[Long-term survival related to cognitive performance in older adults treated at a tertiary hospital level]. / Sobrevida a largo plazo relacionada con el desempeño cognoscitivo en adultos mayores atendidos en un hospital de enseñanza de tercer nivel.

OBJECTIVE: To determine the association between cognitive performance and long-term survival in an elderly Mexican population sample. METHODS: In this retrospective, retrolective and observational study elderly subjects were assessed in the Geriatrics Clinic of the Instituto Nacional de Ciencias Médicas y Nutrición "Salvador Zubirán" between January 1994 and August 1999 using a comprehensive geriatric assessment. All 2544 subjects for whom vitality status was known up to September 2002 were included in the analysis. Socio-demographic and health-related information was gathered during the clinical interview, and their emotional and functional status was determined using the Katz, Lawton and GDS scales. Cognition was measured using the Mini-Mental State Examination (MMSE), grouping the subjects according to their performance into four groups: normal-high performance, normal-low performance, mild-to-moderate impairment and moderate-to-severe impairment. Vitality status was determined by searching the hospital's clinical records or by telephonic contact with the patient or primary caregiver when needed. RESULTS: Long-term mortality rates increased in a linear fashion as MMSE scores decreased (p < 0.001), even for MMSE scores over 24. This association persisted even after adjustment for comorbidity, depression, functional status and socio-demographic factors. CONCLUSION: Patients showed a progressive decline in long-term survival according to their cognitive performances. MMSE scores between 24 and 27 were also associated with an increased mortality and should not be considered as normal, even if they are not sensitive enough to detect impairment.

Apolipoprotein E epsilon4, Alzheimer's disease, and cognitive performance in elderly Mexican Mestizos.

OBJECTIVES: To determine the relationship between apolipoprotein E (APOE) epsilon4 and Alzheimer's disease (AD) in the Mexican Mestizo population, as well as its effects on the cognitive profile of AD and elderly Mestizos without dementia. DESIGN: Cross-sectional analysis of a cohort study. SETTING: Evaluations were conducted at the geriatrics clinic of an academic medical hospital in Mexico City. PARTICIPANTS: Forty-nine elderly subjects with AD and 141 controls selected from a representative sample of Mexican Mestizos aged 65 to 96 who participated in the Prevalence Survey of Dementia in the Mexico City Elderly Population cohort. MEASUREMENTS: All subjects underwent APOE genotypification and a comprehensive clinical and neuropsychological evaluation. RESULTS: There were no significant differences in epsilon3 and epsilon4 frequencies between the subjects with and without AD and a tendency toward higher epsilon4 and lower epsilon3 allele frequencies in subjects aged 75 and older. No association was found between APOE epsilon4 and the presence of AD. The age-, sex-, and education-adjusted risk for AD associated with at least one epsilon4 allele was 1.01 (95% confidence interval=0.45-2.23). Performance on a long-term visual memory test was significantly worse in APOE epsilon4 carriers than in APOE epsilon3 carriers only in the group with AD. CONCLUSION: APOE epsilon4 did not increase the risk for AD in this Mexican Mestizo elderly urban population sample, although the presence of this allele seems to modify its clinical expression.

Incidence of delirium, risk factors, and long-term survival of elderly patients hospitalized in a medical specialty teaching hospital in Mexico City.

BACKGROUND: We determined the incidence, probable risk factors, causes, and long-term survival of delirium in patients hospitalized in a medical specialty teaching hospital in Mexico City. METHOD: From June to December 1995, 667 elderly patients 60 years and older were hospitalized and assessed within 48 hours, excluding those with delirium at admission, those sedated, on respiratory support, or unable to speak. RESULTS: Twelve percent of the population developed delirium, identified by means of the daily application of the Confusion Assessment Method; its appearance was attributed in 50% to two or more causes, in 10% to an insufficient control of pain, in 7.5% to a preceding surgical event, and in the rest to other causes. Each case was compared randomly with three nonpaired control patients of the same cohort who did not develop delirium. There was a significant increase in the number of cases of delirium in patients older than 75 years (p < .001), those with low schooling (p = .04), those with greater comorbidity (p < .001), those with a hematocrit lower than 30% (relative risk [RR] 2.1, confidence interval [CI] 1.2-4.1), and those with a glucose level greater than 140 mg/dl (RR 2.1, CI 1.2-3.6). Patients with delirium remained hospitalized longer than controls (p = .02). There was no significant difference in the intrahospital mortality of both groups, although during 5 years' follow-up, survivors demonstrated a significant increase in mortality (p = .03) in the group of individuals with delirium during the hospital stay when compared to controls. CONCLUSION: In this geriatric population of Mexican patients, delirium incidence was similar to that previously reported in the worldwide literature. Its incidence is associated with longer hospital stay and greater mortality. Age, low level of schooling, greater comorbidity, high glucose levels, poor pain control, and hematocrit lower than 30% were independently associated with a greater incidence of delirium.