Misclassification and characterization of exposure to humidifier disinfectants using a questionnaire

Association between humidifier disinfectant use and development of lung cancer: A nested case-cohort study

OBJECTIVE

The outbreak of lung disease among humidifier disinfectants (HDs) users lead to the identification of humidifier disinfectants-associated lung injury (HDLI) cases. Subsequent research highlighted the respiratory health risks associated HDs but the connection to lung cancer remained uncertain. To assess the risk of lung cancer development among individuals exposed to HDs and to investigate the characteristics of HDs exposure influencing the occurrence of lung cancer.

MATERIALS AND METHODS

A cohort study was conducted using the national database, encompassing 7343 claimants exposed to HDs. The study focused on 195 confirmed lung cancer cases, employing the standardized incidence ratio (SIR) for comparisons with the general population, and the odds ratio (OR) using propensity score matching for internal comparisons.

RESULTS

The study found a significantly higher incidence of lung cancer among individuals exposed to HDs compared to the general Korean population, with elevated SIRs observed in both men and women (SIR = 3.43, 95 % CI = 2.81-4.13 for men; SIR = 11.19, 95 % CI = 8.95-13.82 for women). In the propensity score-matched case-control design, a longer duration of HDs use was associated with an increased risk of lung cancer (OR = 2.48, 95 % CI = 1.35-4.56 for using HDs for more than 49 months and OR = 1.02, 95 % CI = 1.01 - 1.03 for every one month).

CONCLUSION

The findings suggest a potential association between HDs exposure and an increased risk of lung cancer.

Is Polyhexamethylene Guanidine and Oligo(2-(2-Ethoxy) Ethoxyethyl Guanidium Chloride Exposure Related to Gestational Diabetes?

This study aims to investigate the association between exposure to toxic indoor chemicals, specifically polyhexamethylene guanidine (PHMG) and oligo(2-(2-ethoxy) ethoxyethyl guanidinium) chloride (PGH), used in humidifier disinfectants, and gestational diabetes mellitus (GDM). We confirmed pregnancy from 2003 to 2017 and identified GDM by linking a cohort of claimants who reported exposure to PHMG/PGH with National Health Insurance Service data. The GDM incidence was calculated, and PHMG/PGH exposure characteristics-exposure status, the humidifier's distance/location, and exposure duration/hours-were investigated. Logistic regression and mediation analysis were applied using asthma, frequently treated with steroids, as a mediator. Among 521 pregnancies, 38 were identified as GDM, with 2.4% before exposure and 8.9% after exposure. Pregnancies after exposure had a higher odds ratio (OR) for GDM (OR 2.968, 95% CI: 1.004-12.725). A trend of increased GDM risk was observed with longer exposure duration/hours. Additionally, pregnancies after exposure demonstrated total and direct effects on GDM (β = 0.0435, p = 0.036, β = 0.0432, p = 0.030) independent of the indirect effects by asthma. The incidence of GDM was higher after PHMG/PGH exposure compared to before. PHMG/PGH exposure was associated with GDM, independent of asthma. Further research is warranted to confirm these findings in exposed cohorts and to explore the underlying mechanisms.

A Digital Smartphone-Based Self-administered Tool (R+ Dietitian) for Nutritional Risk Screening and Dietary Assessment in Hospitalized Patients With Cancer: Evaluation and Diagnostic Accuracy Study

BACKGROUND

Malnutrition is a common and severe problem in patients with cancer that directly increases the incidence of complications and significantly deteriorates quality of life. Nutritional risk screening and dietary assessment are critical because they are the basis for providing personalized nutritional support. No digital smartphone-based self-administered tool for nutritional risk screening and dietary assessment among hospitalized patients with cancer has been developed and evaluated.

OBJECTIVE

This study aims to develop a digital smartphone-based self-administered mini program for nutritional risk screening and dietary assessment for hospitalized patients with cancer and to evaluate the validity of the mini program.

METHODS

We have developed the R+ Dietitian mini program, which consists of 3 parts: (1) collection of basic information of patients, (2) nutritional risk screening, and (3) dietary energy and protein assessment. The face-to-face paper-based Nutritional Risk Screening (NRS-2002), the Patient-Generated Subjective Global Assessment Short Form (PG-SGA-SF), and 3 days of 24-hour dietary recall (3d-24HRs) questionnaires were administered according to standard procedure by 2 trained dietitians as the reference methods. Sensitivity, specificity, positive predictive value, negative predictive value, κ value, and correlation coefficients (CCs) of nutritional risk screened in R+ Dietitian against the reference methods, as well as the difference and CCs of estimated dietary energy and protein intakes between R+ Dietitian and 3d-24HRs were calculated to evaluate the validity of R+ Dietitian.

RESULTS

A total of 244 hospitalized patients with cancer were recruited to evaluate the validity of R+ Dietitian. The NRS-2002 and PG-SGA-SF tools in R+ Dietitian showed high accuracy, sensitivity, and specificity (77.5%, 81.0%, and 76.7% and 69.3%, 84.5%, and 64.5%, respectively), and fair agreement (κ=0.42 and 0.37, respectively; CC 0.62 and 0.56, respectively) with the NRS-2002 and PG-SGA-SF tools administered by dietitians. The estimated intakes of dietary energy and protein were significantly higher (P<.001 for both) in R+ Dietitian (mean difference of energy intake: 144.2 kcal, SD 454.8; median difference of protein intake: 10.7 g, IQR 9.5-39.8), and showed fair agreement (CC 0.59 and 0.47, respectively), compared with 3d-24HRs performed by dietitians.

CONCLUSIONS

The identified nutritional risk and assessment of dietary intakes of energy and protein in R+ Dietitian displayed a fair agreement with the screening and assessment conducted by dietitians. R+ Dietitian has the potential to be a tool for nutritional risk screening and dietary intake assessment among hospitalized patients with cancer.

TRIAL REGISTRATION

Chinese Clinical Trial Registry ChiCTR1900026324; https://www.chictr.org.cn/showprojen.aspx?proj=41528.

Characterizing Subjects Exposed to Humidifier Disinfectants Using Computed-Tomography-Based Latent Traits: A Deep Learning Approach

Around nine million people have been exposed to toxic humidifier disinfectants (HDs) in Korea. HD exposure may lead to HD-associated lung injuries (HDLI). However, many people who have claimed that they experienced HD exposure were not diagnosed with HDLI but still felt discomfort, possibly due to the unknown effects of HD. Therefore, this study examined HD-exposed subjects with normal-appearing lungs, as well as unexposed subjects, in clusters (subgroups) with distinct characteristics, classified by deep-learning-derived computed-tomography (CT)-based tissue pattern latent traits. Among the major clusters, cluster 0 (C0) and cluster 5 (C5) were dominated by HD-exposed and unexposed subjects, respectively. C0 was characterized by features attributable to lung inflammation or fibrosis in contrast with C5. The computational fluid and particle dynamics (CFPD) analysis suggested that the smaller airway sizes observed in the C0 subjects led to greater airway resistance and particle deposition in the airways. Accordingly, women appeared more vulnerable to HD-associated lung abnormalities than men.

Health Effects Associated With Humidifier Disinfectant Use: A Systematic Review for Exploration

BACKGROUND

It has been 10 years since the outbreak of lung disease caused by humidifier disinfectants in Korea, but the health effects have not yet been summarized. Therefore, this study aims to systematically examine the health effects of humidifier disinfectants that have been discovered so far.

METHODS

All literature with humidifier disinfectants and their representative components as the main words were collected based on the web, including PubMed, Research Information Sharing Service, and government publication reports. A total of 902 studies were searched, of which 196 were selected. They were divided into four groups: published human studies (group 1), published animal and cytotoxicology studies (group 2), technical reports (group 3), and gray literature (group 4).

RESULTS

Out of the 196 studies, 97 (49.5%) were published in peer-reviewed journals as original research. Group 1 consisted of 49 articles (50.5%), while group 2 consisted of 48 articles (49.5%). Overall, respiratory diseases such as humidifier disinfectant associated lung injury, interstitial lung disease, and asthma have a clear correlation, but other effects such as liver, heart, thymus, thyroid, fetal growth, metabolic abnormalities, and eyes are observed in toxicological experimental studies, but have not yet been identified in epidemiologic studies.

CONCLUSION

The current level of evidence does not completely rule out the effects of humidifier disinfectants on extrapulmonary disease. Based on the toxicological evidence so far, it is required to monitor the population of humidifier disinfectant exposure continuously to see if similar damage occurs.