Systematic review of the QoR-15 score, a patient- reported outcome measure measuring quality of recovery after surgery and anaesthesia.

BACKGROUND: The QoR-15 is a patient-reported outcome questionnaire that measures the quality of recovery after surgery and anaesthesia. We aimed to perform a systematic review and meta-analysis of the measurement properties of the QoR-15. METHODS: Studies reporting measurement properties or interpretability of the QoR-15 after surgery were eligible for inclusion. All languages were included in the PubMed and Embase search. The COSMIN guidelines for systematic reviews of patient-reported outcome measurements were followed. Criteria for good measurement properties outlined in the consensus-based guidelines for selecting outcome measurement instruments for clinical trials were applied. A metaanalysis and synthesis of data across studies was performed. RESULTS: Nine hundred and thirty-three titles were identified, and six articles were included in the study. The study population comprised 1548 patients undergoing a variety of surgical elective procedures. The QoR-15 was validated in English, Danish, Chinese, and Portuguese. High-quality evidence for good content validity, good internal consistency (Cronbach's α of 0.836), and essential unidimensionality of the QoR-15 as a measurement of postoperative quality of recovery was found. There was at least moderate-quality evidence of good reliability of the QoR-15 (intraclass correlation of 0.989) and good error of measurement (standard error of measurement of 1.85). The upper 95% confidence limit of the smallest detectable change was 3.63, and the minimal clinical important difference was 8.0. CONCLUSIONS: The QoR-15 fulfils requirements for outcome measurement instruments in clinical trials and is the first measurement instrument of postoperative quality of recovery to undergo a systematic review according to the COSMIN checklist.

Incidence of venous thromboembolic events in enhanced recovery after surgery for colon cancer: a retrospective, population-based cohort study.

AIM: Both the Danish and the National Institute of Clinical Excellence (NICE) guidelines recommend prolonged thromboprophylaxis (PT) with low-molecular-weight heparin (LMWH) for 28 days postoperatively after elective surgery for colon cancer. The evidence relies on data from two randomized clinical trials (RCTs) that included not only colon cancers but also other abdominal cancers or benign colorectal diseases. Neither of those studies investigated the risk of venous thromboembolism (VTE) under enhanced recovery after surgery (ERAS). We aim to describe the risk of VTE and estimate the cost of preventing one case of VTE by PT under ERAS. METHOD: This was a retrospective study of 2230 patients undergoing elective surgery for colon cancer Stage I-III in the Capital Region of Denmark, 1 June 2008 to 31 December 2013. Patients who were discharged on postoperative day 28 or later, died during admission or were discharged with a vitamin K antagonist, novel oral anticoagulants or LMWH were excluded. Patients with rectal cancer only were not included. End-points were symptomatic VTE diagnosed within 60 days postoperatively. RESULTS: Three-hundred and thirty patients were excluded. For the remaining 1893, the median length of stay (LOS) was 4 [interquartile range (IQR): 3-5] days. Of these 1893 patients, four (0.20%) experienced a nonfatal symptomatic VTE. All four patients had other postoperative complications before the VTE. The cost of each symptomatic VTE prevented is estimated to be between £63 709 and £111 455 when medication and home-care nursing are included. CONCLUSION: The risk of symptomatic VTE after uncomplicated, elective surgery for colon cancer with ERAS seems negligible and the cost-effectiveness of PT to prevent one symptomatic VTE seems questionable.

Domestic dog exposure at birth reduces the incidence of atopic dermatitis.

BACKGROUND: While the etiopathogenesis of atopic dermatitis is complex and poorly understood, neonatal exposures are important for disease occurrence. However, the effect of dog exposure on the risk of atopic dermatitis is unresolved. OBJECTIVE: We investigated whether domestic dog exposure affected the risk of atopic dermatitis in children during the first 3 years of life. METHODS: Copenhagen Prospective Studies on Asthma in Childhood (COPSAC) are ongoing prospective clinical birth cohort studies. Data from 411 children born to mothers with asthma (COPSAC2000 ) and 700 unselected children (COPSAC2010 ) were analyzed following the same protocols at the same research site. Atopic dermatitis was diagnosed prospectively according to the Hanifin-Rajka criteria. Parental history of asthma, eczema, or rhinitis was defined by self-reported physician diagnosis. In the COPSAC2000 , maternal specific serum IgE against eight inhalant allergens was sampled after the children's birth and at pregnancy week 24 in the COPSAC2010 cohort. Associations between dog exposure and atopic dermatitis were analyzed by Cox proportional hazard regression models and adjusted for lifestyle confounders. RESULTS: In the COPSAC2000 and COPSAC2010 cohorts, the risk of atopic dermatitis was significantly lower in children with domestic dog exposure (adjusted HR = 0.46 [0.25-0.87], P = 0.02; and adjusted HR = 0.58 [0.36-0.93], P = 0.03, respectively). The risk of atopic dermatitis decreased in a dose-dependent manner with increasing number of dogs (adjusted HR = 0.58 [0.38-0.89], P = 0.01) in the COPSAC2010 . The protective effect was restricted to children born to mothers with atopic disease in the unselected COPSAC2010 cohort (adjusted HR = 0.39 [0.19-0.82], P = 0.01), as no effect was observed in children born to mothers without atopic disease (adjusted HR = 0.92 [0.49-1.73], P = 0.79). Paternal atopic status did not affect the risk of atopic dermatitis. We found no significant interaction between the CD14 T/T genotype and domestic dog exposure in either cohort (COPSAC2000 , P = 0.36; and COPSAC2010 cohort, P = 0.42). CONCLUSION: Neonatal domestic dog exposure was associated with a strongly reduced risk of atopic dermatitis in two independent birth cohorts and in a dose-dependent manner. While the mechanisms involved are unclear, our findings raise the question of whether in utero exposures may affect the risk of atopic dermatitis and emphasize the importance of the early environment for disease trajectory.

High breast milk IL-1ß level is associated with reduced risk of childhood eczema.

BACKGROUND: We recently demonstrated a dual effect of breastfeeding with increased risk of eczema and decreased risk of wheezing in early childhood by increasing breastfeeding length. We hypothesize that immune mediators in breast milk could explain such association either through a direct effect or as a surrogate marker of maternal immune constitution. OBJECTIVE: To investigate the possible association between cytokine and chemokine levels in breast milk and development of eczema and recurrent wheeze during early childhood. METHODS: Levels of 19 pro-inflammatory and immunoregulatory cytokines and chemokines were measured in 223 breast milk samples from mothers in the Copenhagen Prospective Study on Asthma in Childhood2000 (COPSAC) high-risk birth cohort. Eczema and recurrent wheeze at the age of 0-3 years were prospectively diagnosed by COPSAC physicians adherent to predefined validated algorithms. Association analyses were performed by Cox regression adjusting for potential confounding factors and by multivariable principal component analysis. RESULTS: Increased IL-1ß in breast milk (≥ 0.7 pg/mL) was associated with more than a halved risk of eczema before age three (aHR = 0.41; 95% CI = 0.24-0.68; P < 0.001), which remained significant after false discovery rate adjustment (P = 0.008). The principal component analysis confirmed that a mediator pattern dominated by high levels of IL-1ß, IL-17A, and CCL17 and low levels of CXCL1 and TSLP in breast milk protected against eczema (aHR = 0.82; 95% CI = 0.68-0.98; P = 0.03). No associations were observed for recurrent wheeze. CONCLUSIONS AND CLINICAL RELEVANCE: Elevated breast milk IL-1ß level was associated with decreased risk of early childhood eczema suggesting either a direct protective effect of IL-1ß or IL-1b acting as a proxy for a healthy maternal immune system protecting high-risk offspring from eczema.

Differentiation of Metastatic and Non-Metastatic Mesenteric Lymph Nodes by Strain Elastography in Surgical Specimens.

PURPOSE: To investigate if strain elastography could differentiate between metastatic and non-metastatic mesenteric lymph nodes ex-vivo. MATERIALS AND METHODS: 90 mesenteric lymph nodes were examined shortly after resection from 25 patients including 17 patients with colorectal cancer and 8 patients with Crohn's disease. Ultrasound-based strain elastography was performed with a linear probe. Tissue hardness in lymph nodes was assessed using visual scales and measuring the strain ratio. B-mode characteristics were also recorded. Pathological diagnosis with grading of fibrosis served as the reference standard. RESULTS: 20 lymph nodes were metastatic and 70 lymph nodes were non-metastatic. The strain ratios of metastatic and non-metastatic lymph nodes were significantly different (1.83 vs. 1.42, p = 0.021). The VAS scale (0 - 100) for tissue hardness gave higher mean values for metastatic than non-metastatic nodes, but the difference was not significant (65.5 vs. 55.0, p = 0.055). There was no difference between lymph nodes in Crohn's and non-metastatic cancer specimens. The metastatic lymph nodes were significantly more fibrotic than the non-metastatic lymph nodes by the ordinal fibrosis score (0 - 3). In an ROC analysis, quantitative strain imaging was not superior to the measurement of the short-axis diameter of lymph nodes in differentiating metastatic from non-metastatic mesenteric lymph nodes ex-vivo. CONCLUSION: Strain elastography is correlated to fibrosis in lymph nodes and a significant difference was observed on a group level using the strain ratio. Due to measurement overlap, individual mesenteric lymph nodes could not be identified accurately as metastatic or not in this ex-vivo model by strain imaging alone.

Strain Elastography Evaluation of Rectal Tumors: Inter- and Intraobserver Reproducibility.

PURPOSE: Elastography is a promising method for the identification and differentiation of malignant tissue in several organ systems. The primary aim was to evaluate the inter- and intraobserver reproducibility of endorectal strain elastography differentiation of adenomas and adenocarcinomas. The secondary aim was to compare the performance of strain elastography to endorectal ultrasonography (ERUS) examinations. MATERIALS AND METHODS: Consecutive inclusion of 95 ERUS examinations and 110 elastography video loops with ERUS overlay mode. Video loops were randomized and evaluated by eight observers on two separate occasions. Observers were blinded to all clinical information except the circumferential location of the tumor. A continuous visual analog scale (VAS) and a categorical scale (W-score) were used for elastography evaluation. ERUS loops were T-staged according to the TNM classification system. Histopathological evaluation of surgical resection specimen was used as the reference standard. RESULTS: Strain elastography visual evaluation yielded intraobserver variability from 0.86 to 0.97 and interobserver variability of 0.99. VAS strain elastography differentiation of adenomas (pT0) and adenocarcinomas (pT1 - 4) yielded sensitivity, specificity, accuracy, positive and negative predictive values of 0.94, 0.71, 0.89, 0.92 and 0.78, respectively. The corresponding ERUS values were 0.83, 0.64, 0.79, 0.88 and 0.54, respectively. CONCLUSION: Visual evaluation of elastography loops is highly reproducible in an offline setting with blinded observers, and correlates significantly with pT-stages. Strain elastography performs better than ERUS and might consequently improve staging.

Endorectal ultrasonography, strain elastography and MRI differentiation of rectal adenomas and adenocarcinomas.

AIM: Strain elastography is a method for recording tissue hardness. Strain in different areas may be compared using strain ratio (SR). The aims of this study were to validate a previously proposed SR cut-off value of 1.25 for differentiating adenocarcinomas from adenomas and to compare the performance of endorectal ultrasonography (ERUS), strain elastography and MRI in the same patients. METHOD: A prospective evaluation of 120 consecutive patients with rectal neoplasia, using a predetermined elastography strain ratio cut-off value, was performed to differentiate adenomas from adenocarcinomas. ERUS and MRI were performed according to standard routine at Haukeland University Hospital, defining T0 as adenomas and T1-T4 as adenocarcinomas. Subsequent histopathology was used as the reference standard. RESULTS: Histopathological evaluation revealed 21 adenomas and 99 adenocarcinomas. Sensitivity, specificity and accuracy (with 95% CI) were as follows: ERUS: 0.96 (0.90-0.99), 0.62 (0.40-0.80) and 0.90 (0.83-0.94); elastography SR: 0.96 (0.90-0.99), 0.86 (0.66-0.96) and 0.94 (0.88-0.97); and MRI: 0.99 (0.94-1.00), 0.07 (0.00-0.31) and 0.87 (0.80-0.93). CONCLUSION: This study confirms that the elastography SR assessment accurately differentiates sessile adenomas from adenocarcinomas. SR assessment has a superior ability to differentiate adenomas and adenocarcinomas when compared with ERUS and MRI. MRI examination seems unable to recognize adenomas and should be interpreted with care when early-stage rectal neoplasia is suspected.

Combined endorectal ultrasonography and strain elastography for the staging of early rectal cancer.

AIM: Strain elastography is a novel approach to rectal tumour evaluation. The primary aim of this study was to correlate elastography to pT stages of rectal tumours and to assess the ability of the method to differentiate rectal adenomas (pT0) from early rectal cancer (pT1-2). Secondary aims were to compare elastography with endorectal ultrasonography (ERUS) and to propose a combined strain elastography and ERUS staging algorithm. METHOD: In all, 120 consecutive patients with a suspected rectal tumour were examined in this staging study. Patients receiving surgery without neoadjuvant radiotherapy were included (n = 59). All patients were examined with ERUS and elastography. Treatment decisions were made by multidisciplinary team (MDT) assessment, without considering the strain elastography examination. RESULTS: Histopathology identified 21 adenomas, 13 pT1, 9 pT2, 15 pT3 and one pT4. Mean elastography strain ratios were predictive of T stage (P = 0.01). Differentiation of adenomas from early rectal cancer (pT1-2) had sensitivity, specificity and accuracy of 0.82, 0.86 and 0.84 for elastography and 0.82, 0.62 and 0.72 for ERUS. A combined staging algorithm was developed to identify tumours eligible for local resection. Based on MDT evaluation 32% of tumours later identified as pT0 or pT1 were treated with total mesorectal excision, even though a local excision might have sufficed. Combined ERUS and elastography evaluation would have significantly reduced this number to 9% (P = 0.008). CONCLUSION: Elastography may improve the staging of adenomas and early rectal cancer compared with ERUS alone. Combined ERUS and elastography assessment is likely to further improve the selection of patients for local resection.

TGIF1 is a negative regulator of MLL-rearranged acute myeloid leukemia.

Members of the TALE (three-amino-acid loop extension) family of atypical homeodomain-containing transcription factors are important downstream effectors of oncogenic fusion proteins involving the mixed lineage leukemia (MLL) gene. A well-characterized member of this protein family is MEIS1, which orchestrates a transcriptional program required for the maintenance of MLL-rearranged acute myeloid leukemia (AML). TGIF1/TGIF2 are relatively uncharacterized TALE transcription factors, which, in contrast to the remaining family, have been shown to act as transcriptional repressors. Given the general importance of this family in malignant hematopoiesis, we therefore tested the potential function of TGIF1 in the maintenance of MLL-rearranged AML. Gene expression analysis of MLL-rearranged patient blasts demonstrated reduced TGIF1 levels, and, in accordance, we find that forced expression of TGIF1 in MLL-AF9-transformed cells promoted differentiation and cell cycle exit in vitro, and delayed leukemic onset in vivo. Mechanistically, we show that TGIF1 interferes with a MEIS1-dependent transcriptional program by associating with MEIS1-bound regions in a competitive manner and that the MEIS1:TGIF1 ratio influence the clinical outcome. Collectively, these findings demonstrate that TALE family members can act both positively and negatively on transcriptional programs responsible for leukemic maintenance and provide novel insights into the regulatory gene expression circuitries in MLL-rearranged AML.

Strain assessment in surgically resected inflammatory and neoplastic bowel lesions.

PURPOSE: To investigate whether ultrasound-based strain imaging can discriminate between colorectal adenocarcinomas and stenotic Crohn's lesions in newly resected surgical specimens. MATERIALS AND METHODS: Resected surgical specimens from 27 patients electively operated for colorectal tumors or stenotic lesions from Crohn's disease were prospectively examined with ultrasonography using a Hitachi HV 900 US scanner with real-time elastography (RTE). Three different methods were applied to assess tissue strain: A four-level categorical visual classification, a continuous visual analog scale (VAS, 0 - 100) and a strain ratio (SR) measurement between the lesion and surrounding reference tissue. The imaged sections were marked and subsequently examined by a pathologist. Results from RTE were evaluated according to diagnosis, degree of fibrosis, inflammatory parameters, tumor stage and grade. RESULTS: 16 sections from Crohn's lesions, 18 sections from adenocarcinomas and 4 sections from adenomas were examined. Both adenocarcinomas and Crohn's lesions were found to be harder than the surrounding tissue, but they could not be discriminated from each other by any of the strain imaging evaluation methods. All adenocarcinomas had significantly higher strain ratios than adenomas. The categorical classification differentiated poorly between Crohn's lesions, adenocarcinomas and adenomas. Categorical evaluation and VAS score showed fair interobserver agreement. SR measurements provided semi-quantitative strain data and added improved information about elasticity properties, despite substantial intra-observer variation. CONCLUSION: Sonoelastography with SR measurements and visual evaluation of strain differences could not differentiate stenotic Crohn's lesions from adenocarcinomas in resected bowel specimens. A small number of adenomas were found to be significantly softer than adenocarcinomas using the same evaluation methods. The tumor stage or grade did not have a significant impact on the elastography results.

Real-Time Elastography: Strain Ratio Measurements Are Influenced by the Position of the Reference Area.

PURPOSE: Real-time elastography (RTE) is an ultrasound-based method for the visualization of relative strain distribution in soft tissues. Strain ratio is a semi-quantitative measurement of strain differences between two user-defined areas in an elastogram. The aim of this study was to evaluate the impact of the size and location of a reference area when measuring the strain ratio of focal lesions in a tissue-mimicking phantom and in normal liver tissue. We also investigated whether the strain ratio was affected by changing the scanner parameter: elasticity dynamic range (E-dyn). MATERIALS AND METHODS: Two investigators individually collected data by scanning 4 spherical inclusions with different elasticity in a phantom in which the elastic modulus was known in both the lesions and the background. Subsequently, a liver scan was performed in-vivo using the same scanning protocol. Five different setups with changes in reference area position or size were tested. All eight levels of the scanner setting Edyn were recorded for each setup and the strain ratio was measured in 3 different representative elastograms for each recording situation. RESULTS: The four inclusions had significantly different mean strain ratio levels (p < 0.01) when compared to the surrounding material. Changing the position of the reference area to a deeper position influenced the strain ratio measurements significantly for all phantom lesions and in the liver. Changing the size of the reference area, while keeping the center depth unchanged, did not influence the mean strain ratio levels significantly. The strain ratio was independent of the E-dyn parameter setting. The intraand interobserver reliability was high when measuring the strain ratio with a free-hand technique. CONCLUSION: Strain ratio provides reproducible measurements of inclusions representing different elastic contrasts using a free-hand technique in vitro. Changes in the distance of the reference areas to the ultrasound probe, representing the stress source, seem to have a significant impact on strain ratio measurements.

Endorectal elastography in the evaluation of rectal tumours.

AIM: Real-time elastography visualizes tissue compliance using an ultrasound platform. Elastography has been used, particularly in the breast, to characterize indeterminate lesions on B-mode imaging as either benign or malignant. The primary aim of this study was to assess the feasibility of routine endorectal elastography to evaluate rectal neoplasia. The secondary aim was to correlate elastography data with histopathological end-points. METHOD: Sixty-nine patients referred to the outpatient clinic of the Department of Colorectal Surgery at Haukeland University Hospital for the evaluation of rectal tumours were included in this prospective cohort study. All patients underwent digital rectal examination, rigid rectoscopy with biopsy, endorectal ultrasonography and endorectal elastography. In each case a strain ratio was calculated, comparing the tumour tissue with adjacent reference tissue that appeared normal on ultrasound scanning. RESULTS: Histopathologically there were 23 adenomas and 45 adenocarcinomas. One patient died before surgical treatment. Adequate elastography images were obtained in 66/69 (96%) patients. Optimal discrimination of malignant and benign lesions was obtained using a strain ratio cut-off value of 1.25 (sensitivity, 0.93; specificity, 0.96; and accuracy, 0.94). CONCLUSION: Endorectal elastography can be performed as an integral part of the clinical evaluation of rectal tumours and has good patient compliance. The method is a promising modality for the discrimination between adenocarcinoma and adenoma of the rectum.

Agricultural biosecurity.

The prevention and control of new pest and disease introductions is an agricultural challenge which is attracting growing public interest. This interest is in part driven by an impression that the threat is increasing, but there has been little analysis of the changing rates of biosecurity threat, and existing evidence is equivocal. Traditional biosecurity systems for animals and plants differ substantially but are beginning to converge. Bio-economic modelling of risk will be a valuable tool in guiding the allocation of limited resources for biosecurity. The future of prevention and management systems will be strongly influenced by new technology and the growing role of the private sector. Overall, today's biosecurity systems are challenged by changing national priorities regarding trade, by new concerns about environmental effects of biological invasions and by the question 'who pays?'. Tomorrow's systems may need to be quite different to be effective. We suggest three changes: an integration of plant and animal biosecurity around a common, proactive, risk-based approach; a greater focus on international cooperation to deal with threats at source; and a commitment to refocus biosecurity on building resilience to invasion into agroecosystems rather than building walls around them.

Prevalence of antibodies to Yersinia enterocolitica O:3 among Norwegian military recruits: association with risk factors and clinical manifestations.

IgG antibody activity to Yersinia enterocolitica serogroup O:3 was detected in sera from 56 (7.4%) of 755 Norwegian military recruits, using an enzyme-linked immunosorbent assay. The highest prevalence was found among recruits from Oslo city (12/56, 21.4%). The recruits answered a questionnaire which covered demographic data, specific exposures, and clinical information. The following risk factors were found to be independently associated with IgG activity in logistic regression analysis: receiving drinking water from a private well (odds ratio (OR) = 3.40; p = 0.004), being a resident of Oslo city (OR = 2.99; p = 0.006), and living in eastern Norway (OR = 2.25; p = 0.015). By univariate analysis, living in an urban area was associated with IgG activity, but this factor did not independently affect risk. Present or previous contact with animals, including pigs, and travels abroad were not associated with an increased risk. Yersinia enterocolitica O:3 seropositive recruits were more likely to report previous surgery for suspected appendicitis than seronegative individuals (OR = 4.26; p = 0.0024). Among recruits with previous appendectomy, mesenteric lymphadenitis as the sole peroperative finding was more common in patients with IgG activity to Y. enterocolitica O:3 (4/7) than in seronegative patients (1/19) (p = 0.01). Recurrent diarrhea, steatorrhea or joint complaints were not associated with antibody activity.

Acute effects and exposure to organic compounds in road maintenance workers exposed to asphalt.

Subjective symptoms and exposure to organic compounds were recorded in road repair and construction workers. Abnormal fatigue, reduced appetite, laryngeal/pharyngeal irritation, and eye irritation were recorded more often in such workers handling asphalt than in a corresponding reference group without asphalt exposure. Mean daily exposure to volatile compounds was only occasionally above 1 ppm. Mean exposure to asphalt fume was 0.358 mg/m3. There was no correlation between symptoms and total amount of volatile compounds, but a significant positive correlation was demonstrated between symptoms and some substances. The highest correlation was found for 1, 2, 4 trimethyl benzene. Symptoms increased with increasing asphalt temperature and with increasing concentrations of asphalt fumes. Amine addition did not increase the sum of symptoms, but soft asphalt seems to result in fewer symptoms than the harder types. Symptoms were not related to external factors like weather, traffic density, or specific working operations. As preventive measures, asphalt temperature should be kept below 150 degrees C, fume concentrations below 0.40 mg/m3, and if possible, the use of harder asphalt types which also require high temperatures should be avoided.

Feeding strategies of the horseflies Hybomitra expollicata and Tabanus bromius in southern France.

Blood-feeding success of female horseflies, Hybomitra expollicata Pandellé and Tabanus bromius L. (Diptera: Tabanidae), was studied. Bloodmeal weights of flies permitted different periods of residence on a horse's belly were estimated, and related to subsequent ovarian development and the number of mature eggs produced. Fitness gain per visit to a host (as estimated by the number of mature eggs produced) increased more rapidly with residence time on the host for H.expollicata than for T.bromius. H.expollicata inhibed blood more rapidly and, above a threshold bloodmeal size, produced a consistently higher number of eggs per unit weight of blood ingested. The feeding strategies of the two species are compared.

Respiratory dysfunction after potroom asthma.

Thirty-five men developed bronchial asthma while working in the potrooms in a primary aluminum production plant. Their asthma was diagnosed as work-related ("potroom asthma"). When examined 1-43 months after cessation of exposure (average follow-up period 2.5 yr), the group had an increased relative risk of morning cough (RR 1.7 CL95% 0.6-5.1), dyspnea on exertion (RR 2.8 CL95% 0.9-8.4), and wheezing (RR 6.1 CL95% 2.3-16.3) compared to controls from the same plant, in a 1:2 matched analysis. Matching criteria were age, smoking habits, and time of employment in the plant. The group means for FEV1 and MMEF were lower than for the controls, but the differences were not statistically significant. Ten of the 35 reported persisting asthma, dyspnea at night, or dyspnea on exertion. The study indicates an increased risk of respiratory dysfunction after potroom asthma. Medical follow-up after cessation of exposure is recommended.