Estatinas en adultos mayores, una población creciente / Statins used in the elderly, a growing population

El riesgo cardiovascular es responsable de un cuarto de las muertes por enfermedad coronaria, y dentro de estos pacientes el 75% son mayores de 65 años de edad, población a la que nos enfocaremos en esta revisión. Por ello es de suma importancia considerar tanto los beneficios clínicos como económicos de una terapia preventiva en este grupo poblacional. La prescripción en los ancianos se ha convertido en la actualidad en una cuestión compleja que tiende a incrementar el uso irracional de los fármacos, los errores de medicación, los efectos adversos, así como la subutilización o sobreutilización de los mismos. Las estatinas (inhibidores de la HMG-CoA reductasa), son consideradas como el tratamiento hipolipemiante de primera elección para la disminución del riesgo cardiovascular y a pesar de no haber publicaciones enfocadas en el uso exclusivo de estatinas en la población de adultos mayores así como de múltiples controversias, se pueden encontrar beneficios similares a los percibidos en poblaciones más jóvenes, pero con un enfoque en prevención primaria en la población de edad avanzada.

The cardiovascular risk is responsible for a quarter splits of deaths by coronary illness and inside these patients, three quarter splits are greater than 65 years old. Because of it, it's very important to consider the clinical and economic benefits of a preventive therapy in this population group. The statins (inhibiting of the HMG-CoA reductasa), are considered as the greater hypolipemic therapy election for decrease the cardiovascular risk and in spite of not there to be publications focused in the exclusive use of statins in the population of older adults, besides multiple controversies, similar benefits to them can be found perceived in younger populations, but with a focus in primary prevention in the population of advanced age.

La neurocirugía en los trastornos de la alimentación: ¿una alternativa posible?

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Abstract: Composition and quantity of food in-taken varies considerably between one meal and another, or between one day and the following. Non biological factors -such as emotional, social, day time, feasibility in the type of food, and cost- are, among others, factors that in some way affect the degree of energy in-take by food, which generally is not related with daily energy expenditure. These phenomena represent an active process of regulation that is characterized by the balance between signs that stimulate hunger, called orexigenics and those that produce satiation to stop in-take, called anorexigenics, that promotes the stability in the quantity of corporal energy manifested as fat. In this feeding regulatory process there are many molecular signs that participate and regulate the in-take of behaviour food for homeostasis. There are two hypothalamic centers related with the food in-take control: the hunger centre in the lateral hypothalamus and the satiation centre in the ventromedial nucleus. In this control many impulses participate, regulated by substances called neurotransmitters, such as: neuropeptide Y, galanine, orexines for the hunger centre and nor epinephrine, serotonin, and dopamine for the satiation centre. Insulin reaches the brain through circulation and acts reducing the contribution of energy, it was the first hormonal sign that was implicated in weight control by CNS. The second identified hormone, secreted by the adiposity, was leptin. Both hormones circulate in levels proportional to the corporal fat and get to the CNS in proportion to its plasmatic concentrations. Receptors as leptin and insulin are expressed by brain neurons involved in the contribution of energy, and the administration of any of both peptides directly to the brain, reduce the in-take of food. The lack of any of these hormones produces the opposite. Leptin has a more important role than insulin in the control of the energetic homeostasis in the CNS. For example, the lack of leptin causes severe obesity with hyperfagia that persists regardless the levels of elevated insulin. In contrast, obesity isn't induced by the lack of insulin. Insulin has a critic role to promote the storage of fat and the synthesis of leptin through the fat cellule. The neuropeptide Y, produced in the arcuate nucleus of the hypothalamus has an anabolic effect. The gene of expression and secretion of this peptide in the hypothalamus increases during depletion, in the storage of corporal fat and/or when the signs of leptin/insulin are decreased in the brain. Leptin inhibits the gene of expression of the neuropeptide Y in the arcuate nucleus and the genetic "knockout" of the NPY reduces hyperfagia and obesity in mice ob/ob, indicating that the total response to the lack of leptin requires the signs of the NPY. Other substances like the Agouti protein (AGRP), the orexines (hypocretines A and B) and the concentrations of the melancortin hormone have been added to the molecule candidate list with anabolic effects. Also in the adjoining neurons of the arcuate nucleus, are originated anorexigenic peptides like alfa-MSH (a derivated of the pro-opiomelancortin, POMC) and CART (transcript protein related with cocaine and amphetamine). Both types of neurons (NPY/AGRP and POMC/CART) coexpress the leptin receptors. In those situations in which the levels of leptin or insulin are low, the NPY/AGRP neurons activate and the POMC/CART are inhibited. This suggests that the main site of adiposity signs transformation is a neuronal response in the arched nucleus. The link between the lateral hypothalamus and the elevated centers of the brain that regulate hunger and satiation is a very important aspect of the regulation system. There have been typified two types of neuropeptides linked to neurons, that appear to be exclusively of the lateral hypothalamus area: the concentrated melanin hormone (MCH) and the orexines. At the lateral zone, there have been specified two types of hypothalamic neuropeptides, the orexines A and B, also known as hypocretines 1 and 2, which are cellular bodies of the hypothalamus, especially at the lateral hypothalamus and the perifornical area, which stimulate the appetite in an independent way to other neuropeptides known. On the other hand, the orexines A and B derive (by proteolysis) of a common precursor, and are capable of activating their two respective receptors that work in conjunction with proteins G. The central administration of orexines stimulates the in-take and production of orexines' increase with fasting. These neuropeptides match with the hypocretines described by other authors, with expression in late ral hypothalamus, arched nucleus, septal nucleus and forebrain. Monoaminergic neurotransmitters. Noradrenalin Noradrenalin is synthesized in different areas of the brain such as the dorsal nucleus of the vague and the locus coeruleus.Noradrenalin shares the same place with NPY and the injection of both inside the preventricular nucleus increase the in-take of food. The repeated injection can result in weight increase; leptin can inhibit noradrenalin secretion. Dopamine Critic dependence of the in-take of food in the CNS is given by the dopamine sign, which is implicated in the voluntary lack of the food in-take. Motor alterations associated with the lack of dopamine affect also the alimentary behavior. The dopamine effect over the alimentary behavior varies depending of the studyied area. For example the routes of dopamine in the mesolimbic area contribute to the reward of the in-take of savory food. SerotoninThe 5HT2c receptor of serotonin is implicated in the decrease of the in-take of food and the weight increase, due to its effect in the impulse of the satiation centre. To maintain the homeostasis of normal energy it is necessary that the serotonin sign be intact. New alternative hypothesis. On one hand, the knowledge of regulation of the appetite-satiety neuroendocrine cycle, and on the other, the new techniques of neuromodulation through stereotaxic surgery, allow to offer an extraordinarily interesting field of research in certain patients with feeding disorders of difficult control and with an increase in the mortality risk. The alternative of controlling specific centers of hunger/satiation regulation, is still a hypothesis, though there are some data that allow us to assume that it could be feasible and we will mention them after. Current experience. Stereotaxic (Latin: stereo, three-dimensional; taxis, positioning) is a modern technique of neurosurgery that allows the localization and precise access to intra-cerebral structures, through a small orifice in the skull. If we have identified the places that regulate the intake of food or satiety, it is feasible that through this technique we can stimulate or inhibit this function and offer the patient an alternative that in theory could be feasible. Some of its possible advantages will be that we are talking about a minimum invasive surgery, generally performed using local anesthesia; patients need a minimum hospitalization stay and surgical risks are minimized. This allows us to predict in the majority of the patients a satisfactory evolution of weight decrease. The current experience of stereotaxic used in eating disorders is null; everything about it is hypothetic. However, the use of this proceeding for other accepted indications where there is previous experience, has allowed us to obtain interesting data of the evolution of these patients that shows indirectly, that the procedure has influenced in the corporal weight. We present these indirect results, which motivate us to continue considering its possible use in patients that show the approved profile according to an ethic committee properly authorized. In depression or bipolar disorder cases, the use of the stereotaxic surgery applying electrodes in the bottom pedunculo thalamic region (ITP), independently that they show an improve in their basal alteration, the patients show a weight increase, inferring a relationship of this area and the one of the hypothalamus for the appetite/satiation control, situation that hypothetically could benefit patients with anorexia nervosa or bulimia. In the cases with Parkinson Disease, the stereotaxic procedure has been made in the pre-lemniscal (RAPRL) or the subtalamic region (STN) in a unilateral or bilateral way, and although the response hasn't been uniform, the weight changes showed a decrease, making this a possible alternative to be used in some patients with morbid obesity according to the inclusion criteria. Final comments. The expectative of stereotaxic surgery in handling patients with difficult to control feeding disorders or with high risk of morbid-mortality, is shown as an hypothesis, that should consider the specific rules of good clinical practices and adjust to the rules of an approved ethics committee, for these procedures.

Comparative accuracy of glucose monitors

Background. Self-monitoring of blood glucose levels has become an important instrument for the management of patients with diabetes mellitus. Both patients and physicians expect that monitors will provide reliable results. Numerous environmental, physiologic, and operational factors can affects system performance, yielding results that are inaccurate or unpredictable. Methods. This study examined the effect of one factor -high altitude- on the performance of seven blood glucose monitoring systems. The following monitors were compared. two One Touch II; two One Touch Basic; two Reflolux II (Accu-Chec in the USA); two Glucometer 3; one Glucometer 2, and one Accutrend Alpha. Double blood glucose level values were compared with a cotrolled reference laboratory test values, which was unknown to the investigator until the end of the study because the study was double blind. Blood glucose values were obtained using each of the monitors in 200 patients; 150 with diabetes mellitus, and 50 healthy subjects. Results. The One Touch monitors were the only monitors that reported adjusted straight lines (Y0a+bX) that were very similar for all three techniques. In addition, these adjusted straight lines are those closest to the ideal line, Y=X. These same monitors were the only ones that did not reject the null hypothesis Ho: a=0. The relative deviation index at the 20 percent level was less than 3.5 percent for the One Touch II and One Touch Basic monitors; for the rest of the monitors the index was over 14 percent. The clinically accepted EGA region was similar for all study monitors. Conclusions. In conclusion, the One Touch II and One touch Basic Monitors showed greater accuracy in comparison to the other devices. The evaluation of the clinically acceptable region shows practical reliability for all of the monitor used

Effects of metformin on fibrinogen levels in obese patients with type 2 diabetes

Objetivo. Determinar los niveles de fibrinógeno en obesos con diabetes tipo 2 y valorar las potenciales modificaciones que induce la metformina. Métodos. Fue un estudio abierto, prospectivo, randomizado y comparativo que incluyó a 60 pacientes con diabetes tipo 2 obesos (IMC > 27) durante dos fases. La fase de pretratamiento fue de 4 semanas con un control con dieta. En la fase de tratamiento se les dividió en dos subgrupos de 30. Uno recibió una tableta de metformina de 850 mg, incrementándose la dosis a dos o tres tabletas de acuerdo al control metabólico; el otro subgrupo recibió insulina DNA-recombinante 24 U, subcutánea (dos tercios antes del desayuno y un tercio antes de la cena), ajustando la dosis de acuerdo a la respuesta. Como grupo control se incluyeron a 60 sujetos obesos no diabéticos, que durante las dos fases sólo recibieron dieta. Resultados. Los valores promedio de glucosa, fibriógeno y del índice de masa corporal (IMC) no cambiaron en la fase de pretratamiento de controles y diabéticos ni en la fase de tratamiento de los controles. En cambio los tres parámetros disminuyeron significativamente en el subgrupo de metformina (p < 0.001) y soló el de glucosa (p< 0.001) en el subgrupo de insulina. Conclusiones. La metformina, además de mejorar el control metabólico, demostró ser una buena alternativa para modificar favorablemente los niveles de fibrinógeno en pacientes con diabetes tipo 2

Prevalencia de factores de riesgo de enfermedad coronaria en trabadores del Hospital General de México / Prevalence of risk factors of coronary disease in personnel of the Generla Hospital of Mexico

Objetivo. Conocer la prevalencia de algunos factores de riesgo coronario en trabajadores de una institución de salud. Material y métodos. De 1993 a 1995 se evaluaron 2228 trabajadores del Hospital General de México, 1531 mujeres (68.7 por ciento) y 697 hombres (31.2 por ciento) con edades entre 16 a 65 años, y se les clasificó por áreas de trabajo: en Intendencia hubo 477 participaciones (21.4 por ciento); en Administración, 697 (31.2 por ciento); en Personal Médico, 495 (22.2 por ciento), y en Enfermería, 559 (25.0 por ciento). Se les practicó historia clínica, mediciones antropométricas y determinación de glucosa, colesterol total, LDL, HDL y triglicéridos. Resultados. Trescientos sesenta y siete sujetos (14.9 por ciento) tenían colesterol por arriba de 240 mg/dl, con valores altos en las mujeres del área administrativa (17.1 por ciento) y en los hombres del departamento de enfermería (26 por ciento) que presentó la mayor tendencia (26 por ciento). Se encontraron niveles de triglicéridos por arriba de los 200 mg/dl en 471 personas (19.1 por ciento); obesidad, en 329 (13.5 por ciento); hipertensión arterial, en 549 sujetos (22.2 por ciento), y tabaquismo positivo, en 32 por ciento de los trabajadores. La prevalencia de diabetes mellitus fue de 6.24 por ciento. Conclusiones. Se confirma la elevada prevalencia de factores de riesgo de enfermedad cardiovascular entre los trabajadores del Hospital General de México, factores que en muchos casos son modificables, lo que confiere la posibilidad de realizar acciones preventivas

Objective. To evaluate the prevalence of risk factors of coronary heart disease in the personnel of the General Hospital in Mexico City. Material and methods. We studied 2 228 workers, 1 531 female (68.7%) and 697 male (31 .2%) whose ages ranged from 16 to 65 years old in the period of 1993 to 1995. They were divided in work areas: Intendancy 477 (21.4%), Administrative, 697 (31.2%), Physicians, 495 (22.2%) and Nurses, 559 (25.0%). We collected clinical histories, anthropom etric measures, and laboratory determinations of glucose, total cholesterol, LDL, HDL and triglicerydes. Results. We found that 367 (14.9%) had total cholesterol above 240 mg/dl, with high values in females of the administrative area (17.1%) and males in the nursing department (26%), which was the highest tendency. Trigliceryde levels above 200 mg/dl were found in 208 males (24.6%) and 263 females (16.2%), with high prevalence in the nursing and administrative departments, in males (39.1 and 34.1% respectively). Obesity was present in 236 females (14.5%) and 97 males (11.5%). High blood pressure in 549 individuals (22.2%), 297 females (18.3%) and 252 males (29.8%) without significance regarding to work area. Smoking habits were positive in 32% of the total with highest prevalence in males from 30 to 45 years and in females from 30 to 50 years. We found an incidence of 6.24% of diabetes in all the subjects studied, 2.27% ignored the diagnosis at the moment they were studied. Conclusions. In t his study we confirmed the high prevalence of risk factors of coronary heart disease in personnel of the General Hospital in Mexico City. In most cases, these risk factors that can be modified and, therefore, prevented.

Eficacia, seguridad y tolerabilidad de la fluvastatina sódica 40 mg en pacientes con hiperlipidemia tipo IIA / The use of 40 mg of fluvastatin sodium in patients with type IIA hyperlipidemia

La fluvastatina sódica es el primer inhibidor sintético de la reductasa de 3-hidroxi-3mentilglutaril coenzima A. Actúa inhibiendo en forma reversible la síntesis de colesterol y aumentando la catálisis de colesterol de las lipoproteínas de baja densidad y la expresión de receptores LDL en hepatocitos. Para evaluar la eficacia, tolerabilidad y seguridad de la fluvastatina sódica, 40 mg una vez al día, se estudiaron 40 pacientes con dislipidemia tipo IIA. Se observó una disminución significativa en colesterol total: 20.7 por ciento (p<0.01), en colesterol de las lipoproteínas de baja densidad: 29.5 por ciento (p<0.01), en triglicéridos: 10.53 por ciento (p N.S.), en colesterol de las lipoproteínas de muy baja densidad: 10.53 por ciento (p N.S.) y en C-CLDL:C-HDL: 33.7 por ciento (p<0.01). Asimismo, se obtuvo un aumento del colesterol de las lipoproteínas de alta densidad de 2.8 por ciento, después de 12 semanas de tratamiento. No se reportaron efectos secundarios y los exámenes de laboratorio de seguridad no tuvieron ningún cambio. Se concluye, que la fluvastatina sódica 40 mg, una vez al día, es eficaz, bien tolerada y segura en el tratamiento de dislipidemia tipo IIA

Efectos del acipimox sobre el metabolismo de la glucosa y de los lípidos, en pacientes con diabetes mellitus tipo II, obesos de difícil control con hiperlipoproteinemia tipo IIb y IV: resultados de un estudio multicéntrico / Acipimox affects in glucose metabolism in patients with diabetes mellitus type II and hyperlipidemia type IIb or IV

La interacción metabólica entre hidratos de carbono y lípidos, ha permitido considerar la hipótesis de que la corrección con hiperlipidemia en el diabético mal controlado, permite al paciente mejorar su control glucémico, posiblemente modificando la resistencia a la insulina. El objetivo de este trabajo multicéntrico fue evaluar la acción de un hipolipemiante, un análogo del ácido nicotínico acipimox en pacientes diabéticos no insulino dependientes con hiperlipoproteinemia tipo IIb y IV, que presentaban un descontrol metabólico aún recibiendo hipoglucemiantes orales a dosis máximas. La investigación incluyó 133 pacientes, de los que 67 tomaron acipimox por un periodo de tres meses (olbetam, *marca registrada) en dosis de 250 mg tres veces por vía oral; y 66 pacientes (grupo control) a quienes se les administró placebo. Se examinaron diversos parámetros bioquímicos antes de la administración del medicamento, a las cuatro, ocho y 12 semanas. En el grupo con acipimox se observó una disminución estadísticamente significativa de los niveles plasmáticos de triglicéridos, colesterol total, colesterol LDL, glucosa en ayuno y postprandial, hemoglobina glucosilada y un incremento de colesterol HDL. Estos resultados indican que el acipimox es un agente hipolipidemico con efecto sobre el control metabólico, tanto de los lípidos como de la glucosa, en pacientes diabéticos tipo II con hiperlipidemia tipo IIb o IV de difícil control