Rama C. Nair

A study to develop clinical decision rules for the use of radiography in acute ankle injuries

STUDY OBJECTIVE To develop decision rules that will predict fractures in patients with ankle injuries, thereby assisting clinicians in being more selective in their use of radiography. DESIGN Prospective survey of emergency department patients over a five-month period. SETTING Two university hospital EDs. PARTICIPANTS One hundred fifty-five adults in a pilot stage and 750 in the main study; all presented with acute blunt ankle injuries. INTERVENTIONS Thirty-two standardized clinical variables were assessed and recorded on data sheets by staff emergency physicians before radiography. MEASUREMENTS Variables were assessed for reliability by the kappa coefficient and for association with significant fracture on both ankle and foot radiographic series by univariate analysis. The data then were analyzed by logistic regression and recursive partitioning techniques to develop decision rules for predicting fractures in each radiographic series. MAIN RESULTS All 70 significant malleolar fractures found in the 689 ankle radiographic series performed were identified among people who had pain near the malleoli and were age 55 years or more, had localized bone tenderness of the posterior edge or tip of either malleolus, or were unable to bear weight both immediately after the injury and in the ED. This rule was 100% sensitive and 40.1% specific for detecting malleolar fractures and would allow a reduction of 36.0% of ankle radiographic series ordered. Similarly, all 32 significant midfoot fractures on the 230 foot radiographic series performed were found among patients with pain in the midfoot and bone tenderness at the base of the fifth metatarsal, the cuboid, or the navicular. CONCLUSION Highly sensitive decision rules have been developed and will now be validated; these may permit clinicians to confidently reduce the number of radiographs ordered in patients with ankle injuries.

The Burden of Chronic Kidney Disease in Renal Transplant Recipients

The National Kidney Foundation has developed guidelines for the diagnosis and classification of chronic kidney disease (CKD) but it is not known whether these are applicable to renal transplant recipients. This study determined the prevalence of CKD according to the stages defined in the guidelines, the complications related to CKD and whether the prevalence of complications was related to CKD stage in 459 renal transplant recipients. CKD was present in 412 patients (90%) and 60% were in CKD Stage 3 with a glomerular filtration rate (GFR) between 30 and 59 mL/min/1.73 m2. The prevalence of anemia increased from 0% in Stage 1 to 33% in Stage 5 (p < 0.001). Hypertension was present in 86% and increased from 60% in Stage 1 to 100% in Stage 5 (p = 0.02). The number of anti‐hypertensives per patient increased from 0.7 in Stage 1 to 2.3 in Stage 5 (p < 0.001). The number of CKD complications per patient increased from 1.1 in Stage 1 to 2.7 in Stage 5 (p < 0.001). We conclude that CKD and the complications of CKD are highly prevalent in renal transplant recipients. The classification of renal transplant patients by CKD stage may help clinicians identify patients at increased risk and target appropriate therapy to improve outcomes.

Renin-angiotensin system blockade and the risk of hyperkalemia in chronic hemodialysis patients

BACKGROUND Blockade of the renin-angiotensin system by angiotensin-converting enzyme (ACE) inhibitors or angiotensin receptor blockers can cause hyperkalemia in patients with chronic renal insufficiency who are not on dialysis, but the risk of hyperkalemia in hemodialysis patients is unknown. SUBJECTS AND METHODS We conducted a prospective study of 251 adult hemodialysis patients to determine if renin-angiotensin system blockade was associated with hyperkalemia, defined as a predialysis serum potassium concentration of 5.5 mmol/L or higher. Medication use was determined by chart review and patient interview. Predialysis serum potassium concentration was measured monthly. RESULTS There were 367 episodes of hyperkalemia during 1877 person-months of follow-up. After adjustment for potential confounding variables and for clustering of episodes by patient, use of an ACE inhibitor or an angiotensin receptor blocker was associated with a significantly higher risk of hyperkalemia (odds ratio [OR] = 2.2; 95% confidence interval [CI]: 1.4 to 3.4). The increased risk of hyperkalemia with renin-angiotensin system blockade was seen in anuric dialysis patients (OR = 2.3; 95% CI: 1.3 to 4.2), as well as those with residual renal function (OR = 2.1; 95% CI: 1.0 to 4.1). CONCLUSION The use of ACE inhibitors or angiotensin receptor blockers is independently associated with an increased risk of developing hyperkalemia in chronic hemodialysis patients. The serum potassium concentration should be closely monitored when these medications are prescribed for hemodialysis patients.

Factors influencing pandemic influenza vaccination of healthcare workers???A systematic review

INTRODUCTION Maintaining the health and availability of Health care workers (HCW) is an essential component of pandemic preparedness. A key to protecting HCW during the H1N1 pandemic was influenza vaccination. Numerous researchers have reported on factors influencing H1N1 vaccination behaviour in various HCW groups. This systematic review aims to inform future influenza vaccine interventions and pandemic planning processes via the examination of literature in HCW H1N1 vaccination, in order to identify factors that are (1) unique to pandemic influenza vaccination and (2) similar to seasonal influenza vaccination research. METHODS We conducted a comprehensive review of literature (MEDLINE, PubMed, EMBASE, PsycINFO, CINHAL, AMED, Cochrane Library, ProQuest, and grey literature sources) published between January 2005 and December 2011 to identify studies relevant to HCW pH1N1 vaccine uptake/refusal. RESULTS 20 publications sampling HCW from different geographic regions are included in this review. H1N1 vaccine coverage was found to be variable (9-92%) across HCW populations, and self-reported vaccine status was the most frequently utilized predictor of pandemic vaccination. HCW were likely to accept the H1N1 vaccine if they perceived, (1) the H1N1 vaccine to be safe, (2) H1N1 vaccination to be effective in preventing infection to self and others (i.e. loved ones, co-workers and patients), and (3) H1N1 was a serious and severe infection. Positive cues to action, such as the access of scientific literature, trust in public health communications and messaging, and encouragement from loved ones, physicians and co-workers were also found to influence HCW H1N1 uptake. Previous seasonal influenza vaccination was found to be an important socio-demographic predictor of vaccine uptake. Factors unique to HCW pandemic vaccine behaviour are (1) lack of time and vaccine access related barriers to vaccination, (2) perceptions of novel and rapid pandemic vaccine formulation, and (3) the strong role of mass media on vaccine uptake. CONCLUSIONS Many of the factors that influenced HCW pandemic vaccination decisions have previously been reported in seasonal influenza vaccination literature, but some factors were unique to pandemic vaccination. Future influenza vaccine campaigns should emphasize the benefits of vaccination and highlight positive cues to vaccination, while addressing barriers to vaccine uptake in order to improve vaccine coverage among HCW populations. Since pandemic vaccination factors tend be similar among different HCW groups, successful pandemic vaccination strategies may be effective across numerous HCW populations in pandemic scenarios.

Iridium-192 curietherapy for T1 and T2 epidermoid carcinomas of the floor of mouth

From 1970 to 1986, 117 patients with T1 (47) or T2 (70) epidermoid carcinomas of the floor of the mouth (SCC) were treated by iridium-192 implantation (192 Ir). The dose was prescribed according to the Paris System and varied over those years. Follow-up information was available on 116 patients. There were 46 T1N0, 47 T2N0, and 23 T2N1-3. Neck management varied for the 93 N0 patients consisting of surveillance (24 T1, 17 T2) or elective neck dissection (22 T1:all pN-, 30 T2: 20 pN-, 10 pN+). Cause specific survival rates were 94% for T1N0, 61.5% for T2N0, and 28% for T2N1-3 at 5 years. Primary local control was 93.5%, 74.5%, and 65%, respectively, and 98%, 79%, and 65% after salvage. Patients with gingival extension or a tumor size over 3 cm (T2b) had a local control of 50% (9/18) and 58% (15/26), respectively. Nodal control was 93.5% for Stage I, 85% for Stage II, and 48% for T2N1-3 patients. There was no difference in nodal control with regard to treatment policy for Stage I-II patients. There were few complications including three deaths: two from surgery and one from 192 Ir. Nodal status, tumor size defined as T1, T2a (less than or equal to 3 cm), T2b (greater than 3 cm), and gingival extension were the only independent prognostic factors. The management of T1N0 and T2N0 SCC by 192 Ir to a dose of 65 or 70 Gy, using the Paris System, is recommended for lesions 3 cm or less and without gingival extension.

Relative importance of risk factors in bladder carcinogenesis

Abstract Responses from outpatients with urological complaints were recorded in a detailed questionnaire exploring potential risk factors in bladder cancer. Subjects were subsequently classified on the basis of hospital records as cases or controls. Each of the 265 cases was matched to two controls of the same age and sex. History and treatment of tuberculosis of all subjects was verified through the four geographically adjacent tuberculosis registers. Analysis of exposures of matched triples revealed six statistically significant associations with bladder cancer in males (smoking, gout, allergies (self), allergies (family), occupational radiation exposure, and occupational exposure to chemicals) and, in females, one significant positive association (coffee consumption) and one significant negative association (allergies, self). Although the relative risk of INH exposure in females was the highest observed (3.0), the number of exposed individuals was too small to permit any meaningful conclusion. Discriminant analysis was used to rank the variables in order of their importance as potential risk factors. Statistically significant ability to discriminate cases from controls was observed in males for: (1) Allergy (family); (2) occupational exposure to radiation; (3) occupational exposure to chemicals, and (4) smoking. In females, significant discriminators were: (1) coffee consumption; (2) history of tuberculosis and INH treatment, and (3) allergy (self, protective effect). The suggestion of carcinogenic potential of a widely used prophylactic drug indicates that a large, rigorously conducted study of the association of INH with bladder cancer is in order.

Smoking and binge drinking among Canadian survivors of childhood and adolescent cancers: a comparative, population-based study.

Objectives of this study were to describe the prevalence of smoking and binge drinking among survivors of childhood and adolescent cancer compared to controls who had never had cancer, and to identify factors associated with these behaviors.

Does uncomplicated diverticular disease produce symptoms

A questionnaire dealing with bowel symptoms was administered to 97 outpatients referred for air-contrast barium enema. Subsequenlly, the barium enema was interpreted by a radiologist who did not know the results of the questionnaire. Forty-nine had normal x-rays, and 27 had uncomplicated diverticular disease. Weight loss, rectal bleeding, abdominal pain, and pain at night were as common in those with a normal examination as in those with diverticula. Symptoms of colon dysfunction included abdominal pain relieved by defecation, altered stool frequency and consistency with pain onset, abdominal distension, feeling of incomplete evacuation after defecation, and mucus in the stool. These were equally prevalent in both groups. Therefore, no symptoms could be ascribed to the presence of diverticula

Qualitative motivators and barriers to pandemic vs. seasonal influenza vaccination among healthcare workers: A content analysis

INTRODUCTION Influenza is a major concern across healthcare environments. Annual vaccination of healthcare workers (HCW) remains a key mode of influenza prevention in healthcare settings. Yet influenza vaccine coverage among HCWs continues to be below recommended targets, in pandemic and non-pandemic settings. Thus, the primary objective of this analysis is to identify motivators and barriers to pandemic (panINFLU) and seasonal influenza vaccination (sINFLU) through the qualitative analysis of HCW provided reasons driving HCWs personal vaccination decisions. METHODS Data were collected from a multi-professional sample of HCWs via a cross-sectional survey study, conducted at a tertiary-care hospital in Ontario, Canada. HCW provided and ranked qualitative reasons for personal (1) panINFLU (pH1N1) and (2) sINFLU (2008/2009 season) vaccine uptake and avoidance were used to identify key vaccination motivators and barriers through content analysis methodology. RESULTS Most HCW vaccination motivators and barriers were found to be similar for panINFLU and sINFLU vaccines. Personal motivators had the greatest impact on vaccination (panINFLU 29.9% and sINFLU 33.9%). Other motivators included preventing influenza in loved ones, patients, and community, and awareness of HCW role in influenza transmission. In contrast, concerns of vaccine safety and limited HCW knowledge of influenza vaccines (panINFLU 46.2% and sINFLU 37.3%). HCW vaccination during the pandemic was motivated by panINFLU related fear, epidemiology, and workplace pro-vaccination policies. HCW perceptions of accelerated panINFLU vaccine development and vaccine safety compromises, negative views of external sources (i.e. media, pharmaceutical companies, and regulatory agencies) and pandemic management strategies were barriers specific to panINFLU vaccine. CONCLUSIONS HCW panINFLU and sINFLU vaccine coverage can increase if future vaccination programs (1) highlight personal vaccination benefits (2) emphasize the impact HCW non-vaccination on family members, patients and community, (3) address HCW vaccine related knowledge gaps, and (4) implement pro-vaccination workplace policies consistent with those in place at the study site during pH1N1.

Combining social network analysis and cluster analysis to identify sexual network types.

Increases in the rates of sexually transmitted infections (STIs) suggest that control programmes may not be effectively targeting diverse subpopulations. The objective of this investigation was to examine STI transmission within different groups, using both social network analysis and cluster analysis. Routine partner notification data were analysed from individuals diagnosed with, or exposed to an STI in Manitoba. Groups were identified and characterized. Three different clusters of groups were identified, comprised of demographically and clinically distinct individuals. A greater understanding of disease transmission patterns within these groups will aid in the development of targeted education and prevention programmes for all STIs.