[Genetic and environmental factors that may influence in the senile form of Alzheimer's disease: nested case control studies]. / Factores genéticos y ambientales que pueden influir en la forma senil de la enfermedad de Alzheimer: estudio de casos y controles anidado.

INTRODUCTION: We identify the genetic and environmental factors associated to Alzheimer's disease (AD) in a population aged 80 years or greater. POPULATION STUDIED: subjects who participated in the COGMANLLEU study on prevalence of cognitive deterioration in Manlleu (Osona, Central Catalonia). DESIGN: nested case control studies. The subjects who were diagnosed of AD (cases) in phases 2 of said study were paired 1:1 by age and gender with control subjects who were selected from among those who had no suspicion of cognitive deterioration and who had been examined in phase 1 of the study. The participating subjects (cases and controls) and their family or caregivers were interviewed. This included psychometric tests, physical examination, biological measurements, cranial computed tomography scan and determination of ApoE genotype. RESULTS: Age is the principal factor associated to AD: risk of getting the disease is six time greater among those over 85 years (odds ratio [OR]: 6.54; 95% confidence interval [CI]: 2.05-20.81; p<0.05). Other factors associated of AD were female gender (OR: 3.17; 95 % CI: 0.80-12.50) and having been exposed to general anesthesia (OR: 3.22; 95 % CI: 1.03-10.09; p < 0.05). Arterial hypertension (AHT) presented a negative association (OR: 0.37; 95% CI: 0.10-1.31; p<0.05). An association was also observed between AD and the presence of ApoE4 allele so that the likelihood of ApoE4 in subjects with AD was three times greater than in the control group (OR: 3.44; 95% CI: 0.67-17.62). CONCLUSIONS: The results agree with the hypothesis that senile AD is a complex, multifactorial disease in which different genetic and environmental factors play a part, among which having received general anesthesia has a role that can be considered in future research.

Factores genéticos y ambientales que pueden influir en la forma senil de laenfermedad de Alzheimer: estudiode casos y controles anidado / Genetic and environmental factors that may influence in the senile form of Alzheimer's disease: nested case control studies

Introducción. Se identifican los factores genéticos y ambientalesasociados a la enfermedad de Alzheimer (EA) en una población deedad igual o superior a 80 años.Método. Población estudiada: sujetos que participaron en el estudioCOGMANLLEU sobre prevalencia de deterioro cognitivo en Manlleu(Osona, Cataluña central). Diseño: estudio de casos y controles anidado.Los sujetos que fueron diagnosticados de EA (casos) en la fase 2 delmencionado estudio se emparejaron 1:1 por edad y sexo a sujetos controlque se seleccionaron entre los que no presentaron ninguna sospechade deterioro cognitivo y que habían sido examinados en la fase 1del estudio. Se realizó una entrevista a los sujetos participantes (casosy controles) y a sus familiares o cuidadores que incluyó pruebas psicométricas,exploración física, determinaciones biológicas, tomografíacomputarizada craneal y determinación del genotipo ApoE.Resultados. La edad es el principal factor asociado a la EA: elriesgo de contraer la enfermedad es seis veces superior entre los mayoresde 85 años (odds ratio [OR]: 6,54; intervalo de confianza [IC]95%: 2,05-20,81; p<0,05). Otros factores asociados a la EA fueron elsexo femenino (OR: 3,17; IC 95 %: 0,80-12,50) y haber estado expuestosa anestesia general (OR: 3,22; IC 95%: 1,03-10,09; p<0,05).La hipertensión arterial (HTA) presentaba una asociación negativa(OR: 0,37; IC 95 %: 0,10-1,31; p<0,05). También se observó asociaciónentre la EA y la presencia del alelo ApoE4 de manera que la probabilidadde ApoE4 en los sujetos con EA era tres veces superior a ladel grupo control (OR: 3,44; IC 95%: 0,67-17,62).Conclusiones. Los resultados concuerdan con la hipótesis deque la EA senil es una enfermedad compleja, multifactorial, en la queintervienen diversos factores genéticos y ambientales entre los queel recibir anestesia general puede desempeñar un papel a consideraren investigaciones futuras (AU)

Introduction. We identify the genetic and environmentalfactors associated to Alzheimer's disease (AD) in a populationaged 80 years or greater.Method. Population studied: subjects who participated in theCOGMANLLEU study on prevalence of cognitive deterioration inManlleu (Osona, Central Catalonia). Design: nested case controlstudies. The subjects who were diagnosed of AD (cases) in phases2 of said study were paired 1:1 by age and gender with controlsubjects who were selected from among those who had no suspicionof cognitive deterioration and who had been examined inphase 1 of the study. The participating subjects (cases and controls)and their family or caregivers were interviewed. This includedpsychometric tests, physical examination, biological measurements,cranial computed tomography scan and determinationof ApoE genotype.Results. Age is the principal factor associated to AD: risk ofgetting the disease is six time greater among those over 85 years(odds ratio [OR]: 6.54; 95% confidence in-terval [CI]: 2.05-20.81;p<0.05). Other factors associated of AD were female gender (OR:3.17; 95 % CI: 0.80-12.50) and having been exposed to generalanesthesia (OR: 3.22; 95 % CI: 1.03-10.09; p < 0.05). Arterialhypertension (AHT) presented a negative association (OR: 0.37;95% CI: 0.10-1.31; p<0.05). An association was also observedbetween AD and the presence of ApoE4 allele so that the likelihoodof ApoE4 in subjects with AD was three times greater thanin the control group (OR: 3.44; 95% CI: 0.67-17.62).Conclusions. The results agree with the hypothesis that senileAD is a complex, multifactorial disease in which different geneticand environmental factors play a part, among which havingreceived general anesthesia has a role that can beconsidered in future research (AU)