Racial differences in comorbidity profile among patients with chronic obstructive pulmonary disease

Association between reproductive lifespan and lung function among postmenopausal women

Correspondence to: Hye Yun Park, MD, PhD. Division of Pulmonary and Critical Care Medicine, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Gangnam-gu, Seoul, 06351, South Korea. Email: hyeyunpark@skku.edu; Juhee Cho, PhD. Department of Clinical Research Design and Evaluation, SAIHST, Sungkyunkwan University, 81 Irwon-ro, Gangnam-gu, Seoul, 06351, South Korea. Email: Jcho@skku.edu.

An analysis of the relationship between chronic obstructive pulmonary disease, smoking and depression in an integrated healthcare system

OBJECTIVE

Chronic Obstructive Pulmonary Disease (COPD) and smoking are highly associated with depression and hypoxia. There is limited knowledge about whether hypoxic conditions interact to cause depression.

METHOD

A population-based cohort study was conducted using the Veterans Affairs (VA) Corporate Data Warehouse. Patients must have accessed any healthcare at a VA facility between 2004 and 2014 and had a negative depression screen (Patient Health Questionnaire-2 (PHQ-2) score ≤ 2). Patients with COPD or a positive depression screen (PHQ-2 score: 3+) during or prior to the year with a negative depression screen were excluded. Logistic regression with annual observations was used to evaluate depression incidence based on COPD and smoking status. Models were adjusted for demographics and other comorbid conditions. A probability scale was used to examine interactions between COPD and smoking.

RESULTS

A total of 3,284,496 patients were included. Patients with COPD and current smokers were at increased risk for developing depression. There were minimal interaction effects between COPD and smoking. The odds of developing depression in a year varied from 1.4% among never smokers without COPD to 2.9.% among current smokers with COPD.

CONCLUSION

Smoking and COPD are independent risk factors for depression and interact to cause depression. Further research is needed to confirm whether hypoxia contributes to this association.

Sleep Duration and Efficiency Associated With Better Functional Exercise Capacity in Black Smokers at Risk for COPD

BACKGROUND

Black smokers have earlier development of lung disease as well as poorer sleep health than whites.

RESEARCH QUESTION

In a sample of black smokers, to what extent does sleep health modify the association between smoking level and functional exercise capacity?

DESIGN AND METHODS

Cross-sectional data from 209 black smokers (≥ 1 cigarette in last month), aged 40 to 65 years with no evidence of sleep-disordered breathing (apnea-hypopnea index < 15) or severe COPD (FEV₁ > 50%), were used for the current study. Self-reported smoking rate, objectively measured sleep efficiency (SE), total sleep time (TST), and the 6-min walk test (6MWT) for functional exercise capacity were the key assessments.

RESULTS

The mean age was 54.8 years (SD, 5.96), and mean cigarettes smoked per day (cpd) was 8.71 (SD, 6.78). Mean SE was 69.9% (SD, 12.3%), and mean TST was 307.99 min (SD 92.2). In adjusted linear regression models of the 6MWT (meters), TST (slope estimate, -0.14; P = .14) and SE (slope estimate, -1.0; P = .19) were negatively associated with 6MWT. The smoking rate × SE interaction was highly significant (slope estimate, 0.18; P = .007) such that in individuals who smoked ≥ 10 cpd, every additional percentage of SE garnered an additional distance of 0.83 to 6.62 m. Similarly, the smoking rate × TST interaction was significant (slope estimate, 0.019; P = .03) such that in smokers who smoked ≥ 10 cpd, every additional minute of TST garnered an additional distance of 0.04 to 0.60 m.

INTERPRETATION

Higher SE and, to a lesser extent, longer TST, in black adults who smoke ≥ 10 cpd is associated with better 6MWT performance.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov; No.: NCT03534076; URL: www.clinicaltrials.gov.

Risk factors for early readmission after acute exacerbation of chronic obstructive pulmonary disease

BACKGROUND AND AIMS

Patients discharged after treatment for acute exacerbation of chronic obstructive pulmonary disease (COPD) are at high risk for readmission. We aimed to identify the prevalence and risk factors for readmission.

METHODS

We included 16,105 patients who had claimed their medical expenses from 1 May 2014 to 1 May 2016 after discharge from any medical facility in Korea, following treatment for acute exacerbation of COPD. We analysed the potential risk factors for readmission within 30 days of discharge.

RESULTS

Readmission rate was 26.4% (3989 patients among 15,101 patients) and over 50% of readmissions occurred within 10 days of discharge. Approximately 57% of readmissions occurred due to respiratory causes. Major causes of readmission were COPD (27%), pneumonia (14.2%), and lung cancer (7.1%), in that order. Patients who were readmitted were male, had more comorbidities and were less frequently admitted to tertiary hospitals than those who were not readmitted. Risk factors for readmission within 30 days of discharge were male sex, medical aid coverage, longer hospital stay, longer duration of systemic steroid use during hospital stay, high comorbid condition index, and discharge to skilled nursing facility.

CONCLUSION

Readmission occurred in approximately one-quarter of patients, and was associated with patient-related and clinical factors. Using these results, we can identify high-risk patients for readmission and precautions are needed to be taken before deciding on a discharge plan. Further research is needed to develop accurate tools for predicting the risk of readmission before discharge, and development and evaluation of an effective care programme for COPD patients are necessary.The reviews of this paper are available via the supplemental material section.

The disease burden of bronchiectasis in comparison with chronic obstructive pulmonary disease: a national database study in Korea

Background

The prevalence and disease burden of bronchiectasis in comparison to those of chronic obstructive pulmonary disease (COPD) have not been well elucidated using a nationally representative database.

Methods

We compared respiratory symptoms, physical activity, quality of life, and socioeconomic status in subjects with bronchiectasis versus those with COPD or control subjects participating in the Korea National Health and Nutrition Examination Survey 2007-2009. Participants were classified as physician-diagnosed bronchiectasis, COPD, and control (those without COPD or bronchiectasis).

Results

The prevalence of bronchiectasis in subjects aged 40 years or older was 0.8%. Compared to COPD subjects, bronchiectasis subjects were more likely to be younger (mean 59.0 years, P<0.001), female (47.6%, P<0.001), and never-smoker (50.1%, P<0.001) and have had history of pulmonary tuberculosis (40.5%, P<0.001) and osteoporosis (19.1%, P=0.025). However, as in COPD subjects, bronchiectasis subjects had low family income (P<0.001) and the proportion of subjects working as manager/professional/office workers (6.4%, P<0.001) was smaller than that of control subjects. After adjusting for covariables, compared to control, bronchiectasis subjects but not COPD subjects were more likely to have respiratory symptoms [adjusted odds ratio (OR) =7.96, 95% confidence interval (CI): 2.10-30.12], limitation in physical activity (adjusted OR =9.43, 95% CI: 1.06-83.79), and low family income (adjusted OR =3.61, 95% CI: 1.75-7.47).

Conclusions

The prevalence of bronchiectasis in subjects at least 40 years of age was 0.8% in Korea. Despite large number of young patients and low prevalence of smoking history, respiratory symptoms, limitation in physical activity, and low family income were significant burden in bronchiectasis subjects.

Impact of chronic obstructive pulmonary disease on mortality: A large national cohort study

BACKGROUND AND OBJECTIVE

The global burden of chronic obstructive pulmonary disease (COPD) is increasing and COPD patients are at higher risk for all-cause mortality. We aimed to evaluate the impact of COPD on specific-cause mortality using national data.

METHODS

This was nationwide retrospective cohort study of 340, 767 adults aged 40-84 years who lacked COPD diagnosis at baseline between 1 January 2003 and 31 December 2013. Incident COPD was defined by reference to COPD claim codes and prescription of COPD medication at least twice annually. Cox proportional hazard ratio (HR) for each cause of death in the COPD group was compared to that of the non-COPD group, with other causes of death accounted as the competing risk.

RESULTS

All-cause mortality was higher in the COPD (2,978 per 100, 000 person-years) than the non-COPD group (629 per 100, 000 person-years) and adjusted HR was 1.41 (95% CI = 1.32, 1.50). The association was particularly strong for chronic lower airway disease (adjusted sub-HR = 9.67; 95% CI = 7.21, 12.96) and lung cancer (adjusted sub-HR = 3.16; 95% CI = 2.68, 3.71), and the association was stronger in those aged <60 years.

CONCLUSION

In this large national cohort, COPD patients were at a statistically significant higher risk for all-cause mortality than those without COPD. They were more likely to die from chronic lower airway disease, lung cancer and pneumonia than subjects without COPD. The impact of COPD on specific mortalities was stronger in younger subjects.

The impact of low forced vital capacity on behavior restrictions in a population with airflow obstruction

Background

Recent studies have suggested that low forced vital capacity (FVC) is related to respiratory symptoms with various comorbid conditions that eventually lead to physical inactivity and may be applied to subjects with airflow obstruction (AO). Therefore, this study aimed to evaluate the association between low FVC and behavior restrictions in subjects with AO.

Methods

A cross-sectional study was performed using data from the Korea National Health and Nutrition Survey conducted between 2007 and 2015. Participants aged 40 to 79 years with spirometry-defined AO (pre-bronchodilator forced expiratory volume in one second/FVC <70%) were analyzed to evaluate the association between low FVC (defined as FVC <80% predicted) and behavior restrictions.

Results

A total of 3,345 participants with AO were included. The proportion of subjects with low FVC varied widely according to severity of airflow limitation (0.9%, 35.5%, and 85.1% in the mild, moderate, and severe-to-very-severe AO groups, respectively). Compared to the moderate AO group with normal FVC, those with low FVC were more likely to be older, to be never- or ex-smokers, to have larger waist size with higher body mass index, and to have comorbidities such as diabetes, hypertension, dyslipidemia, and osteoporosis. Low FVC was independently associated with behavior restrictions [adjusted prevalence ratio (aPR), 1.72; 95% confidence interval (CI), 1.43-2.06] among all participants with AO, and this was most prominent in those with moderate AO (aPR, 1.65; 95% CI, 1.27-2.13).

Conclusions

In subjects with moderate AO, low FVC was independently associated with behavior restrictions even after adjusting for confounding factors.

Osteoporosis among Patients with Chronic Obstructive Pulmonary Disease: Systematic Review and Meta-analysis of Prevalence, Severity, and Therapeutic Outcomes

Chronic obstructive pulmonary disease (COPD) can be associated with systemic inflammatory trademarks and can coexist with other chronic debilitating diseases such as osteoporosis, which is considered among the most serious comorbidities of COPD. In this review, we aimed at finding answers for the following questions and tried to encapsulate the available literature: (1) how prevalent is osteoporosis among patients with COPD? (2) What are severity patterns of osteoporosis in case of COPD? (3) What are the therapeutic outcomes for patients with osteoporotic COPD? The total number of patients with COPD from all studies was 3815, majority of which were male (2658) representing 69.67% of patients. The mean ± standard deviation for percentage of forced expiratory volume in 1s (FEV1%) was 55.43 ± 14.62%, body mass index for almost 91.29% of patients was 24.4 ± 4.45 kg/m², whereas fat-free mass index (FFMI) was 17 ± 0.93 kg/m² for 17.66%. The percentage of patients with COPD having osteoporosis varied in the analyzed studies from 14% up to 66.6%. The mean prevalence of reported osteopenia from 14 studies (n = 2107) was 39.91%, whereas for osteoporosis, the mean prevalence was 37.62% for all included studies. Osteoporosis was highly prevalent among patients with COPD. It is reasonable to call for osteoporosis screening in patients with COPD who are above 65 years, in advanced stages, with BMI lower than 21 kg/m² or with FFMI lower than 16 kg/m² for males and 15 kg/m² for females. There is a lack of research investigating severity and treatments of osteoporosis in patients with COPD.