Medical physics practice guideline 4.b: Development, implementation, use and maintenance of safety checklists.

The American Association of Physicists in Medicine (AAPM) is a nonprofit professional society whose primary purposes are to advance the science, education, and professional practice of medical physics. The AAPM has more than 8000 members and is the principal organization of medical physicists in the US. The AAPM will periodically define new practice guidelines for medical physics practice to help advance the science of medical physics and to improve the quality of service to patients throughout the US. Existing medical physics practice guidelines will be reviewed for the purpose of revision or renewal, as appropriate, on their fifth anniversary or sooner. Each medical physics practice guideline represents a policy statement by the AAPM, has undergone a thorough consensus process in which it has been subjected to extensive review, and requires the approval of the Professional Council. The medical physics practice guidelines recognize that the safe and effective use of diagnostic and therapeutic radiology requires specific training, skills, and techniques, as described in each document. Reproduction or modification of the published practice guidelines and technical standards by those entities not providing these services is not authorized. The following terms are used in the AAPM practice guidelines: Must and must not: Used to indicate that adherence to the recommendation is considered necessary to conform to this practice guideline. While must is the term to be used in the guidelines, if an entity that adopts the guideline has shall as the preferred term, the AAPM considers that must and shall have the same meaning. Should and should not: Used to indicate a prudent practice to which exceptions may occasionally be made in appropriate circumstances.

Perceptions of Attractiveness in Dorsal Aesthetic Lines of the Nose: A Crowd Sourcing Analysis.

Background: Some surgeons have recently advocated for a fusiform pattern with a flare around the keystone area over the more traditional straight/curvilinear shape for the ideal shape of the nasal dorsal aesthetic lines (DALs). Objective: To compare the lay persons judgment of what constitutes an ideal nasal dorsum outline. Methods: An observational crowdsourcing survey-based study was designed and conducted by the authors to determine how the public viewed these two nasal dorsum aesthetic configurations. In total, 1034 surveys comparing various altered images with these variants were analyzed. Results: Our crowd-based cohort preferences for DALs favored as more attractive, the traditional concept of paired straight or curvilinear lines sweeping gently from the glabella to the nasal tip. The fusiform nose was seen as more natural. Conclusion: Our study suggests that individuals may view a straight/curvilinear nasal dorsum as a more attractive result, whereas a fusiform nasal dorsum may be viewed as a more natural result.

Pediatric Odontogenic and Maxillofacial Bone Pathology: A Global Analysis.

BACKGROUND: Although pathology in the maxillary and mandibular bones is rare in young patients, the differential diagnosis is broad. The World Health Organization (WHO) updated its classification of maxillofacial bone pathology in 2017. Using these updated guidelines, a systematic review of common maxillofacial bone lesions in the pediatric population was performed. METHODS: A PubMed search was conducted capturing English language articles from inception to July 2020. Thirty-one articles were identified that described the frequency of maxillofacial bone pathology. Data were extracted and organized using the WHO 2017 classification of odontogenic and maxillofacial bone tumors. Prevalence data were analyzed among diagnostic categories and geographical regions. The SAS version 9.4 was used to complete statistical analyses. RESULTS: The articles included patients from birth to a maximum age of 14 to 19 years. The most common odontogenic cysts included radicular cyst (42.7%) and dentigerous cyst (39.0%) followed by odontogenic keratocyst (15.0%). Among odontogenic bone tumors, odontoma (49.3%) was most common followed by ameloblastoma (29.1%). The most common nonodontogenic bone tumor was fibrous dysplasia (42.4%), and the most common malignant bone tumor was osteosarcoma (75.0%). Significant variations were found by geographic region, with dentigerous cyst more common than radicular cyst, and ameloblastoma more common than odontoma in African and Asian countries (P < 0.0001). CONCLUSIONS: This systematic review uses the WHO 2017 guidelines to classify common odontogenic and nonodontogenic maxillofacial bone lesions around the world. Pathogenesis, presentation, and available treatment options for the most common maxillofacial bone lesions are reviewed.

Cartilage Grafting Outcomes in Intermediate and Definitive Cleft Rhinoplasty.

OBJECTIVE: To compare cartilage grafting outcomes in intermediate versus definitive cleft rhinoplasty. DESIGN: A retrospective chart review was conducted. The χ2 and Fisher exact tests were used for statistical analyses. Results were considered statistically significant at P < .05. PARTICIPANTS: All subjects who underwent revision cleft rhinoplasties between July 2011 and June 2019 were included. Subjects with syndromic conditions were excluded. RESULTS: A total of 46 subjects with a cleft nose deformity underwent 65 rhinoplasty procedures. The ages averaged 17 years (range 5-50) with 34 (73.9%) males and 12 (26.1%) females. In the intermediate group, 6 (28.6%) subjects required cartilage grafting as part of 6 cleft rhinoplasties, whereas 15 (71.4%) subjects underwent a total of 26 cleft rhinoplasties that did not require grafting. In the definitive group, 18 (76%) subjects required cartilage grafting over 21 cleft rhinoplasties, whereas 7 (24%) subjects underwent a total of 9 cleft rhinoplasties where cartilage grafting was not required. The difference between the number of subjects requiring cartilage grafting in the intermediate versus the definitive group was statistically significant (P = .007). Ear concha and nose were the most frequently used cartilage donor sites, with no observed complications. CONCLUSIONS: Cartilage grafting was significantly more common in the definitive rhinoplasty group. Intermediate cleft rhinoplasty during the 5- to 13-year age period was effective, with a low-risk profile. In our experience, ear concha and nose were the preferred cartilage donor sites, with effective results and an excellent safety profile.

Dissemination of Evidence-Based School Asthma Management Programs: Piloting Asthma 411 in an Urban Texas School District.

BACKGROUND: The dissemination and implementation (D&I) of evidence-based initiative (EBIs) is critical to improved public health. The Asthma 411 EBI was piloted in Texas from 2013 to 2015. The pilot's evaluation assessed its effectiveness and identified approaches to support D&I of school-health EBIs. METHODS: The pilot study was conducted in two schools; service categories included: a consulting physician, enhanced school asthma services, and support for links to community health resources. Data was collected on Emergency Medical Service (EMS) calls, aggregated nursing services, demographic characteristics, availability of medication provided through existing policies, and informal interviews. RESULTS: During the pilot, school-day asthma-related Emergency Medical Service (EMS) calls were eliminated. Documented asthma self-management education, authorization for rescue medication, and efforts to communicate with parents and health providers increased. Between year-1 and year-2, the gap between unadjusted, weighted mean absences among students with and without asthma was reduced by 1.1 days. However, this difference was not seen in a fully adjusted negative, binomial regression model. CONCLUSIONS: Evaluation of the Asthma 411 pilot suggests many EBI benefits were retained and identifies factors that may facilitate D&I of school health EBIs. Future research will clarify impacts on absenteeism and determine if observed benefits are sustained.

3D printed copper-plastic composite material for use as a radiotherapy bolus.

The purpose of this work is to evaluate a commercially available copper-plastic composite material for use as a custom fit 3D printed bolus. Superficial dose under copper-plastic composite bolus was assessed for 0.4 mm, 0.6 mm, and 0.8 mm thicknesses. Superficial dose measurements were performed with an Attix parallel plate ionization chamber and radiochromic film. Additionally, a custom-fit bolus was designed for the temporal-frontal cranial region of an anthropomorphic phantom. A treatment plan with a tangential field arrangement was designed, and radiochromic film was used to measure the dose enhancement to the surface of the phantom from the bolus and compared to the calculated dose. It was shown that 3D printed copper-plastic composite bolus can provide the equivalent dose enhancement of thicker conventional bolus. Due to the limited thickness of the copper-plastic composite the bolus can remain flexible, which can aid in the placement of the bolus and improve patient comfort.

Happiness in Plastic Surgery: A Cross-Sectional Analysis of 595 Practicing Plastic Surgeons, Fellows, Residents, and Medical Students.

BACKGROUND: Despite a heightened appreciation for wellness in medicine, there exists little information specific to plastic surgery. The purpose of this research was to assess happiness within the field of plastic surgery. METHODS: A cross-sectional study was conducted in July of 2017 by distributing an American Society of Plastic Surgeons sponsored survey to a random cohort of current practicing American Society of Plastic Surgeons members, residents and fellows. In addition, the same survey was sent to medical students applying to integrated plastic surgery residency. Total happiness scores (Subjective Happiness Scale) were averaged and compared between and within surveyed groups. RESULTS: A total of 595 individuals completed surveys, including 287 practicing surgeons, 116 residents, 12 fellows, and 180 medical students. Differences in happiness scores between the groups were statistically significant (P < 0.01). For practicing physicians, happiness scores were significantly greater for those more than 20 years out from training (P < 0.01). Furthermore, a significantly positive correlation was found between practice expectations coming out of residency and happiness scores (Pearson correlation coefficient, 0.2; P < 0.01). CONCLUSIONS: Despite the prevalence of burnout and mental health disorders associated with a career in medicine, plastic surgeons and trainees report high levels of happiness. Practicing plastic surgeons report increased happiness further out from training and when meeting practice expectations coming out of training. Otherwise, there were no significant differences in happiness between groups. Regarding sex, it is encouraging to report no significant sex discrepancies with happiness in a field where women still face significant adversity.

Using machine learning to examine the relationship between asthma and absenteeism.

In this study, we found that machine learning was able to effectively estimate student learning outcomes geo-spatially across all the campuses in a large, urban, independent school district. The machine learning showed that key factors in estimating the student learning outcomes included the number of days students were absent from school. In turn, one of the most important factors in estimating the number of days a student was absent was whether or not the student had asthma. This highlights the importance of environmental public health for student learning outcomes.

The "Warm Zone" Cases: Environmental Monitoring Immediately Outside the Fire Incident Response Arena by Firefighters.

Hazardous work zones (i.e., hot, warm, and cold) are typically established by emergency response teams during hazardous materials (HAZMAT) calls but less consistently for fire responses to segment personnel and response activities in the immediate geographic area around the fire. Despite national guidelines, studies have documented the inconsistent use of respiratory protective equipment by firefighters at the fire scene. In this case-series report, we describe warm zone gas levels using multigas detectors across five independent fire incident responses all occurring in a large South Florida fire department. Multigas detector data collected at each fire response indicate the presence of sustained levels of volatile organic compounds in the "warm zone" of each fire event. These cases suggest that firefighters should not only implement strategies for multigas detector use within the warm zone but also include respiratory protection to provide adequate safety from toxic exposures in the warm zone.

Residual Isocyanates in Medical Devices and Products: A Qualitative and Quantitative Assessment.

We conducted a pilot qualitative and quantitative assessment of residual isocyanates and their potential initial exposures in neonates, as little is known about their contact effect. After a neonatal intensive care unit (NICU) stockroom inventory, polyurethane (PU) and PU foam (PUF) devices and products were qualitatively evaluated for residual isocyanates using Surface SWYPE™. Those containing isocyanates were quantitatively tested for methylene diphenyl diisocyanate (MDI) species, using UPLC-UV-MS/MS method. Ten of 37 products and devices tested, indicated both free and bound residual surface isocyanates; PU/PUF pieces contained aromatic isocyanates; one product contained aliphatic isocyanates. Overall, quantified mean MDI concentrations were low (4,4'-MDI = 0.52 to 140.1 pg/mg) and (2,4'-MDI = 0.01 to 4.48 pg/mg). The 4,4'-MDI species had the highest measured concentration (280 pg/mg). Commonly used medical devices/products contain low, but measurable concentrations of residual isocyanates. Quantifying other isocyanate species and neonatal skin exposure to isocyanates from these devices and products requires further investigation.

Impact of air quality guidelines on COPD sufferers.

BACKGROUND: COPD is one of the leading causes of morbidity and mortality in both high- and low-income countries and a major public health burden worldwide. While cigarette smoking remains the main cause of COPD, outdoor and indoor air pollution are important risk factors to its etiology. Although studies over the last 30 years helped reduce the values, it is not very clear if the current air quality guidelines are adequately protective for COPD sufferers. OBJECTIVE: This systematic review was to summarize the up-to-date literature on the impact of air pollution on the COPD sufferers. METHODS: PubMed and Google Scholar were utilized to search for articles related to our study's focus. Search terms included "COPD exacerbation", "air pollution", "air quality guidelines", "air quality standards", "COPD morbidity and mortality", "chronic bronchitis", and "air pollution control" separately and in combination. We focused on articles from 1990 to 2015. We also used articles prior to 1990 if they contained relevant information. We focused on articles written in English or with an English abstract. We also used the articles in the reference lists of the identified articles. RESULTS: Both short-term and long-term exposures to outdoor air pollution around the world are associated with the mortality and morbidity of COPD sufferers even at levels below the current air quality guidelines. Biomass cooking in low-income countries was clearly associated with COPD morbidity in adult nonsmoking females. CONCLUSION: There is a need to continue to improve the air quality guidelines. A range of intervention measures could be selected at different levels based on countries' socioeconomic conditions to reduce the air pollution exposure and COPD burden.

Aerosol optical depth as a measure of particulate exposure using imputed censored data, and relationship with childhood asthma hospital admissions for 2004 in athens, Greece.

An understanding of human health implications from atmosphere exposure is a priority in both the geographic and the public health domains. The unique properties of geographic tools for remote sensing of the atmosphere offer a distinct ability to characterize and model aerosols in the urban atmosphere for evaluation of impacts on health. Asthma, as a manifestation of upper respiratory disease prevalence, is a good example of the potential interface of geographic and public health interests. The current study focused on Athens, Greece during the year of 2004 and (1) demonstrates a systemized process for aligning data obtained from satellite aerosol optical depth (AOD) with geographic location and time, (2) evaluates the ability to apply imputation methods to censored data, and (3) explores whether AOD data can be used satisfactorily to investigate the association between AOD and health impacts using an example of hospital admission for childhood asthma. This work demonstrates the ability to apply remote sensing data in the evaluation of health outcomes, that the alignment process for remote sensing data is readily feasible, and that missing data can be imputed with a sufficient degree of reliability to develop complete datasets. Individual variables demonstrated small but significant effect levels on hospital admission of children for AOD, nitrogen oxides (NOx), relative humidity (rH), temperature, smoke, and inversely for ozone. However, when applying a multivari-able model, an association with asthma hospital admissions and air quality could not be demonstrated. This work is promising and will be expanded to include additional years.

Development and evaluation of an integrated asthma awareness curriculum for the elementary school classroom.

Asthma is one of the most common causes of school absenteeism, and many children are affected by, or encounter, it in the school setting. An integrated curriculum that presents asthma as a real world example can raise all children's awareness and understanding of asthma, not just those with the condition. A 15-lesson, asthma-based curriculum was developed to integrate with and enhance the core subjects of math, science, and communication arts. A pilot test was performed in fourth- and fifth-grade classes to assess student asthma knowledge gain, teacher acceptance, and grade appropriateness of the curriculum. During the 2006-2007 school year, 15 teachers were recruited from the St. Louis, MO, USA area to assess the curriculum through teaching and administering pre- and post-unit tests and completing a teacher evaluation for each lesson taught. Four additional classrooms served as comparisons. Paired t tests were used for each lesson taught, to evaluate pre-/post-test and classroom differences, and focus groups were used for qualitative evaluation. There was an increase in asthma knowledge between pre- and post-tests in both grades, individually and combined (p < 0.001). Intervention post-test scores were higher than comparison classroom scores (p < 0.001). Teacher feedback indicated that the lessons enhanced previously learned skills and increased students' overall understanding of asthma. Offering asthma education in the classroom can provide an opportunity for all students to gain asthma knowledge and build health literacy about a leading chronic disease in school-aged children.

COPD is associated with a macrophage scavenger receptor-1 gene sequence variation.

BACKGROUND: Macrophages play an important role in COPD. We genotyped at-risk smokers to evaluate the role of polymorphisms in the macrophage scavenger receptor-1 gene (MSR1) in COPD susceptibility and related measures of lung function. Then, in macrophages from donors with specific MSR1 genotypes, we determined the effect of MSR1 single nucleotide polymorphisms (SNPs) on macrophage function by examining in vitro adhesion, receptor expression, and cell number in culture as an index of increased survival/reduced apoptosis. METHODS: Smokers (> or = 20 pack-years) who were > 40 years (n = 714) were genotyped for seven SNPs; one nonsense change (ex6R293x_C/T), four missense changes (ex4V113A_T/C, ex4P174Y_G/T, ex11H441R_A/G, and in the ligand binding site ex6P275A_C/G), -176511_A/G in the promoter region, and IVS5-59_C/A in the intron. Nonsmoking healthy volunteers (n = 85) were genotyped, and peripheral blood monocytes were isolated from seven P275A_CG/GG and eight P275A_CC controls and cultured to generate monocyte-derived macrophages (MDM). The effectiveness of trypsin and scraping to dislodge MDM was scored on a four-point subjective scale. MDM were counted on a Z1 particle counter and surface expression of MSR1 was determined by fluorescence-activated cell sorting analysis using secondary staining of antibodies against human macrophage scavenger receptor (MSR1). RESULTS: The MSR1-coding SNP P275A was associated with susceptibility to COPD in smokers (P < .005) and a lower percent predicted (pp) FEV(1), FEV(1)/FVC, and pp forced expiratory flow (FEF)(25-75) (P = .03). P275A_CG/GG was also associated with increases in maintenance of cell number in culture (increased survival/reduced apoptosis), MSR1 expression, and adhesion of macrophages to plastic in vitro (P < .05). CONCLUSIONS: The MSR1 association with COPD susceptibility, COPD-related measures of lung function, and abnormalities of macrophage function may account for significant COPD morbidity.

Validity and reliability of an occupational exposure questionnaire for parkinsonism in welders.

This study assessed the validity and test-retest reliability of a medical and occupational history questionnaire for workers performing welding in the shipyard industry. This self-report questionnaire was developed for an epidemiologic study of the risk of parkinsonism in welders. Validity participants recruited from three similar shipyards were asked to give consent for access to personnel files and complete the questionnaire. Responses on the questionnaire were compared with information extracted from personnel records. Reliability participants were recruited from the same shipyards and were asked to complete the questionnaire at two different times approximately 4 weeks apart. Percent agreement, kappa, intraclass correlation coefficient (ICC), and sensitivity and specificity were used as measures of validity and/or reliability. Personnel files were obtained for 101 of 143 participants (70%) in the validity study, and 56 of the 95 (58.9%) participants in the reliability study completed the retest of the questionnaire. Validity scores for items extracted from personnel files were high. Percent agreement for employment dates and job titles ranged from 83-100%, while ICC for start and stop dates ranged from 0.93-0.99. Sensitivity and specificity for current job title ranged from 0.5-1.0. Reliability scores for demographic, medical and health behavior items were mainly moderate or high, but ranged from 0.19 to 1.0. Most recent job/title items such as title, types of welding performed, and material used showed substantial to perfect agreement. Certain determinants of exposure such as days and hours per week exposed to welding fumes demonstrated mainly moderate agreement (kappa= 0.42-0.47, percent agreement 63-77%); however, mean days and hours reported did not differ between test and retest. The results of this study suggest that participants' self-report for job title and dates employed are valid compared with employer records. While kappa scores were low for some medical conditions and for caffeine consumption, high kappa scores for job title, dates worked, types of welding, and materials welded suggest participants generated reproducible answers important for occupational exposure assessment.

Adam33 polymorphisms are associated with COPD and lung function in long-term tobacco smokers.

BACKGROUND: Variation in ADAM33 has been shown to be important in the development of asthma and altered lung function. This relationship however, has not been investigated in the population susceptible to COPD; long term tobacco smokers. We evaluated the association between polymorphisms in ADAM33 gene with COPD and lung function in long term tobacco smokers. METHODS: Caucasian subjects, at least 50 year old, who smoked >or= 20 pack-years (n = 880) were genotyped for 25 single nucleotide polymorphisms (SNPs) in ADAM33. COPD was defined as an FEV1/FVC ratio < 70% and percent-predicted (pp)FEV1 < 75% (n = 287). The control group had an FEV1/FVC ratio >or= 70% and ppFEV(1) >or= 80% (n = 311) despite >or= 20 pack years of smoking. Logistic and linear regressions were used for the analysis. Age, sex, and smoking status were considered as potential confounders. RESULTS: Five SNPs in ADAM33 were associated with COPD (Q-1, intronic: p < 0.003; S1, Ile --> Val: p < 0.003; S2, Gly --> Gly: p < 0.04; V-1 intronic: p < 0.002; V4, in 3' untranslated region: p < 0.007). Q-1, S1 and V-1 were also associated with ppFEV1, FEV1/FVC ratio and ppFEF25-75 (p values 0.001 - 0.02). S2 was associated with FEV1/FVC ratio (p < 0.05). The association between S1 and residual volume revealed a trend toward significance (p value < 0.07). Linkage disequilibrium and haplotype analyses suggested that S1 had the strongest degree of association with COPD and pulmonary function abnormalities. CONCLUSION: Five SNPs in ADAM33 were associated with COPD and lung function in long-term smokers. Functional studies will be needed to evaluate the biologic significance of these polymorphisms in the pathogenesis of COPD.

Examining the consulting physician model to enhance the school nurse role for children with asthma.

BACKGROUND: The Centers for Disease Control and Prevention's Strategies for Addressing Asthma Within a Coordinated School Health Program recommends a consulting physician for schools to help manage asthma. The literature examines the effects when a school nurse is present, but the addition of a consulting physician is not well understood. The purpose of this study is to assess the effect of having a consulting physician on school absenteeism and children sent home due to health reasons for children with asthma and all children pooled together. METHODS: A 2-year preimplementation group cohort and 1-year implementation group cohort of grades K-6 in an urban school district were used to determine the impact of a consulting physician on school absenteeism for children with asthma and all children pooled together. RESULTS: A consulting physician was significantly associated with reduced missed school days for children with asthma and all children as a group. All children pooled together were 44% more likely (OR = 1.44, 95% CI = 1.31-1.58) to be sent home without the consulting physician. There was a reduction from 13.8% to 12.6% of sent home events in children with asthma. CONCLUSIONS: Having consulting physicians in school districts appears to be associated with fewer days of school absence. The results provide additional evidence and suggest that more research is required to determine if this association is valid and to better understand the cause of such an association.

The relationship between school absence, academic performance, and asthma status.

BACKGROUND: Children with asthma experience more absenteeism from school compared with their nonasthma peers. Excessive absenteeism is related to lower student grades, psychological, social, and educational adjustment. Less is known about the relationship between the presence of asthma and the academic achievement in school-aged children. Since students with asthma miss more days from school, this may negatively impact their academic achievement. The goal of this study was to investigate the relationships between absenteeism, presence of asthma, and asthma severity level with standardized test level performance in a predominantly African American urban school district. METHODS: A cross-sectional analysis was conducted of 3812 students (aged 8-17 years) who took the Missouri Assessment Program (MAP) standardized test during the 2002-2003 academic year. RESULTS: After adjustment for covariates, a significant inverse relationship was found between absenteeism and test level performance on the MAP standardized test in all children (F = 203.9, p < .001). There was no overall difference in test level achievement between those with and without asthma (p = .12). Though not statistically different, those with persistent asthma showed a modestly increased likelihood of scoring below Nearing Proficient compared with those with mild intermittent asthma (adjusted odds ratio = 1.93, 95% confidence intervals = 0.93-4.01, p = .08). CONCLUSIONS: A negative impact of absenteeism on standardized test level achievement was demonstrated in children from an urban African American school district. Children with asthma perform the same academically as their nonasthma peers. However, those with persistent asthma show a trend of performing worse on MAP standardized test scores and have more absence days compared with other students. More research is warranted on the effects of persistent asthma on academic achievement.

IL13 promoter polymorphism 1112C/T modulates the adverse effect of tobacco smoking on lung function.

RATIONALE: Although the duration and amount of cigarette smoking correlate with reduction in pulmonary function, there is still variation among individual responses. IL-13 is involved in pulmonary inflammation, remodeling, and susceptibility to chronic obstructive pulmonary disease (COPD). OBJECTIVES: We investigated whether the relationships between smoking and the lung function measures FEV(1) and FEV(1)/FVC ratio are modulated by IL13 polymorphisms. METHODS: Smokers (>or=20 pack-years), aged at least 40 years old (n = 1,073), were genotyped for three single nucleotide polymorphisms (SNPs; -1112C/T [rs1800925], +2044G/A [rs20541, R130Q], and +2525G/A [rs1295685]) in the IL13 gene. Linear, quantile, and logistic regression methods were used to assess the effect of cigarette smoking (pack-years), IL13 polymorphisms, and their interaction on %predicted FEV(1) and FEV(1)/FVC ratio. Age, sex, and current smoking status were included as confounders. MEASUREMENTS AND MAIN RESULTS: The number of pack-years smoked was associated with a lower value for both %predicted FEV(1) and FEV(1)/FVC (P < 0.001). The three SNPs were not associated with lung function measures; however, there was a significant combined effect between smoking and the promoter polymorphism -1112C/T on %predicted FEV(1) (P for interaction < 0.03 for mean %predicted FEV(1) and < 0.0001 for 90th percentile %predicted FEV(1)). Every 20-pack-year increment in smoking was associated with a 2.4% reduction in mean %predicted FEV(1) in the common homozygous (CC) or heterozygous (CT) promoter genotypes, and an 8.2% reduction in mean %predicted FEV(1) in minor allele homozygotes (TT, recessive model). CONCLUSIONS: An IL13 polymorphism in the promoter region may modulate the adverse effects of cigarette smoking on pulmonary function in long-term cigarette smokers.