VitalQPlus: a potential screening tool for early diagnosis of COPD

Association between lung function impairment with urinary heavy metals in a community in Klang Valley, Malaysia

Lung function status can be directly or indirectly affected by exposure to pollutants in the environment. Urinary heavy metals may be an indirect indicator of lung function impairment that leads to various diseases such as chronic obstructive pulmonary disease (COPD). This study aimed to explore the prevalence of lung function impairment as well as its association with urinary heavy metal levels and other influencing factors among the community in Klang Valley, Malaysia. Urinary sampling was done during various community events in the housing areas of Klang Valley between March and October 2019. Only respondents who consented would undergo a lung function test. Urine samples were obtained and sent for Inductively Coupled Plasma Mass Spectrometry (ICP-MS) analysis for heavy metal cadmium (Cd) and lead (Pb) concentration. Of the 200 recruited respondents, 52% were male and their ages ranged from 18 years old to 74 years old with a mean age of 38.4 ± 14.05 years. Urinary samples show high urinary Cd level in 12% of the respondents (n = 24) whereas none recorded a high urinary Pb level. There was a positive correlation between the levels of urinary Cd and urinary Pb (r = 0.303; p = 0.001). Furthermore, a negative correlation was detected between urinary Cd level and forced vital capacity (FVC) (r =  - 0.202, p = 0.004), force expiratory volume at the first second (FEV1) (r =  - 0.225, p = 0.001), and also force expiratory flow between 25-75% of FVC (FEF 25-75%) (r =  - 0.187, p = 0.008). However, urinary Pb did not show any correlation with lung function parameters. Multiple linear regression analysis showed that urinary Cd had a significant negative effect on FVC (p = 0.025) and FEV1 (p = 0.004) based on the predicted value. Additionally, other factors such as education level (p = 0.013) also influenced lung function. However, no interaction was detected between heavy metals or other factors. In short, there was a significant negative linear relationship between urinary Cd and lung function, whereas urinary Pb was not associated with lung function. Beside acting as a biomarker for cadmium exposure level, urinary Cd may also be applied as indirect biomarker for asymptomatic chronic lung function deterioration among the healthy population.

Performance and Clinical Utility of Various Chronic Obstructive Pulmonary Disease Case-Finding Tools

BACKGROUND AND AIM

Chronic obstructive pulmonary disease (COPD) is frequently underdiagnosed because of the unavailability of spirometers, especially in resource-limited outpatient settings. This study provides real-world evidence to identify optimal approaches for COPD case finding in outpatient settings.

METHODS

This retrospective study enrolled individuals who were at risk of COPD (age ≥40 years, ≥10 pack-years, and ≥1 respiratory symptom). Eligible participants were examined using various COPD case-finding tools, namely the COPD Population Screener (COPD-PS) questionnaire, a COPD prediction (PCOPD) model, and a microspirometer, Spirobank Smart; subsequently, the participants underwent confirmatory spirometry. The definition and confirmation of COPD were based on conventional spirometry. Receiver operating characteristic curve (ROC), area under the curve (AUC), and decision curve analyses were conducted, and a clinical impact curve was constructed.

RESULTS

In total, 385 participants took part in the study [284 without COPD (73.77%) and 101 with COPD (26.23%)]. The microspirometer exhibited a higher AUC value than did the COPD-PS questionnaire and the PCOPD model. The AUC for microspirometry was 0.908 (95% confidence interval [CI] = 0.87-0.95), that for the PCOPD model was 0.788 (95% CI = 0.74-0.84), and that for the COPD-PS questionnaire was 0.726 (95% CI = 0.67-0.78). Decision and clinical impact curve analyses revealed that a microspirometry-derived FEV1/FVC ratio of <74% had superior clinical utility to the other measurement tools.

CONCLUSION

The PCOPD model and COPD-PS questionnaire were useful for identifying symptomatic patients likely to have COPD, but microspirometry was more accurate and had higher clinical utility. This study provides real-world evidence to identify optimal practices for COPD case finding; such practices ensure that physicians have convenient access to up-to-date evidence when they encounter a symptomatic patient likely to have COPD.

Performance of COPD population screener questionnaire in COPD screening: a validation study and meta-analysis

This study aimed to validate the chronic obstructive pulmonary disease (COPD) Population Screener (COPD-PS) questionnaire as a screening tool in a cohort of Chinese subjects who underwent a health examination, and to summarise its overall performance through a meta-analysis. We enrolled 997 subjects aged ≥40 years who underwent a health examination, both lung function and COPD-PS data were collected. The screening performance of COPD-PS was evaluated with a receiver operating characteristic (ROC) curve analysis, using the area under the curve (AUC) to assess the screening accuracy. A standard diagnostic meta-analysis was used to summarise the screening performance of COPD-PS for COPD. Of the 997 subjects, 157 were identified as having COPD. The COPD-PS score was significantly higher in COPD patients than controls (5.03 ± 5.11 vs. 2.72 ± 1.80, p < .001). At a cut-off of 4, the sensitivity and specificity of COPD-PS for identifying COPD were 74.52 and 70.24%, respectively, with an AUC of 0.79. Eight studies (including this study) were included in this meta-analysis. The pooled estimates for COPD-PS were as follows: sensitivity of 0.66 (95% CI: 0.47-0.63), specificity of 0.86 (95% CI: 0.84-0.89), positive likelihood ratio of 3.00 (95% CI: 1.65-5.47), negative likelihood ratio of 0.43 (95% CI: 0.35-0.52) and diagnostic odds ratio of 7.24 (95% CI: 3.91-13.40). The AUC of the summary ROC curve was 0.78. COPD-PS appears to be a useful tool for screening individuals with a high risk of COPD and guiding the selection of individuals for subsequent spirometry examination.KEY MESSAGESCOPD-PS is a simple and useful method to screen COPD.The combination of COPD-PS with other tools may improve the screen performance.

Forced oscillation technique for early detection of the effects of smoking and COPD: contribution of fractional-order modeling

Purpose

The aim of the present study was to evaluate the performance of the forced oscillation technique (FOT) for the early diagnosis of the effects of smoking and COPD. The contributions of the integer-order (InOr) and fractional-order (FrOr) models were also evaluated.

Patients and methods

In total, 120 subjects were analyzed: 40 controls, 40 smokers (20.3±9.3 pack-years) and 40 patients with mild COPD.

Results

Initially, it was observed that traditional FOT parameters and the InOr and FrOr models provided a consistent description of the COPD pathophysiology. Mild COPD introduced significant increases in the FrOr inertance, damping factor and hysteresivity (P<0.0001). These parameters were significantly correlated with the spirometric parameters of central and small airway obstruction (P<0.0001). The diagnostic accuracy analyses indicated that FOT parameters and InOr modeling may adequately identify these changes (area under the receiver operating characteristic curve – AUC >0.8). The use of FrOr modeling significantly improved this process (P<0.05), allowing the early diagnosis of smokers and patients with mild COPD with high accuracy (AUC >0.9).

Conclusion

FrOr modeling improves our knowledge of modifications that occur in the early stages of COPD. Additionally, the findings of the present study provide evidence that these models may play an important role in the early diagnosis of COPD, which is crucial for improving the clinical management of the disease.

Quit rates at 6 months in a pharmacist-led smoking cessation service in Malaysia

BACKGROUND

Smoking cessation clinics have been established in Malaysia since 2004, but wide variations in success rates have been observed. This study aimed to evaluate the proposed pharmacist-led Integrated Quit Smoking Service (IQSS) in Sabah, Malaysia, and identify factors associated with successful smoking cessation.

METHODS

Data from 176 participants were collected from one of the quit-smoking centres in Sabah, Malaysia. Pharmacists, doctors and nurses were involved throughout the study. Any health care provider can refer patients for smoking cessation, and free pharmacotherapy and counselling was provided during the cessation period for up to 3 months. Information on demographic characteristics, smoking behaviours, follow-up and pharmacotherapy were collected. The main outcome measure was the abstinence from smoking, which was verified through carbon monoxide in expired air during the 6-month follow-up.

RESULTS

A 42.6% success rate was achieved in IQSS. Smoking behaviour such as lower cigarette intake and lower Fagerström score were identified as factors associated with success. On top of that, a longer duration of follow-up and more frequent visits were significantly associated with success in quitting smoking.

CONCLUSION

Collaboration among health care practitioners should be the main focus, and we need a combination of proven effective modalities in order to create an ideal smoking cessation module.