung function, but we did not find that the associations differed between the post-bronchiolitis- and control group. We also found some associations between adipokines and outcomes, but only associations between adiponectin and forced vital capacity (FVC) and between resistin and current asthma differed between the groups (p-value interaction term 0.027 and 0.040 respectively). Adiponectin tended to be positively associated with FVC in the post-bronchiolitis group, with an opposite tendency in the control group. Resistin was positively associated with current asthma only in the control group. ConclusionThe increased prevalence of asthma and impaired lung function observed in young adults previously hospitalized for bronchiolitis do not seem to be related to growth and fat metabolism.

Blood eosinophils during bronchiolitis: Associations with atopy, asthma and lung function in young adults.

To study if blood eosinophils during bronchiolitis were associated with atopy, asthma and lung function in young adults and if these associations differed between respiratory syncytial virus (RSV) bronchiolitis and non-RSV bronchiolitis. This historical cohort enrolled 225 subjects. Blood eosinophils were measured during bronchiolitis in infancy, and the subjects were invited to a follow-up at 17-20 years of age including questionnaires for asthma and examinations of lung function and atopy. The level of eosinophils was positively associated with subsequent atopy in the unadjusted analysis, but not in the adjusted analysis, and not with asthma. There was a negative association between the level of eosinophils and forced vital capacity (FVC) (-0.11; -0.19, -0.02) and forced expiratory volume in first second (FEV1 ) (-0.12; -0.21, -0.03) (regression coefficient; 95% confidence interval). The non-RSV group had higher levels of eosinophils during bronchiolitis, but there was no interaction between the level of eosinophils and RSV status for any outcome. The level of eosinophils during bronchiolitis was negatively associated with lung function in young adult age, but we found no associations with atopy or asthma. These associations were not different after RSV bronchiolitis compared to non-RSV bronchiolitis.

Lung function in young adults born small for gestational age at term.

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Association of Ambient and Household Air Pollution with Lung Function in Young Adults in an Peri-urban Area of South-India: a cross-sectional study

Association of Ambient and Household Air Pollution with Lung Function in Young Adults in an Peri-urban Area of South-India: a cross-sectional study

Association of ambient and household air pollution with lung function in young adults in an peri-urban area of South-India: A cross-sectional study.

Although there is evidence for the association between air pollution and decreased lung function in children, evidence for adolescents and young adults is scarce. For a peri-urban area in India, we evaluated the association of ambient PM2.5 and household air pollution with lung function for young adults who had recently attained their expected maximum lung function. We measured, using a standardized protocol, forced expiratory volume in the first second (FEV1) and forced vital capacity (FVC) in participants aged 20-26years from the third follow-up of the population-based APCAPCS cohort (2010-2012) in 28 Indian villages. We estimated annual average PM2.5outdoors at residence using land-use regression. Biomass cooking fuel (a proxy for levels of household air pollution) was self-reported. We fitted a within-between linear-mixed model with random intercepts by village, adjusting for potential confounders. We evaluated 1,044 participants with mean age of 22.8 (SD=1) years (range 20-26years); 327 participants (31%) were female. Only males reported use of tobacco smoking (9% of all participants, 13% of males). The mean ambient PM2.5 exposure was 32.9 (SD=2.8) µg/m3; 76% reported use of biomass as cooking fuel. The adjusted association between 1µg/m3 increase in PM2.5 was -27ml (95% CI, -89 to 34) for FEV1 and -5 ml (95% CI, -93 to 76) for FVC. The adjusted association between use of biomass was -112ml (95% CI, -211 to -13) for FEV1 and -142ml (95% CI, -285 to 0) for FVC. The adjusted association was of greater magnitude for those with unvented stove (-158ml, 95% CI, -279 to -36 for FEV1 and -211ml, 95% CI, -386 to -36 for FVC). We observed negative associations between ambient PM2.5 and household air pollution and lung function in young adults who had recently attained their maximum lung function.

Lung function before and after COVID-19 in young adults: Apopulation-based study.

BackgroundThere is limited evidence on the long-term impact of mild-to-moderate coronavirus disease 2019 (COVID-19) on lung function among young adults.ObjectivesWe aimed to assess whether COVID-19 has a negative impact on lung function in young adults and whether asthma, allergic sensitization, or use of inhaled corticosteroids (ICSs) modifies a potential association.MethodsParticipants from the population-based BAMSE (Barn, Allergi, Miljö, Stockholm, Epidemiologi) cohort with spirometry assessed before (2016-2019) and after onset of the COVID-19 pandemic (2020-2021) were included. Serum levels of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) receptor-binding domain-specific IgG, IgM, and/or IgA (determined with ELISA) defined seropositivity. Mean change in lung function (ie, change in FEV1, forced vital capacity [FVC], and FEV1/FVC ratio expressed as percent of predicted [pp]) from before to after onset of the pandemic were compared between the seronegative and seropositive participants. In seropositive participants, change in lung function was assessed in relation to allergic sensitization and self-reported ICS use.ResultsOf the 853 included participants, 29% (n = 243) were seropositive. There were no differences in change in lung function between the seronegative and seropositive participants (for mean change in FEV1 pp [SD], seropositivity = 0.87% [4.79%] and seronegativity = 1.03% (4.76%) [P = .66] for difference using a t test; FVC pp (SD), seropositivity = 1.34% (4.44%) and seronegativity = 1.29% (4.27%) [P = .87]; and for FEV1/FVC pp (SD), seropositivity = –0.25% (3.13%) and seronegativity = –0.13% (3.15%) [P = .61]). Similar results were observed among participants with asthma (n = 147 [17%]). Among seropositive participants, allergic sensitization or ICS use did not influence lung function.ConclusionWe found no evidence of mild-to-moderate COVID-19 affecting lung function long term in a population-based cohort of young adults. Moreover, neither asthma nor allergic sensitization nor ICS use affected the results.

Life-time summer heat exposure and lung function in young adults: A retrospective cohort study in Shandong China.

The health impact of short-term heat exposure is well documented. However, limited studies explored the association between life-time summer heat exposure and lung function. To examine the association between life-time summer heat exposure and lung function among young adults. We conducted a retrospective cohort study among 1928 college students in Shandong, China from September 4, 2020 to November 15, 2020. Life-time summer heat exposure for participants were estimated based on the nearest station meteorological data after the participant's birth date and divided by their learning phases. Lung function indicators included forced vital capacity (FVC) and forced expiratory volume in 1s (FEV1). A multiple linear regression model was conducted to examine the associations between summer heat exposure and lung function. Stratificationanalysis by cooling facilities and respiratory diseases history were also conducted. The study subjects had a slight majority of women (58.8%), age 19.2±0.6years. Each 1°C increase in life-time summer mean temperature was associated with 1.07% [95% confidence interval (CI): -1.95-0.18%] decrease in FVC and 0.88% (95%CI: -1.71, -0.05%) decrease in FEV1. Participants with respiratory diseases and non-cooling facility users were more susceptible to summer heat exposure. The usage of fan and air condition could effectively reduce the deleterious heat effects on lung function. Life-time summer heat exposure is significantly associated with the reduction of lung function in young adults. Cooling facilities are necessary for pre-school children to reduce heat effects. Fan and air-condition are effective cooling facilities, especially for people with respiratory diseases.

Asthma, atopy and lung function in young adults after hospitalisation for bronchiolitis in infancy: impact of virus and sex

BackgroundHospitalisation for bronchiolitis is a risk factor for asthma and impaired lung function during childhood, but outcomes in young adults are poorly described. Our primary aim was to study the...

Preserved Long-Term Lung Function in Young Adult Survivors of Common Childhood and Adolescence Malignancies.

Purpose: We aimed to evaluate long-term lung function and respiratory outcomes in young adults who survived common pediatric malignancies, treated in a single center. Methods: We enrolled young adults who had been treated during their childhood or adolescence for hematological or solid cancer at our Pediatric Oncology Unit, and performed pulmonary function tests (PFT) and clinical evaluation. PFT included spirometry and Diffusing Capacity of Lung for Carbon Monoxide (DLCO). Results: We included 121 survivors, mean age 23 years at follow-up, median 15 years from diagnosis. The most common diagnoses were hematological malignancies, mainly acute lymphoblastic leukemia, whereas 31% of the patients were treated for nonhematological cancer, mainly neuroblastoma. Treatments consisted of chemotherapy alone or in combination with radiotherapy and/or hematopoietic stem cell transplantation. Most of the patients denied respiratory symptoms throughout the years. In the whole group only eight patients (6%) had abnormal PFT, consisting mainly in a restrictive pattern and reduced DLCO. PFT abnormalities were of mild degree in most of the cases. Overall, the mean values of forced vital capacity, forced expiratory volume in 1 second, and DLCO were normal, but lower in females, in those who received radiotherapy and in those treated for lymphoma. Conclusion: In a group of young adults, surviving the most common childhood malignancies, we found a preserved lung function after a median follow-up of 15 years. The constantly increasing survival in childhood cancer is now associated with a trend toward an improvement in long-term respiratory outcomes.

Effect of muscle distribution on lung function in young adults

Background At present, available research on the relationship between muscle distribution and respiratory function in healthy people is limited. Objective To study the relationship between muscle distribution and lung function in healthy young adults. Methods A total of 612 male and 1561 Female Chinese college students were recruited. visceral fat tissue (VAT), subcutaneous fat tissue (SAT), total body muscle mass (TMM), trunk muscle mass (TKMM), upper limb muscle mass (ULMM) and lower limb muscle mass (LLMM) was measured by body composition. Vital capacity (VC) was measured by spirometry instrument. Obesity classification was defined by muscle mass ratio (MMR), body mass index (BMI), body fat percentage (BFP), waist-to-hip ratio (WHR). Results Among these positive correlation parameters, male VC had a high positive correlation with TMM and LLMM, while female VC had a high positive correlation with TMM and TKMM. After the population was divided into MMR, BMI, BFP, and WHR, further analysis showed that VC was positively correlated with TMM for males with MMR-low muscle (r = 0.483; p < 0.05), BMI-underweight (r = 0.265; p < 0.05), BMI-overweight + obesity (r = 0.272; p < 0.05), BFP-low fat (r = 0.306; p < 0.05), and WHR-normal subgroups (r = 0.316; p < 0.05), while LLMM was positively correlated with VC in the MMR-normal muscle (r = 0.285; p < 0.05), BMI-normal (r = 0.305; p < 0.05), BFP-normal fat (r = 0.304; p < 0.05), and WHR obesity subgroups (r = 0.266; p < 0.05). VC was positively correlated with TMM for females with MMR-low muscle (r = 0.169; p < 0.05), MMR-normal muscle (r = 0.241; p < 0.05), BMI-underweight (r = 0.241; p < 0.05), BMI-normal (r = 0.288; p < 0.05), WHR normal (r = 0.275; p < 0.05), and BFP-low fat subgroups (r = 0.255; p < 0.05), while TKMM was positively correlated with VC in the BMI-overweight + obesity (r = 0.342; p < 0.05), WHR-obesity (r = 0.227; p < 0.05), and BFP-normal subgroups (r = 0.256; p < 0.05). Conclusions Muscle distribution in young adults is highly correlated with VC, and this relationship is affected by gender and body types. In general, for thin, VC is more positively correlated with TMM, and for normal weight or obese, VC is more positively correlated with LLMM for males but with TKMM for females, respectively, in comparison with other tested indices. Further studies will be required to evaluate the relationship between muscle distribution and vital capacity in young adults.

Low-level exposure to polycyclic aromatic hydrocarbons is associated with reduced lung function among Swedish young adults

BackgroundExposure to polycyclic aromatic hydrocarbons (PAHs) has been linked to adverse pulmonary effects. However, the impact of low-level environmental PAH exposure on lung function in early adulthood remains uncertain. ObjectivesTo evaluate the associations between urinary PAH metabolites and lung function parameters in young adults. MethodsUrinary metabolites of pyrene, phenanthrene, and fluorene were analysed in 1000 young adults from Sweden (age 22–25 years) using LC-MS/MS. Lung function and eosinophilic airway inflammation were measured by spirometry and exhaled nitric oxide fraction (FeNO), respectively. Linear regression analysis was used to evaluate associations between PAH metabolites and the outcomes. ResultsMedian urinary concentrations of 1-OH-pyrene, ∑OH-phenanthrene, and ∑OH-fluorene were 0.066, 0.36, 0.22 μg/L, respectively. We found inverse associations of ∑OH-phenanthrene and ∑OH-fluorene with FEV1 and FVC, as well as between 1-OH-pyrene and FEV1/FVC ratio (adjusted P < 0.05; all participants). An increase of 1% in ∑OH-fluorene was associated with a decrease of 73 mL in FEV1 and 59 mL in FVC. In addition, ∑OH-phenanthrene concentrations were, in a dose-response manner, inversely associated with FEV1 (B from −109 to −48 compared with the lowest quartile of ∑OH-phenanthrene; p trend 0.004) and FVC (B from −159 to −102 compared with lowest quartile; p-trend <0.001). Similar dose-response associations were also observed between ∑OH-fluorene and FEV1 and FVC, as well as between 1-OH-pyrene and FEV1/FVC (p-trend <0.05). There was no association between PAH exposure and FeNO, nor was there an interaction with smoking, sex, or asthma. ConclusionLow-level PAH exposure was, in a dose-response manner, associated with reduced lung function in young adults. Our findings have public health implications due to i) the widespread occurrence of PAHs in the environment and ii) the clinical relevance of lung function in predicting all-cause and cardiovascular disease mortality.

Effects of smoking and physical exercise on respiratory function test results in students of university: A cross-sectional study.

We explored the effects of smoking and exercise on pulmonary function (PF) in young adults.This was a 2-year, prospective cross-sectional study on university students. We recorded age, gender, weight, height, pulmonary symptoms, smoking status, and sports habits. Spirometry was used to evaluate lung function; we recorded the forced expiratory volume in 1 second (FEV1), the forced vital capacity (FVC), and the FEV1/FVC ratio.A total of 1014 (552 female, 464 male) subjects were included. Smokers reported significantly more wheezing and sputum production than nonsmokers, but exhibited better FVC and FEV1 values. Those who smoked less than half a pack/d had significantly poorer FVC and FEV1 levels than nonsmokers. Smokers exhibited significantly lower FEV1/FVC ratios than nonsmokers. Overall, those who exercised exhibited better FEV1 and FVC levels, but this was attributable entirely to females.The spirometric percentile data were adjusted for gender, age, and height, and used as indicators of health status (good: >90: average: 25–90, poor <25). ln males, PF was associated with regular exercise (good: 7.8, average: 6.5, poor: 14.2, P = .02). The smoking rate was higher in the “good” group (males: good: 31.3, average: 30, poor: 17.9, P = .02/females: good: 22.4, average: 17.9, poor: 10.4, P = .02).On multivariate regression analysis, above-average PF test results were associated with age (1.32 [1.04–1.69]) and exercising at least once per week (4.06 [1.16–14.20]) in males. In females, above-average results were associated with irregular exercise (2.88 [1.36–6.09]), age (1.85 [1.44–2.37]), and exercising until palpitations developed (0.18 [0.04–0.88]).Smoking improves lung function in young adults; these are “healthy smokers.” Physical activity did not improve lung function, but the absence of physical activity significantly worsened lung function.

Effects of fat distribution on lung function in young adults

AimsTo study the associations between fat distribution and lung functions in healthy subjects of young adults and to explore potential gender difference in these correlations.MethodsA total of 2101 adult participants were recruited. Height, weight, and vital capacity index (VCI) were measured and recorded according to the national physical fitness test standard. Body compositions, including body mass index (BMI), body fat percentage (BFP), waist-to-hip ratio (WHR), fat-free mass (FFM), trunk muscle mass (TMM), fat mass (FM), visceral fat area (VFA), visceral adipose tissue (VAT), and subcutaneous adipose tissue (SAT), were conducted using body composition analyzer. Data were analyzed by SPSS 20.0 software.ResultsWe found that male participants showed significantly higher BMI, WHR, FFM, TMM, VFA, and VCI, but lower FM, BFP, and SAT in comparison with women. However, there was no significant difference in VAT between the male and female. Lung functions represented by VCI were negatively correlated with FM, VAT, SAT, and VFA for both men and women (r < 0; P < 0.05). Among these negative correlations, VCI was more inversely correlated with VFA for men but with SAT for women, respectively. After dividing the whole populations by BMI, BFP, and WHR, further correlation analysis showed VCI was still more negatively correlated with VFA for all male subgroups (r < 0; P < 0.05). On the contrary, VCI was more negatively correlated with SAT in BMI-underweight, BMI-normal, BFP-low fat, BFP-normal fat, WHR-normal, and WHR-obese subgroups (r < 0; P < 0.05), while VFA and VAT was more inversely correlated with VCI in BMI- and BFP-overweight+obese subgroups (r < 0; P < 0.05).ConclusionsFat accumulation is highly associated with the vital capacity index in young adults. In general, VCI was more negatively correlated with VFA for men but with SAT for women, respectively, in comparison with other tested indices.

Prediction of lung function using handgrip strength in healthy young adults.

Positive association between physical activity and spirometry has been reported to be possibly attributed to handgrip strength (HGS), particularly in the elderly. However, the nature of the association between HGS and lung function in young adults is still unclear. This study investigated the prediction of lung function using HGS in young adults. A cross‐sectional analytical study was carried out on four hundred (400) apparently healthy medical students who are aged 16–30 years. Handgrip strength (dominant and nondominant) and lung function (FEV 1, FVC and PEFR) of these students were assessed using Jamar dynamometer and a portable spirometer, respectively. Data were analyzed using inferential statistics. Independent t‐test showed that the mean values of HGS and lung function of the males were significantly higher than the females (P < 0.0005). The relationship between HGS and lung function indices was significant (P < 0.0005) in all the participants but strongest for FEV 1 (r = 0.64). The regression analysis showed that in addition to gender and height, HGS was a significant (P < 0.0005) predictor of lung function. Regression equations were also proposed for the prediction of these lung function indices using HGS, gender and height. This study is the first to report HGS as a significant predictor of pulmonary function in healthy young adults living in a low‐resource country. Hence, its use could enhance medical practice in being an indicator of lung function status in healthy young adults.

Lung Function in Young Adults and Risk of Cardiovascular Events Over 29 Years: The CARDIA Study.

BackgroundDiminished peak lung function in young adulthood is a risk factor for future chronic obstructive pulmonary disease. The association between lung disease and cardiovascular disease later in life is well documented. Whether peak lung function measured in young adulthood is associated with risk of future cardiovascular events is unknown.Methods and ResultsCARDIA (The Coronary Artery Risk Development in Young Adults) study is a prospective, multicenter, community‐based, longitudinal cohort study including 4761 participants aged 18 to 30 years with lung function testing we investigated the association between lung health in young adulthood and risk of subsequent cardiovascular events. We performed Cox proportional hazards regression to test the association between baseline and years 10 and 20 pulmonary function with incident cardiovascular events. Linear and logistic regression was performed to explore the associations of lung function with development of risk factors for cardiovascular disease as well as carotid intima‐media thickness and coronary artery calcified plaque. At baseline, mean age (±SD) was 24.9±3.6 years. Baseline forced expiratory volume in 1 second (hazard ratio) per −10‐unit decrement in percent predicted forced expiratory volume in 1 second (hazard ratio, 1.18; 95% CI, 1.06–1.31 [P=0.002]) and FVC per −10‐unit decrement in percent predicted FVC (hazard ratio, 1.19; 95% CI, 1.06–1.33 [P=0.003]) were associated with future cardiovascular events independent of traditional cardiovascular risk factors. Baseline lung function was associated with heart failure and cerebrovascular events but not coronary artery disease events.ConclusionsLung function in young adulthood is independently associated with cardiovascular events into middle age. This association appears to be driven by heart failure and cerebrovascular events rather than coronary heart disease.Clinical Trial Registration URL: https://www.clinicaltrials.gov. Unique identifier: NCT00005130.

Year in review 2017: Chronic obstructive pulmonary disease and asthma.

Year in review 2017: Chronic obstructive pulmonary disease and asthma.

Does distance to a cystic fibrosis center impact health outcomes?

This paper considers the impact of geographic distance from cystic fibrosis centers on lung function in children, young adults, and adults with cystic fibrosis. Clinical patient-level data on 20 351 patients from 1986 to 2011 were evaluated from the Cystic Fibrosis Foundation National Patient Registry. We measure distance using a patient's zip code centroid to the center where they received care. A heteroscedastic mixed effects model was used to capture the association of distance with longitudinal variation in patients' lung function. Children, young adults, and adults in lower socioeconomic categories had a %FEV1 between 3 and 10 percentage-points lower than those living in higher income areas and those privately insured. For patients who changed distance categories, high distance was associated with lower lung function in young adults (P-value <0.001). For older patients we observed the reverse, suggesting that the choice to move farther away is associated with better health (P-value <0.001). For patients who did not change distance categories, only medium distance in children was significant (P-value = 0.01). Known confounding factors including age and CFTR mutation class were statistically significantly associated to health outcomes (P-value <0.001). This study shows distance is not found to be associated with health lung function among patients whose distance category remained unchanged during the analysis. For patients who move, the association of health with distance depends on the age of the patient; adult patients further from their care center are healthier. Overall, we find that socioeconomic and genetic factors appear to impact health outcomes to a greater extent.