Socioeconomic Characteristics Are Major Contributors to Ethnic Differences in Health Status in Obstructive Lung Disease: An Analysis of the National Health and Nutrition Examination Survey 2007-2010

Asthma and Chronic Obstructive Pulmonary Disease

In the United States, asthma and chronic obstructive pulmonary disease (COPD) disproportionately affect African Americans, Puerto Ricans, and other minority groups. Compared with non-Hispanic whites, minorities have been marginalized and more frequently exposed to environmental risk factors such as tobacco smoke and outdoor and indoor pollutants. Such divergent environmental exposures, alone or interacting with heredity, lead to disparities in the prevalence, morbidity, and mortality of asthma and COPD, which are worsened by lack of access to health care. In this article, we review the burden and risk factors for racial or ethnic disparities in asthma and COPD and discuss future directions in this field.

Association between circadian syndrome and the prevalence of kidney stones in overweight adults: a cross-sectional analysis of NHANES 2007-2018

OBJECTIVE

To explore the association between circadian syndrome (CircS) and the prevalence of kidney stones in overweight people.

MATERIALS AND METHODS

A cross-sectional analysis was conducted based on the NHANES 2007-2018. Overweight people aged ≥ 20 years were the target population. Three multivariable logistic regression models were built to examine the association between CircS and kidney stones. Subgroup analysis based on age, gender, and race were also employed. Interaction and stratification analysis was also conducted to identify whether some factors modify the association.

RESULT

A total of 4,603 overweight participants were included in the study. The multivariable logistic regression suggested that CircS was positively associated with the prevalence of kidney stones (OR = 1.422, 95% CI 1.057 to 1.912). The subgroup analysis showed that the association was more obvious in females (OR = 1.604, 95% CI 1.023 to 2.516) or in the population aged 35 to 49 years old (OR = 2.739, 95% CI 1.428 to 5.254). Additionally, the same trend was present when people were Mexican American (OR = 3.834, 95% CI 1.790 to 8.215) or other races (OR = 4.925, 95% CI 1.776 to 13.656). The interaction and stratification analysis showed that the results above were robust.

CONCLUSION

CircS was positively associated with the prevalence of kidney stones in overweight people, especially people as females, aged 35 to 49, and Mexican Americans.

Multi-omic association study identifies DNA methylation-mediated genotype and smoking exposure effects on lung function in children living in urban settings

Impaired lung function in early life is associated with the subsequent development of chronic respiratory disease. Most genetic associations with lung function have been identified in adults of European descent and therefore may not represent those most relevant to pediatric populations and populations of different ancestries. In this study, we performed genome-wide association analyses of lung function in a multiethnic cohort of children (n = 1,035) living in low-income urban neighborhoods. We identified one novel locus at the TDRD9 gene in chromosome 14q32.33 associated with percent predicted forced expiratory volume in one second (FEV1) (p = 2.4x10-9; βz = -0.31, 95% CI = -0.41- -0.21). Mendelian randomization and mediation analyses revealed that this genetic effect on FEV1 was partially mediated by DNA methylation levels at this locus in airway epithelial cells, which were also associated with environmental tobacco smoke exposure (p = 0.015). Promoter-enhancer interactions in airway epithelial cells revealed chromatin interaction loops between FEV1-associated variants in TDRD9 and the promoter region of the PPP1R13B gene, a stimulator of p53-mediated apoptosis. Expression of PPP1R13B in airway epithelial cells was significantly associated the FEV1 risk alleles (p = 1.3x10-5; β = 0.12, 95% CI = 0.06-0.17). These combined results highlight a potential novel mechanism for reduced lung function in urban youth resulting from both genetics and smoking exposure.

Evaluation of Access to Care Barriers and Their Effect on General Health Status Among Native Hawaiian and Pacific Islander Adults

There is a paucity of information on access to care barriers faced by Native Hawaiian and Pacific Islander (NHPI) community. This study utilized the 2014 Native Hawaiian and Pacific Islander National Health Interview Survey (NHPI NHIS) data to evaluate access to care barriers among NHPI population and their effect on general health status. Access to care barriers were categorized as financial barrier (affordability) and non-financial barriers (availability, accommodation, acceptability, and accessibility). Overall, 13.7% reported of the fair/poor general health and over 30% reported at least one access to care barrier. Logistic regression model was used to evaluate how financial and non-financial barriers affect general health status, adjusting for socio-demographic variables such as age, poverty threshold, and marital status and health-related variables such as smoking status and chronic health conditions. Those who reported financial barrier (21.2%) were more likely to be in fair/poor general health (odds ratio 2.25, 95% confidence interval 1.43-3.56). Non-financial barrier, reported by 20.0% of the study population, was found to be not associated with general health status after adjusting for socio-demographic and health-related variables. Improving access to care among NHPI community could be achieved by identifying and addressing the barriers, which in turn could lead to improvement in the general health status among NHPI community.

Prevalence and burden of obstructive lung disease in the urban poor population of Ottawa, Canada: a community-based mixed-method, observational study

BACKGROUND

Globally the burden of Obstructive Lung Diseases (OLD) is growing, however its effect on urban poor populations with the high prevalence of tobacco dependence is virtually unknown. The purpose of this project is to estimate the prevalence and burden of OLD in the urban, low-income populations of Ottawa, Canada.

METHODS

The study presented in this paper was part of the PROMPT (Management and Point-of-Care for Tobacco Dependence) project; a prospective cohort study in a community-based setting (n = 80) with meaningful Patient Engagement from design to dissemination. Spirometry data, standardized questionnaires and semi-structured interviews from PROMPT were interpreted to understand the lung function, disease burden and social determinants (respectively) in this population.

RESULTS

The prevalence of OLD among those who completed spirometry (N = 64) was 45-59%. Generic and disease-specific quality of life was generally poor in all PROMPT participants, even those without OLD, highlighting the higher disease burden this vulnerable population faces. Quality of life was impacted by two major themes, including i) socioeconomic status and stress and ii) social networks and related experiences of trauma.

CONCLUSION

The prevalence and disease burden of OLD is significantly higher in Ottawa's urban poor population than what is observed in the general Canadian population who smoke, suggesting an etiological role of the social determinants of health. This urges the need for comprehensive care programs addressing up-stream factors leading to OLDs, including poor access and utilization of preventive healthcare addressing the social determinants of health.

TRIAL REGISTRATION

ClinicalTrails.gov - NCT03626064 , Retrospective registered: August 2018.

Low lung function in the developing world is analogous to stunting: a review of the evidence

Background: Low vital capacity, one of the consequences of restricted lung growth, is a strong predictor of cardiovascular mortality. Vital capacity is lower in the developing world than the developed world, even after adjusting for height, weight and gender. This difference is typically dismissed as ethnic variation, adjusted for by redefining normal. Whether this is a consequence of stunted lung growth, rather than just genetically smaller lungs, has not been investigated in detail. Therefore, we sought to compare factors implicated in both stunting and lung development, particularly in the developing world.

Methods: We conducted a manual screen of articles identified through Google Scholar and assessed risk of bias. No language restrictions were applied, so long as there was an associated English abstract. We queried VizHub (Global Burden of Disease Visualization Tool) and Google Dataset search engines for disease burden and genome wide association studies.  The scope of the article and the heterogeneity of the outcome measures reported required a narrative review of available evidence. To the extent possible, the review follows PRISMA reporting guidelines.

Results: Early life influences operate in synergism with genetic, environmental and nutritional factors to influence lung growth and development in children.  Low lung function and stunting have common anthropometric, environmental and nutritional correlates originating during early development. Similar anthropometric correlates shared chronic inflammatory pathways, indicated that the two conditions were analogous.

Conclusion: The analogy between poor lung function and stunting is conspicuous in the developing world, with malnutrition at the center of non -achievement of growth potential, susceptibility to infectious diseases and intrauterine programming for metabolic syndrome. This counter the idea of redefining the normal for lung function measurements, since observed inter-ethnic variations are likely a mix of natural genetic differences as well as differences in nurture such that reduced lung function reflects early life adversities.

Low lung function in the developing world is analogous to stunting: a review of the evidence

Background: Low vital capacity, one of the consequences of restricted lung growth, is a strong predictor of cardiovascular mortality. Vital capacity is lower in the developing world than the developed world, even after adjusting for height, weight and gender. This difference is typically dismissed as ethnic variation, adjusted for by redefining normal. Whether this is a consequence of stunted lung growth, rather than genetically smaller lungs, has not been investigated in detail. Therefore, we sought to compare factors implicated in both stunting and lung development, particularly in the developing world. Methods: We conducted a manual screen of articles identified through Google Scholar and assessed risk of bias. No language restrictions were applied, so long as there was an associated English abstract. We queried VizHub (Global Burden of Disease Visualization Tool) and Google Dataset search engines for disease burden and genome wide association studies.  The scope of the article and the heterogeneity of the outcome measures reported required a narrative review of available evidence. To the extent possible, the review follows PRISMA reporting guidelines. Results: Early life influences operate in synergism with environmental and nutritional factors to influence lung growth and development in children.  Low lung function and stunting have common anthropometric, environmental and nutritional correlates originating during early development. Similar anthropometric correlates and shared chronic inflammatory pathways indicated that the two conditions were analogous. Conclusion: The analogy between poor lung function and stunting is conspicuous in the developing world, where malnutrition lies at the center of non -achievement of growth potential, susceptibility to infectious diseases and intrauterine programming for metabolic syndrome. The common pathological mechanisms governing stunting and lung function deficits counter the idea of redefining the normal for lung function measurements.

Racial-ethnic disparities in self-reported health status among US adults adjusted for sociodemographics and multimorbidities, National Health and Nutrition Examination Survey 2011-2014

Objective: To investigate racial-ethnic disparities in self-reported health status adjusting for sociodemographic factors and multimorbidities.Design: A total of 9499 adult participants aged 20 years and older from the United States (US); reported by the National Health and Nutrition Examination Survey (NHANES), a cross-sectional survey - for years 2011-2014. The main outcome measure was self-reported health status categorized as excellent/very good, good (moderate), and fair/poor.Results: Of the NHANES participants, 40.7% reported excellent/very good health, 37.2% moderate health and 22.1% fair/poor health. There were 42.8% who were non-Hispanic whites, 20.2% were Hispanic, 23.8% were non-Hispanic blacks, and 13.2% were non-Hispanic Asians. Compared to non-Hispanic whites, Hispanics [Odds Ratio (OR) = 2.91, 95% Confidence Interval (CI) = 2.28-3.71] and non-Hispanic blacks [OR = 1.51, 95% CI = 1.26-1.83] were more likely to report fair/poor health, whereas, non-Hispanic Asians [OR = 1.42, 95% CI = 1.14-1.76] were more likely to report moderate health than excellent/very good health. Compared to those with no chronic conditions, participants with two or three chronic conditions [OR = 9.35, 95% CI = 7.26-12.00] and with four or more chronic conditions [OR = 38.10, 95% CI = 26.50-54.90] were more likely to report fair/poor health than excellent/very good health status.Conclusion: The racial-ethnic differences in self-reported health persisted even after adjusting for sociodemographics and number of multimorbidities. The findings highlight the potential importance of self-reported health status and the need to increase health awareness through health assessment and health-promotional programs among the vulnerable minority US adults.

Comorbidities and length of stay in chronic obstructive pulmonary disease patients

Chronic Obstructive Pulmonary Disease (COPD) has a significant burden on patients and the healthcare system. There is a link between COPD and comorbidities such as congestive heart failure (CHF), fluid and electrolyte disorders, and renal failure. This adds to the complexity of healthcare in these patients. The objective of this study is to determine if certain comorbidities affect length of stay. A sample of 3,399 patients with COPD were assessed from the Premier^© healthcare database. The cohort had a mean (standard deviation (SD)) age of 68.41 (10.85) years. The average number of comorbidities was 24.83 (10.46) with a mean length of stay (SD) of 11.64 (9.40) days. A negative binomial regression model was used to evaluate the impact that comorbidities have on the length of hospital stay. The authors found that the number of comorbidities was associated with an increased length of stay (r = .4596, p < .0001). Having at least one comorbidity was associated with a 13% greater length of stay (IRR = 1.13, 95% CI 1.11-1.15, p < 0.0001). CHF was associated with a 28% greater length of stay (IRR = 1.28, 95% CI 1.24-1.31, p < 0.0001). Fluid and electrolyte disorders were associated with a 2-fold greater length of stay (IRR = 2.57, 95% CI 2.52-2.62, p < 0.0001). Renal failure was associated with a 50% greater length of stay (IRR = 1.50, 95% CI 1.45-1.55, p < 0.0001). However, uncomplicated diabetes was associated with 13% shorter length of stay than not having uncomplicated diabetes (IRR = .87, 95% CI .82-.91, p < .0001). This study demonstrated that specific comorbidities have an impact on length of stay.

Explaining ethnic disparities in lung function among young adults: A pilot investigation

Background

Ethnic disparities in lung function have been linked mainly to anthropometric factors but have not been fully explained. We conducted a cross-sectional pilot study to investigate how best to study ethnic differences in lung function in young adults and evaluate whether these could be explained by birth weight and socio-economic factors.

Methods

We recruited 112 university students of White and South Asian British ethnicity, measured post-bronchodilator lung function, obtained information on respiratory symptoms and socio-economic factors through questionnaires, and acquired birth weight through data linkage. We regressed lung function against ethnicity and candidate predictors defined a priori using linear regression, and used penalised regression to examine a wider range of factors. We reviewed the implications of our findings for the feasibility of a larger study.

Results

There was a similar parental socio-economic environment and no difference in birth weight between the two ethnic groups, but the ethnic difference in FVC adjusted for sex, age, height, demi-span, father’s occupation, birth weight, maternal educational attainment and maternal upbringing was 0.81L (95%CI: -1.01 to -0.54L). Difference in body proportions did not explain the ethnic differences although parental immigration was an important predictor of FVC independent of ethnic group. Participants were comfortable with study procedures and we were able to link birth weight data to clinical measurements.

Conclusion

Studies of ethnic disparities in lung function among young adults are feasible. Future studies should recruit a socially more diverse sample and investigate the role of markers of acculturation in explaining such differences.

Undiagnosed Obstructive Lung Disease in the United States. Associated Factors and Long-term Mortality

RATIONALE

Understanding factors associated with undiagnosed obstructive lung disease and its impact on mortality could inform the ongoing discussions about benefits and risks of screening and case finding.

OBJECTIVES

To define factors associated with undiagnosed obstructive lung disease and its long-term mortality.

METHODS

Cross-sectional analysis of participants, aged 20 to 79 years, in two National Health and Nutritional Examination Surveys (NHANES), NHANES III (1988-1994) and NHANES 2007-2012, with longitudinal follow-up of NHANES III participants.

MEASUREMENTS AND MAIN RESULTS

We classified participants with spirometry-confirmed obstructive disease, based on the fixed ratio definition (FEV1/FVC < 0.7), as "diagnosed" (physician diagnosis of either asthma or chronic obstructive pulmonary disease), and "undiagnosed" (no recorded physician diagnosis). For the longitudinal analysis of NHANES III participants, mortality was the outcome of interest. We tested the contribution of self-reported health status and comorbidity burden (exposure) to the odds of being undiagnosed using logistic models adjusted for demographics, smoking status, and lung function. We estimated hazard ratios (HRs) for all-cause mortality for diagnosed and undiagnosed subjects participating in NHANES III who had spirometry using Cox- proportional regression analysis. Among those with spirometry-defined obstruction, 71.2% (SE, 1.8) in NHANES III and 72.0% (SE, 1.9) in NHANES 2007-2012 were undiagnosed. In multivariate models, undiagnosed obstructive disease was consistently associated in both surveys with self-reported good/excellent health status, lower comorbidity burden, higher lung function, and being of racial/ethnic minority. Among NHANES III participants (median follow up, 14.5 yr), both undiagnosed (HR, 1.23; 95% confidence interval, 1.08-1.40) and correctly diagnosed participants (HR, 1.74; 95% confidence interval, 1.45-2.09) had higher risk for all-cause mortality than participants without obstruction.

CONCLUSIONS

Undiagnosed obstructive lung disease is common among American adults and remained unchanged over 2 decades. Although undiagnosed subjects appear healthier than those with a diagnosis, their risk of death was increased compared with subjects without obstruction. These findings need to be considered when judging the implications of case-finding programs for obstructive lung disease.

Differences in Health-Related Quality of Life Between New Mexican Hispanic and Non-Hispanic White Smokers

BACKGROUND

Smoking is associated with impaired health-related quality of life (HRQL) across all populations. Because decline in lung function and risk for COPD are lower in New Mexican Hispanic smokers compared with their non-Hispanic white (NHW) counterparts, the goal of this study was to ascertain whether HRQL differs between these two racial/ethnic groups and determine the factors that contribute to this difference.

METHODS

We compared the score results of the Medical Outcomes Short-Form 36 Health Survey (SF-36) and St. George's Respiratory Questionnaire (SGRQ) in 378 Hispanic subjects and 1,597 NHW subjects enrolled in the Lovelace Smokers' Cohort (LSC) from New Mexico. The associations of race/ethnicity with SGRQ and SF-36 were assessed by using multivariable regression.

RESULTS

Physical functioning (difference, -4.5; P = .0008) but not mental health or role emotional domains of the SF-36 was worse in Hispanic smokers than in their NWH counterparts in multivariable analysis. SGRQ total score and its activity and impact subscores were worse in Hispanic (vs NHW) smokers after adjustment for education level, current smoking, pack-years smoked, BMI, number of comorbidities, and FEV₁ % predicted (difference range, 2.9-5.0; all comparisons, P ≤ .001). Although the difference in the SGRQ activity domain was above the clinically important difference of four units, the total score was not.

CONCLUSIONS

New Mexican Hispanic smokers have clinically relevant, lower HRQL than their NHW counterparts. A perception of diminished physical functioning and impairment in daily life activities contribute to the poorer HRQL among Hispanic subjects.

Age-Related Differences in Health-Related Quality of Life in COPD: An Analysis of the COPDGene and SPIROMICS Cohorts

OBJECTIVE

Younger persons with COPD report worse health-related quality of life (HRQL) than do older individuals. The factors explaining these differences remain unclear. The objective of this article was to explore factors associated with age-related differences in HRQL in COPD.

METHODS

Cross-sectional analysis of participants with COPD, any Global Initiative for Chronic Obstructive Lung Disease grade of airflow limitation, and ≥ 50 years old in two cohorts: the Genetic Epidemiology of COPD (COPDGene) study and the Subpopulations and Intermediate Outcome Measures in COPD Study (SPIROMICS). We compared St. George's Respiratory Questionnaire (SGRQ) scores by age group: middle-aged (age, 50-64) vs older (age, 65-80) adults. We used multivariate linear modeling to test associations of age with HRQL, adjusting for demographic and clinical characteristics and comorbidities.

RESULTS

Among 4,097 participants in the COPDGene study (2,170 middle-aged and 1,927 older adults) SGRQ total scores were higher (worse) among middle-aged (mean difference, -4.2 points; 95% CI, -5.7 to -2.6; P < .001) than older adults. Age had a statistically significant interaction with dyspnea (P < .001). Greater dyspnea severity (modified Medical Research Council ≥ 2, compared with 0-1) had a stronger association with SGRQ score among middle-aged (β, 24.6; 95% CI, 23.2-25.9) than older-adult (β, 21.0; 95% CI, 19.6-22.3) participants. In analyses using SGRQ as outcome in 1,522 participants in SPIROMICS (598 middle-aged and 924 older adults), we found similar associations, confirming that for the same severity of dyspnea there is a stronger association with HRQL among younger individuals.

CONCLUSIONS

Age-related differences in HRQL may be explained by a higher impact of dyspnea among younger subjects with COPD.

TRIAL REGISTRY

ClinicalTrials.gov; No.: NCT00608764 and No.: NCT01969344; URL: www.clinicaltrials.gov.