Validity of the NIHSS in predicting arterial occlusion in cerebral infarction is time-dependent.

BACKGROUND: The NIH Stroke Scale (NIHSS) is used to assess acute ischemic stroke severity and outcome. High NIHSS scores are usually associated with arterial occlusion but it is unknown what the effect of time to clinical evaluation (TTCE) in this association is. We tested the NIHSS scores as an instrument to determine vessel occlusion (VO) at different time points from symptom onset. METHODS: Patients were selected from our prospective stroke database if they had admission NIHSS scores and intracranial vessel neuroimaging studies. We dichotomized patients according to VO and TTCE. Receiver operating curves, c statistics, and odds ratios were calculated to study the validity of the NIHSS score. RESULTS: Among 463 patients (mean age 70.2 years, 53.1% male, median NIHSS 4, median TTCE 3.3 hours), 22.5% had arterial occlusion. Median NIHSS scores were higher in patients with VO, 10.5 (interquartile range 5-18) vs 3 (2-7), p<0.001, and in those with TTCE<6 hours, 15 (interquartile range 7-19) vs 4 (2-8) if ≥6 hours, p<0.001. Receiver operating characteristic curves showed that the validity of NIHSS in predicting VO was higher in patients with TTCE<6 hours, p=0.03. The best cutoff point in patients evaluated before 6 hours was an NIHSS of 7 (76.2% sensitivity, specificity 70.1%), while in patients evaluated after 6 hours the best cutoff point was 4 (sensitivity 65.4%, specificity 62.0%). CONCLUSIONS: Our study shows that the validity of NIHSS scores in predicting arterial occlusion is time-dependent, decreasing with increasing time from symptom onset to clinical evaluation.

[Study on the quality of life in patients with ischaemic stroke]. / Estudio sobre la calidad de vida en pacientes con accidente vascular cerebral isquémico.

AIM: To study the quality of life (QoL) and functional neurological status of patients three years after suffering their first ischaemic cerebrovascular accident (CVA). PATIENTS AND METHODS: For the study we chose patients who presented ischaemic CVA, classified in categories I 63 to I 69. QoL and functional neurological status were measured using the modified Rankin Scale (mRS) and the SF-36 health questionnaire, respectively. RESULTS: Of a total of 59 patients who answered the surveys (mean age: 62 years; sex: 51% females), nearly half of them (29 patients; 49.1%) presented some kind of disability (mRS = 2). Thirty patients (50.9%) were independent or presented minimum sequelae (mRS = 1) at the end of the follow-up period. The mean QoL with the SF-36 questionnaire progressively diminished as the mRS score increased, especially in the group with mRS = 3. Although the youngest age group (range: 20-36 years) got the best average score (84 points) on the SF-36, no significant differences were found with the remaining age groups; the group made up of 75-year-olds and above was the one that obtained the lowest average score (63 points). Extensive strokes (total anterior circulation infarctions) of a cardioembolic origin (atrial fibrillation) had the lowest QoL indexes (p < 0.05). CONCLUSIONS: In the population that was analysed, the QoL was inversely proportional to the age and the severity of the functional deficit of patients who survived a completed stroke, especially in the cardioembolic-origin subgroup, due to its being associated with more extensive cerebral infarcts.

Mortality trends from burn injuries in Chile: 1954-1999.

OBJECTIVES: To study mortality trends due to burns in Chile. METHODS: Correlation, and descriptive study. Death reports from the Annals of Demography from 1954 to 1999, were analyzed and standardized rates of mortality by etiology, age and sex were calculated using regression models (Prais-Winsten) for each of them. Spearman's Rho test was used to show correlations (STATA 7.0). RESULTS: Linear reduction in burns rate (7.03-0.53) was found mainly because of a reduction in the pediatric group (15.3-2.4). The rate in the elder group showed a significant increase (4.28-11.03). The mortality rate due to chemical burns remained stable (1.4/1,000,000) and electrical burns showed an important increase since the 1990s (0.4-5.0/1,000,000). CONCLUSIONS: The decrease of the mortality rates due to burns, is mainly due to a large decrease in the pediatric group rates. Rates remained relatively stable for adults and increased in elders. The findings set a challenge to improve prevention campaigns and professional assessment and management in adults and elders.

[The study of patient survival in cerebral hemorrhagic and ischemic accident]. / Estudio de la supervivencia de los pacientes con accidente vascular encefálico isquémico y hemorrágico.

The aim of this study was to study stroke survival in Chile in a historic cohort from a random sample of 333 inpatients. All alive selected patients were visited and examined. All the death certificates were reviewed. The diagnosis was done by a neurologist, 35% had a CT scan. Survival was measured in days using lifetest procedure to generate survival curves, Cox's proportional hazards models in Stata 3.1 statistic package and logistic regression analysis. The mean age was 70.5 for the group of died and 62.3 years old for alive patients (p = 0.01). Infectious disease (p = 0.05), localization of stroke (p = 0.01) and rehabilitation (p = 0.005) were significant at univariate analysis. The cumulative probability of survival was 38 days, after one year and after five years, 48.1, 39.0 and 19.8%, respectively. The probability of survival by age, localization, heart disease and rehabilitation was statistically significant. Analysis of survival by sex, and previous stroke risk factors was not significant. Using Cox's proportional hazards regression we found that survival after 5 years depends on age (p = 0.03), rehabilitation (p = 0.008), infection (p = 0.05) and heart disease (p = 0.04). Stroke survival function is close to a decreasing exponential curve with high death probability at one month after the stroke. Survival is conditioned by stroke localization, age, heart disease and rehabilitation.