Biomedical subjects

Lynne Moore

Publications and source records attributed to Lynne Moore.

18 recordsLinked to original sources

PubMed2006

Statistical validation of the Glasgow Coma Score.

BACKGROUND: To validate the predictive value of the Glasgow Coma Score (GCS) and find the best way to model the score in a logistic regression model predicting mortality. METHODS: Analyses were based on 20,494 patients from the trauma registries of three urban Level I trauma centers in the province of Quebec, Canada. The predictive value of the GCS and its components was evaluated in logistic regression models predicting in-hospital mortality with measures of discrimination and calibration. The performance of the GCS with no transformation and as an ordered categorical variable was compared with two transformation techniques: fractional polynomials and spline regression. RESULTS: The GCS had excellent discrimination (area under Receiving Operator Characteristic Curve=0.833 95% confidence interval=0.820-0.846) but fairly poor calibration (Pearson's Chi-squared statistic=122 on 11 df). The eye component added no predictive information to the verbal and motor components in the whole sample but was important in certain sub-populations. Using the three components separately, rather than the sum, did not improve the predictive model. Fractional polynomial transformation of the GCS improved calibration and spline regression performed even better. GCS modeled as an ordered categorical variable performed badly both in terms of discrimination and calibration. CONCLUSIONS: The GCS in its present form is an efficient predictor of in-hospital mortality, which could benefit from statistical transformation in logistic regression models when the accuracy of estimated probabilities of mortality is important. The common use of GCS categories for modeling mortality leads to loss of information and should be discarded.

Aged↗

PubMed2006

Paying the price of excluding patients from a trauma registry.

BACKGROUND: The goal of this study was to evaluate the impact of different trauma registry exclusion criteria on the assessment of trauma populations and outcome. METHODS: All patients admitted to a Canadian regional trauma center from April 1, 1993 to March 31, 2002 with a diagnosis of trauma (ICD-9 codes 800 to 959) were reviewed. TOTAL included everyone. REGISTRY included only patients meeting any of four criteria: death during hospital stay, transfer received from another hospital, admission to the intensive care unit, or hospital stay of 3 days or more. NOHIP excluded patients with isolated hip fracture. REG/NOHIP combined both. ISS12 and ISS15 excluded patients with ISS <12 and 15, respectively. RESULTS: There were 6,839 trauma patients. The percentage of excluded patients by group was: REGISTRY, 21.2%; NOHIP, 14.7%; REG/NOHIP, 34.9%; ISS12, 75%; and ISS15, 80.3%. Median length of stay was 7 days. Exclusions represented a total number of hospitalization days varying from 1.9% to 65.5% of TOTAL. Mortality was 6.9% for TOTAL, 8.6% for REGISTRY (p < 0.001), 5.7% for NOHIP (p = 0.009), 7.5% for REG/NOHIP (p=NS), 16.1% for ISS12 (p < 0.001), and 20.4% for ISS15 (p < 0.001). In groups with exclusions, transfer to long-term care varied from 0.14% to 23.5% in the excluded patients. For rehabilitation, these percentages varied from 0.14% to 17.6%. CONCLUSIONS: Registry exclusion criteria significantly alter the apparent severity of injury and resource utilization. The use of divergent exclusion criteria in the analysis of trauma registry data may be misleading.

Adult↗

PubMed2006

Unification of the revised trauma score.

BACKGROUND: The Revised Trauma Score (RTS) calculated with Major Outcome Trauma Study weights (MTOS-RTS) is currently the standard physiologic severity score in trauma research and quality control. It is often confused with the Triage-RTS (T-RTS), a version that is easier to calculate but only intended for clinical triage. OBJECTIVES: To compare the accuracy of the MTOS-RTS to the RTS calculated with weights derived from the study population (POP-RTS) and the T-RTS, for predicting mortality in a trauma population. METHODS: The study population consists of 22,388 patients, drawn from the trauma registries of three Level I trauma centers. The predictive accuracy of the MTOS-RTS, POP-RTS, and the T-RTS were compared using measures of discrimination and model fit from logistic regression models. RESULTS: The MTOS-RTS, the POP-RTS, and the T-RTS had the same discrimination (Area under the Receiver Operating Curve [AUC] = 0.841). The POP-RTS and the T-RTS had a slightly better model fit than the MTOS-RTS (AIC = 8010, 8010, and 8067, respectively). The T-RTS had equal discrimination and equal or better model fit than the MTOS-RTS in the whole sample, in each of the three trauma centers and in the population of patients with severe head trauma. The T-RTS was also equivalent to the POP-RTS in all of these population sub-groups. CONCLUSIONS: The T-RTS could replace the MTOS-RTS as the standard physiologic severity score for trauma outcome prediction. The advantages of using the T-RTS over the MTOS-RTS are ease of calculation, the need for only one measure for triage and mortality prediction purposes and universal adaptation to a broad range of trauma populations.

Aged↗

PubMed2006

Two worst injuries in different body regions are associated with higher mortality than two worst injuries in the same body region.

BACKGROUND: The Injury Severity Score (ISS) accounts for only one injury in each body region. The New Injury Severity Score (NISS) considers all injuries in a body region. Despite a big difference between the two scores in patients with multiple injuries, the NISS does not offer significant improvement in mortality prediction. This paper hypothesizes that two injuries in different body regions are associated with higher mortality than two injuries in the same body region, independently of injury severity. METHODS: The population consisted of 15,200 patients with two or more injuries from the Quebec Trauma Registry, Canada, abstracted between 1998 and 2004. The two worst injuries were considered. Logistic regression analysis was used to assess the mortality odds ratio of having two worst injuries in different body regions (DR) compared with two worst injuries in the same body region (SR), while adjusting for the severity and the body region of the two worst injuries and age. RESULTS: A total of 5,869 patients (49%) had their worst injuries in DR. DR patients had 75% higher risk of mortality than SR patients (odds ratio = 1.75, 95% confidence interval = 1.42-2.15). CONCLUSION: After accounting for differing injury severity, patients with their two worst injuries in different body regions have higher mortality than those with their two worst injuries in the same region. Results suggest that the observed effect is not due to a foible in the Abbreviated Injury Scale system but rather to physiologic, clinical, or organizational elements. The results of this study should be considered in the development of future injury severity instruments and may have implications for the care of patients with multiple injuries.

Aged↗

PubMed2006

Statistical validation of the Revised Trauma Score.

BACKGROUND: To validate the accuracy of the Revised Trauma Score (RTS) and its components for predicting in-hospital mortality. METHODS: Analyses were based on 22,388 patients from the trauma registries of three urban Level I trauma centers in the province of Quebec, Canada. The accuracy of RTS coded variables for the Glasgow Coma Score (GCSc), Systolic Blood Pressure (SBPc), and Respiratory Rate (RRc) for predicting mortality was evaluated in logistic regression models with measures of discrimination and model fit and compared with Fractional Polynomial (FP) transformations of each component. RESULTS: RTS coded variables were associated with sparse data distributions and did not accurately represent the relation of GCS, SBP, and RR to mortality. FP models were always associated with significantly better discrimination (all p < 0.00001) and model fit. Survival probability estimates generated by the model with FP transformations were significantly different to those generated by the model with RTS-coded variables. CONCLUSIONS: The RTS in its present form does not accurately describe the relation of GCS, SBP, and RR to mortality. FP transformation would improve the accuracy of predicted survival probabilities used for performance evaluation and may improve control of confounding caused by of physiologic severity case mix in trauma research.

Adolescent↗

PubMed2006

Is the delay to surgery for isolated hip fracture predictive of outcome in efficient systems?

BACKGROUND: Adverse outcomes for patients with isolated hip fracture have been documented when preoperative delay is longer than 48 hours. An efficient system will have the capacity to repair all hip fractures within 48 hours. We hypothesized that in an efficient system, there would be a medical justification for a delay greater than 48 hours. The purpose of this study was to identify the causes and outcome of delay for hip surgery in an efficient system. METHODS: All patients with isolated hip fracture admitted to a regional trauma center from April 1993 to March 2003 were reviewed. Demographics, presence of comorbidity, preoperative delay, complications, and mortality were collected. Univariate and multivariate analysis were carried out. RESULTS: The cohort included 977 patients. Overall mortality was 12.2%. Surgery was performed within 24 hours in 53% of cases and within 48 hours in 87% of cases. The presence of comorbidity partly explained longer (>48 hours) surgical delays. Multivariate analysis revealed that age greater than 65, male sex, and the presence of pulmonary and cardiac comorbid conditions or an active cancer but not surgical delay were associated with mortality and complications. However, surgical delay was associated with longer postsurgical hospital stay, independently of the presence of comorbidity or increasing age. CONCLUSIONS: Preoperative delay does not entail adverse outcomes when the surgery is delayed to allow for treatment of comorbid medical conditions. Preoperative delay is associated with a longer hospital stay. The presence of comorbidity only partly explains preoperative delay and adverse outcomes. A prospective study coding for the severity of comorbid conditions and the justification of the preoperative delay will be required to fully elucidate the link between delay and outcome.

Adult↗

PubMed2006

Consensus or data-derived anatomical severity scoring?

We aimed to compare the predictive accuracy of consensus-derived and data-derived injury severity scores when considered alone and in combination with age and physiological status. Analyses were based on 25,111 patients. The predictive validity of each severity score was evaluated in logistic regression models predicting in-hospital mortality using measures of discrimination and calibration. Data-derived scores had consistently better predictive accuracy than consensus-derived scores in univariate models (p<0.0001) but very little difference between scores was observed in models including information on age and physiological status. Data-derived scores provide more accurate mortality prediction than consensus-derived scores when only anatomic injury severity is considered but offer little advantage if age and physiological status are taken into account.

Adolescent↗

PubMed2005

The Injury Severity Score or the New Injury Severity Score for predicting intensive care unit admission and hospital length of stay?

OBJECTIVES: To compare the New Injury Severity Score (NISS) and the Injury Severity Score (ISS) as predictors of intensive care unit (ICU) admission and hospital length of stay (LOS) in an urban North American trauma population and in a subset of patients with head injuries. METHODS: The study population consisted of 23,909 patients from three urban level I trauma centres in the province of Quebec, Canada. The predictive accuracies of the NISS and the ISS were compared using Receiver Operator Characteristic (ROC) curves and Hosmer-Lemeshow (H-L) statistics for the logistic regression model of ICU admission and using r2 for the linear regression model of LOS. RESULTS: A total of 7660 (32%) patients were admitted to the ICU. Mean LOS was 8.2+/-2.5 days. In the whole sample, the NISS presented equivalent discrimination (area under ROC curve: NISS = 0.839 versus ISS = 0.843, p = 0.08) but better calibration (H-L statistic: 309 versus 611) for predicting ICU admission. In the subgroup patients with moderate to serious head injuries, the NISS was a better predictor of ICU admission in terms of both discrimination (area under ROC curve: NISS = 0.771 versus ISS = 0.747, p < 0.00001) and calibration (H-L statistic: 12 versus 21). The NISS explained more variation in LOS than the ISS for the whole sample (r2 = 0.254 versus 0.249, p = 0.0008) and in the sub-population with moderate to severe head injuries (r2 = 0.281 versus 0.263, p = 0.0002). CONCLUSIONS: The NISS is a better choice for case mix control in trauma research than the ISS for predicting ICU admission and LOS, particularly among patients with moderate to severe head injuries.

Adolescent↗

PubMed2005

A second injury in the same body region is associated with lower mortality than a second injury in a different body region.

HYPOTHESIS: A second injury in the same body region is associated with lower mortality than a second injury in a different body region, independently of injury severity and body region. METHODS: The population consisted of 15,200 patients with two or more injuries from level I trauma centers in Quebec. The mortality odds ratio of having a same-region second injury (SR) as opposed to a different-region second injury (DR) was assessed. RESULTS: Patients with a SR had 43% lower odds of mortality when compared to patients with a DR. CONCLUSION: A second injury in the same body region is associated with lower mortality than a second injury in a different body region.

Accidents, Traffic↗

PubMed2005

Comorbidity and age are both independent predictors of length of hospitalization in trauma patients.

BACKGROUND: Length of hospitalization is a good indicator of resource utilization. Older patients are increasingly suffering trauma, and comorbid medical conditions are also increasing. Our objective was to determine the separate and combined effect of these 2 factors on length of hospital stay for trauma patients in a tertiary trauma centre. METHODS: All 994 consecutive trauma patients surviving to hospital discharge between Apr. 1, 2000, and Mar. 31, 2001, were identified. Patient characteristics, injury severity and length of hospitalization were obtained from the hospital trauma registry. Each medical record was then reviewed for completeness of information and assessment of comorbid conditions. A multivariate linear regression model was developed to predict logarithmic length of stay from age and presence of a cormorbid condition while adjusting for the Injury Severity Score (ISS). RESULTS: The mean age of the patients was 49.7 (range from 14-100) years and median ISS was 9 (range from 1-50). At least 1 comorbid condition was present in 321 (32%) patients. Mean length of hospital stay was 15.3 days. The proportion of patients with a comorbid condition increased steadily with age, from 8.7% before the age of 55 years to 92% at 85 or more years of age (p < 0.001). According to the multivariate model, the presence of comorbidity, age and ISS were all independent predictors of hospital stay (p < 0.001). When applied to patients with the mean ISS value of 9, the model showed an increase in length of hospitalization for patients with a comorbid condition over those without; (3.6 v. 13.1 d for patients < 55 and > or = 85 yr respectively). Length of hospital stay increased particularly with neurologic and pulmonary problems. CONCLUSIONS: Comorbidity and age were both independently significant predictors of length of hospitalization over and beyond that which is expected based on the severity of the injuries. With an aging population, this phenomenon should severely affect resource utilization in trauma centres in the near future. Researchers should take account of both age and comorbidity in order to compare trauma populations.

Adolescent↗

PubMed2005

Multiple imputation of the Glasgow Coma Score.

BACKGROUND: To investigate whether multiple imputation (MI) of missing Glasgow Coma Scale (GCS) values generates more accurate GCS frequency distributions and less biased parameter estimates in logistic regression models predicting mortality than the standard procedure of excluding observations with missing GCS values. METHODS: The study population consisted of 5,065 patients with complete GCS information from the trauma registry of a Level 1 trauma center. Missing GCS values were imposed on the data set, and the performance of MI (extrapolating missing GCS from a data prediction model) and of deleting all data observations with missing GCS (list-wise deletion) were evaluated. GCS and Trauma and Injury Severity Score (TRISS) frequency distributions and parameter estimates were compared with true values from the original data set. RESULTS: GCS and TRISS frequency values generated by MI were much more accurate than those generated by list-wise deletion. GCS and TRISS parameter estimates generated by MI all had acceptable bias and coverage rates when compared with true values. List-wise deletion provided biased parameter estimates for the GCS, the Revised Trauma Score, and the Injury Severity Score. CONCLUSION: MI is a valid solution to the problem of missing GCS data in trauma research. It allows the conservation of precious data observations and leads to unbiased estimates in consequent analyses. Analyses, which exclude observations with missing GCS data, provide biased results.

Biomedical Research↗

PubMed2004

Preinjury warfarin use among elderly patients with closed head injuries in a trauma center.

BACKGROUND: This study aimed to determine the impact of warfarin use on the severity of injury among elderly patients presenting with closed head injuries. METHODS: A cohort of patients 55 years of age or older with closed head injuries taken to a tertiary trauma center between April 1993 and March 2001 was retrospectively identified. Patient characteristics, mechanism of injury, type and severity of injury, and hospital survival data were obtained from the trauma registry. Each case then was reviewed for completeness of information, assessment of preinjury warfarin use, and comorbidity. RESULTS: Among the 384 patients presenting with closed head injuries, 35 (9%) were receiving warfarin before their trauma. As compared with nonusers, anticoagulated patients had a higher frequency of isolated head trauma (54% vs. 32%; p = 0.008), more severe head injuries (65.7% vs. 44.1%; p = 0.02), and a higher rate of mortality (40% vs. 21%, p = 0.01). These associations remained evident even after population differences in age, gender, comorbidities, and mechanism of injury were taken into account. Indeed, according to multivariate logistic regression models, warfarin use was associated with a statistically significant risk of death (odds ratio [OR], 2.73; 95% confidence interval [CI], 1.22-6.12), statistically significant odds for more severe head injury (OR, 2.39; 95% CI, 1.10-5.17), and odds for isolated head injury that almost reached statistical significance (OR, 1.79; 95% CI, 0.82-3.90). CONCLUSIONS: Among patients 55 years of age or older who present with closed head injury, the use of warfarin before trauma appears to be associated with a higher frequency of isolated head trauma, more severe head trauma, and a higher likelihood of death. The findings of this retrospective study support the concern about the adverse effects of anticoagulants in cases of head trauma.

Aged↗

PubMed2004

The New Injury Severity Score: a more accurate predictor of in-hospital mortality than the Injury Severity Score.

OBJECTIVE: The purpose of this study was to determine whether the New Injury Severity Score (NISS) is a better predictor of mortality than the Injury Severity Score (ISS) in general and in subgroups according to age, penetrating trauma, and body region injured. METHODS: The study population consisted of 24,263 patients from three urban Level I trauma centers in the province of Quebec, Canada. Discrimination and calibration of NISS and ISS models were compared using receiver operator characteristic (ROC) curves and Hosmer-Lemeshow statistics. RESULTS: NISS showed better discrimination than ISS (area under the ROC curve = 0.827 vs. 0.819; p = 0.0006) and improved calibration (Hosmer-Leme-show = 62 vs. 112). The advantage of the NISS over the ISS was particularly evident among patients with head/neck injuries (area under the ROC curve = 0.819 vs. 0.784; p < 0.0001; Hosmer-Lemeshow = 59 vs. 350). CONCLUSION: The NISS is a more accurate predictor of in-hospital death than the ISS and should be chosen over the ISS for case-mix control in trauma research, especially in certain subpopulations such as head/neck-injured patients.

Adolescent↗

PubMed2003

Dosage, duration and timing of nonsteroidal antiinflammatory drug use and risk of prostate cancer.

Experimental studies suggest that NSAIDs could reduce prostate cancer risk. Results of observational studies on the relation between NSAIDs and prostate cancer risk have, however, been inconsistent. Moreover, none has addressed the issues of dosage, duration and timing of exposure. In a population-based, age-matched case-control study, we measured the association between prostate cancer risk and NSAIDs defined in terms of mean daily dose, cumulative duration and timing of exposure. Eight-year drug exposure history was obtained from the Quebec health insurance system database. Parallel analyses were performed for aspirin and NSAIDs other than aspirin. We controlled for detection bias and assessed the potential impact of protopathic bias. Analyses were performed with conditional logistic regression. Among the 2,221 cases and 11,105 controls, there was a negative trend between cumulative duration of aspirin use and prostate cancer risk (p = 0.0009). Also, exposure to a mean daily dose of aspirin of at least 80 mg, maintained throughout the entire 8 years of follow-up, was associated with an 18% reduction in prostate cancer risk (OR = 0.82, 95% CI 0.71-0.95). In more recent users of such a dose, the risk reduction was 7%. However, 1 year after the end of a 7-year regular aspirin exposure, no residual protective effect persisted. No association was observed between prostate cancer risk and exposure to NSAIDs other than aspirin. The results suggest that long-term and regular use of aspirin, at a dosage beneath that usually recommended for an anti-inflammatory effect, may prevent prostate cancer.

Aged↗

PubMed2003

Elderly trauma patients with rib fractures are at greater risk of death and pneumonia.

BACKGROUND: The purpose of this study was to show that elderly patients admitted with rib fractures after blunt trauma have increased mortality. METHODS: Demographic, injury severity, and outcome data on a cohort of consecutive adult trauma admissions with rib fractures to a tertiary care trauma center from April 1, 1993, to March 31, 2000, were extracted from our trauma registry. RESULTS: Among 4,325 blunt trauma admissions, there were 405 (9.4%) patients with rib fractures; 113 were aged > or = 65. Injuries were severe, with Injury Severity Score (ISS) > or = 16 in 54.8% of cases, a mean hospital stay of 26.8 +/- 43.7 days, and 28.6% of patients requiring mechanical ventilation. Mortality (19.5% vs. 9.3%; p < 0.05), presence of comorbidity (61.1% vs. 8.6%; p < 0.0001), and falls (14.6% vs. 0.7%; p < 0.0001) were significantly higher in patients aged > or = 65 despite significantly lower ISS (p = 0.031), higher Glasgow Coma Scale score (p = 0.0003), and higher Revised Trauma Score (p < 0.0001). After adjusting for severity (i.e., ISS and Revised Trauma Score), comorbidity, and multiple rib fractures, patients aged > or = 65 had five times the odds of dying when compared with those < 65 years old. CONCLUSION: Despite lower indices of injury severity, even after taking account of comorbidities, mortality was significantly increased in elderly patients admitted to a trauma center with rib fractures.

Aged↗

PubMed2002

Effect of treatment delay on outcome of patients with early-stage head-and-neck carcinoma receiving radical radiotherapy.

PURPOSE: Access to radiotherapy (RT) has been considerably reduced in Quebec since the late 1980s. The aim of the present study was to analyze the impact of delaying treatment on the outcome of patients with early head-and-neck squamous cell carcinomas. MATERIALS AND METHODS: This retrospective analysis examined the outcome for all 623 patients with early-stage disease (T1-2, N0-1) who received radical RT between 1988 and 1997 at the Hotel Dieu of Quebec Hospital. Delay was defined as the time from initial evaluation by a radiation oncologist to the beginning of RT. Delay intervals were divided as follows: <30 days, 31-40 days, and >40 days. RESULTS: A delay of >40 days was significantly associated with an increased risk of local and neck failure and poorer survival relative to patients treated in <30 days or between 31 and 40 days. The adjusted hazard ratio and (in parentheses) the 95% confidence interval was 2.6 (1.07-6.4), 2.73 (1.38-5.4), and 1.7 (1.1-2.6), respectively, for local failure, neck failure, and survival. In the subgroup of patients with T2N0 disease, delaying RT for >30 days was associated with a poor outcome, as measured by the same end points. CONCLUSION: Delaying RT had a deleterious effect on these patients. RT should be started as soon as possible in patients with squamous cell carcinoma of the head and neck, preferably within 20-30 days after evaluation by a radiation oncologist.

Aged↗

PubMed2002

PSA screening and prostate cancer mortality.

BACKGROUND: Physicians have speculated that prostate-specific antigen (PSA) screening may be responsible for the reduction in prostate cancer mortality observed in the late 1 990s. In order to test this hypothesis, we assessed the relation between the change in prostate cancer incidence in the early 1990s, attributed largely to PSA screening, and the subsequent change in prostate cancer mortality. METHODS: We divided the adult male population of Quebec aged 50 years and more into 15 birth cohorts. For each birth cohort, we computed the change in prostate cancer incidence between 1989 and 1993 and the change in prostate cancer mortality between 1995 and 1999. We then assessed the correlation between the changes in prostate cancer incidence and the subsequent changes in prostate cancer mortality by weighted linear regression. We also split up the study population into 15 regional populations and repeated the analysis described above. RESULTS: We found that even though most birth cohorts showed an increase in prostate cancer incidence and a subsequent decrease in mortality, the sizes of these changes were not inversely correlated (Pearson's r = 0.33, 1-sided p = 0.89). Similarly, in the regional population study, we found that a greater increase in prostate cancer incidence did not indicate a greater decline in mortality (Pearson's r= 0.13, 1-sided p = 0.68). INTERPRETATION: These results suggest that for our study population PSA screening was not associated with, and therefore cannot explain, the decline in prostate cancer mortality.

Aged↗

PubMed2002

[Prevalence of psychiatric disorders and factors associated with delirium in patients referred to a psycho-oncology service].

The charts of 628 cancer patients, referred to the psycho-oncology service at the Hôtel-Dieu de Québec from 1994 to 1997, were reviewed in 1997 to determine the nature, the prevalence, and the characteristics of psychiatric diagnoses, particularly delirium. Results showed that among patients diagnosed with a psychiatric disorder, 54.5% had adjustment disorders, 13.1% suffered from delirium and 10.9% from major depression. Statistically significant associations were observed between delirium and the use of opioids (odds-ratio (OR): 3.87, 95% confidence interval (CI) = 2.28-6.57), corticosteroids (OR = 4.33; CI = 2.34-8.08), a history of alcoholism (OR = 2.41; CI = 1.27-4.56), being hospitalized (OR = 6.10; CI = 2.85-13.08), and being older (OR = 1.06; CI = 1.04-1.08). These results confirm the high frequency of psychiatric disorders in patients referred for a consultation in psycho-oncology and underline the importance to develop such services. Delirium is a major psychiatric complication of cancer and is associated with opioids, corticosteroids, alcoholism, being hospitalized, and being older.

Adult↗