A multi-centre randomized controlled trial of open vs closed management of the rectal defect after transanal endoscopic microsurgery.

AIM: Transanal endoscopic microsurgery (TEM) is a technically challenging strategy that allows expanded indications for local excision of rectal lesions. Transluminal suturing is difficult, so open management of the resultant defect is appealing. Expert opinion suggests there is more pain when the defect is left open. The aim of this study was to determine if closure of the defect created during full thickness excision of rectal lesions with TEM leads to less postoperative pain compared to leaving the defect open. METHOD: At the time of surgery, patients undergoing a full thickness TEM were randomized to sutured (TEM-S) or open (TEM-O) management of the rectal defect. At five Canadian academic colorectal surgery centres, experienced TEM surgeons enrolled patients ≥ 18 years treated by full thickness TEM. The primary outcome was postoperative pain measured by the visual analogue scale. Secondary outcomes included postoperative pain medication use and 30-day postoperative complications, including bleeding, infection and hospital readmission. RESULTS: Between March 2012 and October 2013, 50 patients were enrolled and randomized to sutured (TEM-S, n = 28) or open (TEM-O, n = 22) management of the rectal defect. There was no difference between the two study groups in postoperative pain on postoperative day 1 (2.8 vs 2.6, P = 0.76), day 3 (2.8 vs 2.1, P = 0.23) and day 7 (2.8 vs 1.7, P = 0.10). CONCLUSION: In this multicentre randomized controlled trial, there was no difference in postoperative pain between sutured or open defect management in patients having a full thickness excision with TEM.

Coloseminal vesicle fistula after low anterior resection: Report of a case and review of the literature.

INTRODUCTION: A rectoseminal vesicle fistula after a low anterior resection for rectal cancer is a rare complication despite their anatomic proximity. From a Medline search from 1966 to date, a total of twenty-one previous cases of coloseminal vesicle fistula have been reported. From these cases, eleven were a complication of laparoscopic low anterior resection for rectal cancer. DESCRIPTION OF THE CASE: This report presents the case of a 63-year-old patient who was readmitted to the hospital on the fifteenth postoperative day after his surgical intervention for fever, abdominal pain, dysuria and pneumaturia. A sinography with water-soluble contrast revealed a tract between the rectum and the seminal vesicle. The condition was treated conservatively with antibiotics, urinary catheter and a transanastomotic Malecot probe for abscess drainage. The fistula had completely recovered on postoperative day 71 and the patient is still symptoms free, six months after the complication developed. DISCUSSION: This case reinforces the presumed link between anastomotic leakage and rectoseminal vesicle fistula in cases of low anterior resection while reviewing and summarizing similar previously reported cases on the course of the disease, diagnostic procedures and treatment options. CONCLUSION: Seminal vesicle are susceptible to fistula in oncological resection of rectum. Both CT scan with water-soluble contrast or sinography are effective diagnostic examinations. Depending on the characteristics of the fistula, conservative approach may be adequate and benefits much less morbidities than the surgical options.

Subacromial temperature profile during bipolar radiofrequency use in shoulder arthroscopy. Comparison of Coblation® vs. VAPR®.

BACKGROUND: The use of bipolar electrodes for arthroscopic procedures carries a theoretical ex vivo risk of inducing burn injuries. Few studies have measured the in vivo temperatures produced by bipolar electrodes during arthroscopy, and their results are conflicting. The objective of this study was to evaluate the temperature profile within the subacromial space during shoulder arthroscopy with two different electrode systems. HYPOTHESIS: The primary hypothesis was that the two electrode systems produced similar temperature variations and peak temperatures. The secondary hypothesis was that neither electrode system produced irrigation-fluid temperatures above the tissue-damage threshold. MATERIAL AND METHODS: A comparative, prospective, single-centre, single-surgeon, single-blind study was conducted to compare the Coblation® system (Smith&Nephew, Andover, MA, USA) and the VAPR® system (DePuy Synthes Mitek Sports Medicine, Raynham, MA, USA) in 13 patients undergoing shoulder arthroscopy. A temperature probe inserted into the subacromial space was used to record temperatures at 10-second intervals for 60seconds during continuous radiofrequency application. RESULTS: Mean baseline temperature was 21.4±0.7°C with VAPR® and 23.0±2.2°C with Coblation®. No significant between-group differences were found during the first 40seconds. The mean peak temperature reached after 60seconds was 25.0±1.9°C with VAPR® and 27.9±2.8°C with Coblation® (P<0.05). DISCUSSION: Few studies have compared the in vivo temperatures produced during arthroscopy by different electrode systems. In vivo studies have established that temperature increases can cause tissue damage, particularly to chondrocytes, and that the irrigation flow rate plays a key role in lowering the in vivo temperatures. Our study showed a significant difference between the two electrode systems after 50seconds of use, with lower temperatures with the VAPR®. Nevertheless, neither system increased the irrigation-fluid temperatures above the tissue-damage threshold. Both systems can be used safely, provided the manufacturer instructions are followed and the irrigation system is effective. LEVEL OF EVIDENCE: II (prospective randomized trial).

Unmeasured costs of haemophilia: the economic burden on families with children with haemophilia.

INTRODUCTION AND OBJECTIVES: Although economic evaluations of haemophilia-related care have highlighted both the health care payer and societal perspectives, the costs to families with children with haemophilia have not been examined. This study determined the costs incurred by families of children with haemophilia, attending a haemophilia treatment centre (HTC), servicing a large geographical area in Eastern Canada. METHODS: Families recorded all direct and indirect costs associated with haemophilia-related care for a year. Costs incurred to receive care at the HTC and local health care centres were compared. The relationship between distance to the HTC and costs was modelled using linear regression. RESULTS: Participants included 31/45 children (68%) from 27 families attending the HTC. Median age was 12 years (range: 0.5-17 years); 24/31 (77%) had severe haemophilia. The median distance to the HTC and local health care facility was 230 km (range: 7-600 km) and 33.5 km (range: 2-400 km) respectively. Due to this difference in distance, 23/31 (74%) children do not attend the HTC for management of acute haemorrhage. The median annual total cost per family to attend the HTC is $775.93 (range: $200.00-$5741.00). The total cost to attend the HTC increases by $2.16 (95% CI 1.24-3.9) per kilometer from the HTC. The median total annual cost of haemophilia-related care per family is $1222.50 (range: $396.00-$8037.00). CONCLUSION: Families incur high costs related to haemophilia care. The distance to the HTC is a barrier to care. Improving access to HTCs is paramount in improving haemophilia-related outcomes.

Failed subacromial decompression. Risk factors.

BACKGROUND: Arthroscopic subacromial decompression (acromioplasty) is widely held to be effective, although pain may persist after the procedure. The objective of this study was to evaluate the proportion of patients with residual pain (i.e., the failure rate) after isolated subacromial decompression and to look for predictors of failure. MATERIAL AND METHOD: We conducted a retrospective multicentre study of 108 patients managed with isolated arthroscopic subacromial decompression between 2007 and 2011, for any reason. We excluded patients in whom surgical procedures on the rotator cuff tendons were performed concomitantly. Data were collected from the medical records, a telephone questionnaire, and radiographs obtained before surgery and at last follow-up. Failure was defined as persistent pain (visual analogue scale score>3) more than 6 months after surgery and at last follow-up. RESULTS: The failure rate was 29% (31/108). Two factors significantly predicted failure, namely, receiving workers' compensation benefits for the shoulder condition and co-planing. Heterogeneous calcific tendinopathy and deep partial-thickness rotator cuff tears were also associated with poorer outcomes, but the effect was not statistically significant. DISCUSSION: Co-planing may predict failure of subacromial decompression, although whether this effect is due to an insufficient degree of co-planing or to the technique itself is unclear. Nevertheless, in patients with symptoms from the acromio-clavicular joint, acromio-clavicular resection is probably the best option. Receiving workers' compensation benefits was also associated with treatment failure, as a result of well-known parameters related to the social welfare system. CONCLUSION: Isolated arthroscopic subacromial decompression is effective in 70% of cases. We recommend the utmost caution if co-planing is considered and/or the patient receives workers' compensation benefits for the shoulder condition, as these two factors are associated with a significant increase in the failure rate. LEVEL OF EVIDENCE: IV (retrospective study).

The clinical results of the Turnbull-Cutait delayed coloanal anastomosis: a systematic review.

Turnbull and Cutait described abdominoperineal pull-through followed by delayed coloanal anastomosis (DCA) in 1961. DCA could reduce anastomotic leaks, pelvic morbidity and use of stomas. Strong evidence about its clinical benefits is still lacking. This systematic review examined the clinical outcomes of DCA for the treatment of malignant or benign colorectal conditions. A systematic search of electronic medical databases was conducted. Two independent reviewers selected studies, extracted data and assessed risk of bias. The primary outcome was pelvic morbidity (anastomotic leak, pelvic abscess or sepsis, use of stoma). Fecal continence and survival data were also analyzed. From 1,251 citations, we included seven observational studies including 1,124 patients. All included studies were considered at high risk of bias. Two studies comparing DCA with immediate anastomosis reported a significant decrease in anastomotic leak, and pelvic abscess or sepsis. Low rates of pelvic morbidity were reported in the other five studies: anastomotic leak 0-7 %, pelvic abscess 0-11.8 % and pelvic sepsis 6.8-10 %. Rates of permanent stoma after DCA were low in six studies (1-6 %), with one study reporting an incidence of 25 %. Fecal continence was reported as satisfying in all studies. No differences were observed in a comparative setting. Survival data were reported in four studies. Clinical heterogeneity and methodological issues precluded meta-analysis. Based on retrospective evidence, DCA offers a low rate of anastomotic leak, pelvic morbidity and use of stoma, with reasonable fecal continence. Results are encouraging, but prospective studies are needed for comparison with standard of care.

Generation of human TRIM5alpha mutants with high HIV-1 restriction activity.

Rhesus macaque tripartite motif (TRIM)5alpha potently inhibits early stages of human immunodeficiency virus (HIV)-1 replication, while the human orthologue has little effect on this virus. We used PCR-based random mutagenesis to construct a large library of human TRIM5alpha variants containing mutations in the PRYSPRY domain. We then applied a functional screen to isolate human cells made resistant to HIV-1 infection by the expression of a mutated TRIM5alpha. This protocol led to the characterization of a human TRIM5alpha variant containing a mutation at arginine 335 as conferring resistance to HIV-1 infection. The level of protection stemming from expression of this mutant was comparable to that of previously described mutations at position 332. R332/R335 double mutants decreased permissiveness to HIV-1 and to other lentiviruses by 20- to 50-fold in TE671 fibroblasts and in the T-cell line SUP-T1, and prevented HIV-1 spreading infection as efficiently as the rhesus macaque TRIM5alpha orthologue did. The finding that only two substitutions in human TRIM5alpha can confer resistance to HIV-1 at levels as high as one of the most potent natural orthologues of TRIM5alpha removes a roadblock toward the use of this restriction factor in human gene therapy applications.

Using restrictive messages to limit high-fat foods or nonrestrictive messages to increase fruit and vegetable intake: what works better for postmenopausal women?

BACKGROUND/OBJECTIVES: To compare the effects of two dietary approaches on changes in dietary intakes and body weight: (1) an approach emphasizing nonrestrictive messages directed toward the inclusion of fruits and vegetables (HIFV) and (2) another approach using restrictive messages to limit high-fat foods (LOFAT). SUBJECTS/METHODS: A total of 68 overweight-obese postmenopausal women were randomly assigned to one of the two dietary approaches. The 6-month dietary intervention included three group sessions and ten individual sessions with a dietitian. Dietary food intake and anthropometric variables were measured at baseline, at 3 months and at 6 months. RESULTS: Energy density decreased in both groups after the intervention compared with baseline (HIFV, -0.3+/-0.2 kcal/g; LOFAT, -0.3+/-0.3 kcal/g; P<0.0001). Although body weight decreased significantly in both groups after the intervention compared with baseline (HIFV, -1.6+/-2.9 kg; LOFAT, -3.5+/-2.9 kg; P<0.0001), women in the LOFAT group lost significantly more body weight than women in the HIFV group (P=0.01). In the HIFV group, the decrease in energy density was found to be an independent predictor of body weight loss. CONCLUSIONS: The LOFAT approach induces more weight loss than does the HIFV approach in our sample of overweight-obese postmenopausal women.

Architectural strategies of Cornus sericea, a native but invasive shrub of Southern Quebec, Canada, under an open or a closed canopy.

BACKGROUND AND AIMS: Qualitative and quantitative studies of the pattern of invasive plant development is considered a key aspect in understanding invasiveness. An architectural analysis was therefore performed in order to understand the relationship between shoot architecture and invasiveness in red-osier dogwood, Cornus sericea (Cornaceae). METHODS: The structural and ontogenic characteristics of individuals in invading and non-invading populations in the native range of the species were compared to test the implication of developmental plasticity on invasiveness. KEY RESULTS AND CONCLUSIONS: The results show that the shrub has a modular architecture governed by strong developmental rules. Cornus sericea is made up of two levels of organization, each with its own intrinsic sequence of differentiation. These intrinsic mechanisms were used as a framework for comparison and it was found that, in response to the light environment, developmental plasticity was elevated, resulting in two architectural strategies. This developmental plasticity concerns the growth direction and the size of the modules, the speed of their time-course changes, their branching and flowering. Under an open canopy, C. sericea rapidly develops large vertical structures and abundant flowering. This strategy leads the plant to be invasive by excluding competitors and disseminating in the landscape. In the understorey, C. sericea slowly develops long horizontal structures which creep across the soil surface, while assimilating structures are poorly developed. This strategy does not lead to invasiveness but may allow the plant to survive in the understorey and reach sunny patches.

Knee MR-arthrography in assessment of meniscal and chondral lesions.

INTRODUCTION: No study, so far in France, has investigated the diagnosis value of knee MR-arthrography since the recent approval of intra-articular gadolinium use, by this country's healthcare authorities. This study objective is to verify the MR-arthrography superiority on conventional knee MRI, in meniscus and cartilage knee lesions diagnosing accuracy both in regard to sensitivity and specificity. HYPOTHESIS: MR-arthrography, represents in some pathologic situations, a more accurate source of information than conventional MRI. MATERIALS AND METHODS: Over a 27 months period, 25 patients, scheduled to undergo a knee arthroscopy volunteered, after having been fully informed of the possible interest and risk of the MR-arthrography examination, to participate in this study. Twenty-one of them were finally included since in four cases the surgical indication was not confirmed. The group consisted of 15 males and six females with an average age of 35.7 years. All of them consecutively underwent conventional MRI, MR-arthrography finally followed by arthroscopy. The MRI and MR-arthrograms results were compared to the arthroscopy findings using the nonparametric Kappa test. RESULTS: To diagnose meniscal tears, statistical agreement measure for MRI with arthroscopy was good (K=0.69) but not as good as the MR-arthrography/arthroscopy agreement which, by itself was excellent (K=0.84). As a diagnosis tool, the sensitivity and specificity of MR-arthrography (respectively 100 and 89.6%) were much higher than the corresponding values observed in conventional MRI (92.3 and 82.8%, respectively) which nonetheless remain satisfactory. The meniscal tears characterization seemed to be better interpreted using MR-arthrography. As far as the chondral lesions in this series, they were predominantly located on the patellar surface and in the medial femorotibial compartment. For diagnosing the latter, the MRI/arthroscopy agreement was good (K=0.70) but not as good as the MR-arthrography/arthroscopy agreement (K=0.805) which can be rated excellent. The detection sensitivity thus increased by 10% with gadolinium intra-articular injection. However, assessment accuracy of the lesions depth was mediocre, with frequent errors for the intermediary stages. DISCUSSION: Intra-articular gadolinium injection improved MRI performances for numerous reasons: filling the joint, reinforcing the synovial fluid signal, and enhancing anatomic structures contrast on the T1-weighted sequences images. In this study, MR-arthrography appeared to be superior to conventional MRI in meniscal and cartilaginous lesions diagnosis, confirming the results previously obtained in other countries. In light of these results and other data from the literature, MR-arthrography can be indicated as an alternative to CT-arthrography in various clinical situations: detection of recurrent tears on operated menisci, search for cartilaginous lesions or foreign bodies in the joint space, and preoperative assessment before chondral repair procedures. However, conventional MRI remains the reference examination for studying cartilage, because the low resolution of MR-arthrography limits its performances in quantitative assessment of lesions depth.

Notch1 antiapoptotic activity is abrogated by caspase cleavage in dying T lymphocytes.

Excessive signaling via the Notch1 receptor inhibits apoptosis in T lymphocytes. Since several antiapoptotic proteins are cleaved by caspases during cell death, we investigated whether Notch1 was a caspase substrate. Results demonstrate that the intracellular domain of Notch1 (NICD) is cleaved into six fragments during apoptosis in Jurkat cells or peripheral T lymphocytes. Notch1 cleavage is prevented by the caspase inhibitors DEVD-fmk and VEID-fmk or by Bcl-2 expression. Caspase-3 and caspase-6 cleave the NICD into six fragments using sites located within the NF-kappaB binding domain, the ankyrin repeats and the transactivation domain. Notch1 cleavage correlates with the loss of HES-1 expression in apoptotic T cells. Notch1 fragments cannot inhibit activation-induced cell death in a T-cell hybridoma, confirming the abrogation of Notch1 antiapoptotic activity by caspases. The ability of the NICD but not the fragments to antagonize Nur77 activity supports a role for this factor in Notch1 antiapoptotic function.

[Thoracic sympathectomy: treatment for hyperhidrosis]. / Sympathectomie thoracique: un traitement de l'hyperhidrose.

Hyperhidrosis is a benign functional anomaly which is highly stressful for the patient. Active management is required. Several medical options are available but are often ineffective. The thoracic sympathic system plays a fundamental role in propagating stimulation of sudoral gland secretion. Endoscopic thoracic sympatecomy thus provides a radical treatment for severe palmar and axillary hyperhidrosis. We describe the technique used in our unit and present results and possible complications. This method has been used by many teams for several Years and despite some differences, most confirm major patient benefit. Phenomena of transferred sudation are frequent by are usually not invalidating. Patients should however be informed of this possibility because the effect is often irreversible.

Demographic analysis of tree colonization in a 20-year-old right-of-way.

Past tree colonization dynamics of a powerline-right-of-way (ROW) corridor in the Haut-Saint-Laurent region of Quebec was studied based on the present age distribution of its tree populations. This colonization study spans 20 years, from 1977 (ROW clearance) to 1996. The sampled quadrats were classified into six vegetation types. Tree colonization dynamics were interpreted in each type, and three distinct patterns were identified. (1) Communities adapted to acidic conditions were heavily colonized by Acer rubrum, at least for the last 12 years. (2) Communities adapted to mesic or to hydric conditions were more intensely colonized in the period 1985-1987 than in the following 9 years; this past success in tree colonization may have been caused by herbicide treatments, which could have facilitated tree establishment by damaging the herbaceous and shrub vegetation. (3) Cattail, vine-raspberry, and reed-dominated communities contained few tree individuals, with almost all trees establishing between 1979 and 1990; those three vegetation types appear as the most resistant to tree invasion in the ROW studied. This study supports the need for an integrated approach in ROW vegetation management, in which the selection of vegetation treatment methods would depend on the tree colonization dynamics in each vegetation type. Minimizing disturbances inflicted on ROW herbaceous and shrub covers should be the central strategy because disturbances jeopardize natural resistance to future tree invasion, except in communities adapted to acidic conditions where the existing vegetation does not prevent invasion by A. rubrum. Many trees are surviving the successive cutting operations by producing new sprouts each time, particularly in communities adapted to mesic and hydric conditions. In these cases, mechanical cutting should be replaced by a one-time stump-killing operation, to avoid repeated and unsuccessful treatments of the same individuals over time.

RESEARCH: Shrub Propagation Techniques for Biological Control ofInvading Tree Species

/ The use of relatively stable shrub communities to control invasionby trees could be an efficient way of reducing herbicide applications, andthus represents an environmental gain, in areas such as rights-of-way. Thequestion is how to favor the expansion of these relatively stable shrubcommunities using different propagation techniques. Three experimentaltreatments, cutting back, layering, and cutting back-layering were performedon Cornus stolonifera, Salix petiolaris, and Spiraea albaclones already located within the corridor of an electrical power line. Toestablish the efficiency of treatments, we examined the statisticaldifferences of growth traits between species and treatments.An analysis of the effects of layering shows, after the first growth season,differences for all growth traits in only one species, Spiraea alba.After the second growth season, we observed the development of new aerialstems. Layering favors horizontal expansion of shrubs over heightdevelopment. The third year after treatment, the effect of layering isreduced except for Cornus stolonifera, which continuously increases,as shown by the significant progression of the clone issued from the layereven five years after treatments. With the cutting back technique, weexpected a distinct vertical growth of the shrubs at the expense ofincreasing the crown diameter. This technique would be best associated withthe rejuvenation of clones, followed by a layering of new shoots to allow ahorizontal expansion of the shrubs. Therefore, the formation of a dense shrubcommunity by layering should be considered a valuable approach for thebiological control of undesirable trees in powerline rights-of-way.KEY WORDS: Layering; Cutting back; Right-of-way; Cornus stolonifera;Salix petiolaris; Spiraea alba; Quebec

Quantitative comparison of prone and supine myocardial SPECT MIBI images.

The myocardial count distribution and the stress/rest ratio distribution were compared between prone and supine Tc-99m MIBI myocardial SPECT acquisitions. Ninety-nine male patients with a low stress supine inferior wall count underwent stress and rest acquisitions in the supine and prone positions successively. For each study, values depicting the inferior, anterior, septal, and lateral wall counts were extracted from a medioventricular normalized circumferential profile and underwent a statistical analysis (Student's paired t-test). On prone imaging, when compared to supine imaging, counts showed a highly significant mean relative increase of 11% +/- 1% in the inferior wall and of 7% +/- 1% in the septum. Conversely, these counts showed a significant mean relative decrease of 4% +/- 1% in the anterior wall and of 3% +/- 1% in the lateral wall. Moreover, the inferior wall stress/rest ratio showed a highly significant mean relative increase (6% +/- 2%). The prone position is probably preferable for interpreting the inferior wall and septum, where relative counts are enhanced, as with TI-201, and because the inferior stress-rest discrepancies are reduced in that position. But the anterior and lateral wall information is impaired in the prone position. The authors suggest, in case of a low stress supine inferior count, the combination of both positions, which is feasible with Tc-99m MIBI, in order to prevent a misleading interpretation.

Impaired response of activated mononuclear phagocytes to interleukin 4 in inflammatory bowel disease.

BACKGROUND/AIMS: In inflammatory bowel disease (IBD), peripheral monocytes and intestinal macrophages show an increased state of priming and activation. The aim of this study was to test the hypothesis that the response of IBD mononuclear phagocytes to the contrainflammatory cytokine interleukin (IL) 4 may be altered. METHODS: The in vitro secretion of proinflammatory cytokines (IL-1 beta, tumor necrosis factor alpha [TNF-alpha], and IL-1-receptor antagonist [IL-1ra]) by peripheral monocytes and by intestinal lamina propria mononuclear cells (LPMNCs) was assessed by enzyme-linked immunosorbent assay. In parallel, superoxide anion release, macrophage mannose receptor, and IL-4 receptor expression were investigated. RESULTS: IBD peripheral monocytes and intestinal LPMNCs in vitro secrete increased amounts of proinflammatory cytokines (IL-1 beta and TNF-alpha) with decreased IL-1ra/IL-1 beta ratios. IL-4 down-regulates proinflammatory cytokine (IL-1 beta and TNF-alpha) and superoxide anion secretion in a dose-dependent manner. In contrast to normal and disease-specific controls, IBD peripheral monocytes and IBD intestinal LPMNCs show a diminished responsiveness to the inhibitory effect of IL-4. The IL-1ra/IL-1 beta ratios in normal monocytes are increased by IL-4, whereas in IBD monocytes low IL-1ra/IL-1 beta ratios persist after IL-4 treatment. IL-4-induced expression of macrophage mannose receptor, which is a molecule pivotal to macrophage-mediated host defense, again appeared to be impaired in IBD monocytes. CONCLUSIONS: IL-4-mediated regulation of mononuclear phagocyte effector functions is disturbed in IBD.

Shape preserving three-dimensional display of myocardial scintigraphic data.

A three-dimensional display has been developed which is specifically suited to the visualization of myocardial single photon emission tomographic (SPET) data. A set of radial maxima voxels, representative of the whole left ventricle uptake and shape is first extracted by cylindrical and spherical sampling of the short axis slices. A three-dimensional representation of these voxels is then obtained, with hues depicting the uptake amount and shades (i.e. intensity and saturation) depicting the shape. This technique is suitable for 201Tl and 99TCm-hexakis-2-methoxyisobutyl isonitrile (99TCm-sestamibi) myocardial images. It is proposed as an aid to interpreting myocardial SPET as it enables the physician to distinguish simultaneously the actual shape, the extent and the severity of perfusion defects on a single frame.

Cigarette smoking and peripheral arterial occlusive disease.

BACKGROUND: The importance of cigarette smoking in the etiology of peripheral arterial occlusive disease is well known, but there have been few studies that have quantified this relationship. METHODS: A case-control study design was used in which the case subjects were men with a history of claudication for at least 1 year and abnormal findings on noninvasive blood flow studies or on arteriography; control subjects were men attending the same hospital for conditions other than cancer, with no history of cancer or vascular disease and with a normal ankle-brachial index. Case and control subjects were interviewed by a trained nurse interviewer using a pilot-tested questionnaire. Current smoking status was confirmed by serum cotinine level estimation. Univariate odds ratios for smoking and other potential risk factors were calculated, and their significance was tested by comparison with the chi-squared distribution. Logistic regression analysis was used to adjust the effect of smoking for confounding variables, and the regression equation was used to estimate the proportion of disease attributable to smoking. RESULTS: Of the patients approached, 94% of the eligible case subjects and 93% of the eligible control subjects agreed to participate. Recruitment ended with 102 cases of peripheral arterial occlusive disease and 99 controls. Most of the control subjects were attending clinics for other surgical specialties. Compared with men who had never smoked the relative risk was 7 for exsmokers and 16 for current smokers (p < 0.001). The relative risk increased directly with the lifetime number of cigarettes smoked, the chi-squared test for trend being highly significant (p < 0.001). Age, lipoprotein concentration, body mass index, and history of hypertension or heart disease were also significant risk factors. CONCLUSIONS: After adjustment for confounding variables the estimate of the fraction of disease attributable to smoking was 76%.