martes, 31 de agosto de 2010

Efectos a corto plazo por escuchar Reproductores MP3

Estos investigadores Belgas determinaron los niveles de salida en el comercio de la venta de MPEG Layer-3 (MP3) y para evaluar los cambios en la audición después de 1 hora de escuchar el reproductor de MP3 en 21 participantes. En primer lugar, se midieron en decibelios (dBA) los niveles de presión sonora ponderada-A, durante 1 hora de música pop-rock en un reproductor de MP3 se midieron en un simulador de cabeza y torso. En segundo lugar, después que los participantes escucharon a 1 hora de música pop-rock con un reproductor de MP3, los cambios en la audición fueron evaluados con audiometría de tonos puros, las emisiones otoacústicas evocadas transitorias, y las emisiones otoacústicas por productos de distorsión
Ellos encontraron: "Los niveles de salida en el ajuste de ganancia total fueron 97,36 dBA y 102,56 dBA para los auriculares supra-aurales y auriculares de acciones, respectivamente. En el grupo de exposición al ruido, los cambios significativos en los umbrales de audición y amplitudes de las emisiones otoacústicas evocadas transitorias se encontraron entre las mediciones de preexposición y postexposición. Sin embargo, este patrón no se observó para amplitudes de las emisiones otoacústicas por productos de distorsión. Diferencias significativas en la incidencia de los cambios de umbral significativos o de emisiones se observaron entre casi todas las sesiones del grupo de la exposición al ruido en comparación con el grupo de control".
Los autores concluyeron: "Cambios temporales en la sensibilidad auditiva medida por audiometría y las emisiones otoacústicas indican los posibles efectos nocivos de escuchar un reproductor MP3. Se requieren más estudios para evaluar el riesgo a largo plazo de la exposición acumulativa al ruido sobre el sistema auditivo de los adolescentes y los adultos".

Fuente: Arch Otolaryngol Head Neck Surg 136(6):538-548, June 2010

How Much Activity is Required to Prevent Weight Gain?

Study Question: In 2008, federal guidelines recommended at least 150 minutes per week (7.5 metabolic equivalent [MET] hours per week) of moderate-intensity activity for “substantial health benefits.” What is the association of physical activity with long-term weight changes among women consuming a usual diet?

Methods: This prospective cohort study involved 34,079 healthy women participating in the Women’s Health Study from 1992-2007. At baseline and years 3, 6, 8, 10, 12, and 13, women reported their physical activity and body weight. Women were classified as expending <7.5,>Results: At baseline, mean age was 54.2 years; about 50% of the women expended <7.5 p =" 0.003)" p =" 0.002)." trend =" 0.56)" trend =" 0.50)." color="#000099">Conclusions: Among women consuming a usual diet, physical activity was associated with less weight gain only among women whose BMI was lower than 25 kg/m2. Women successful in maintaining normal weight and gaining fewer than 2.3 kg over 13 years averaged approximately 60 minutes a day of moderate-intensity activity throughout the study.

Perspective: How many women 52 years of age would exercise 60 minutes a day in order to not gain more than 5 pounds over 13 years? One per 1,000? The authors had two posits, neither of which makes sense: 1) once overweight, it may be too late because physical activity is not associated with less weight gain; 2) sustaining high levels of physical activity (~60 minutes a day) is needed to successfully maintain normal BMI and prevent weight gain. While MET hours per week of activity is a reasonable way to estimate kcal/day of energy expenditure, over 95% of kcal of energy is expended at rest or during sleep. Weight gain in middle-aged men and women is highly related to increasing energy intake, which was not measured in these women. Adding the equivalent of one slice of bread per day (100 kcal) could on average result in ~10 pounds of weight gain in 1 year. The impact of supersizing and fast foods cannot be overcome by exercise.

Fuente: JAMA 2010;303:1173-1179

viernes, 27 de agosto de 2010

Causas de mareos en los ancianos

El mareo es una queja común en los entornos de atención primaria que tiene muchas posibles etiologías. Estos investigadores neerlandeses y británicos trataron de caracterizar los subtipos de mareos en pacientes geriátricos en atención primaria y para evaluar sus causas. Se realizó un estudio transversal de diagnóstico en los pacientes geriátricos en los Países Bajos vistos por mareo persistente por sus médicos de familia. Un panel conformado por un médico de familia, un geriatra, y de enfermera en casa, quien revisó las evaluaciones integrales de cada paciente que se les realizaron para determinar las causas contributivas de mareo.
Los investigadores reportaron: "Desde junio 2006 hasta enero 2008, se incluyeron 417 pacientes de 65 a 95 años. El presíncope fue el subtipo más común de mareos (69%). Al cuarenta y cuatro por ciento de los pacientes les fue asignado más de un subtipo mareos. La Enfermedad Cardiovascular fue considerada como la causa contributiva más común de mareo (57%), seguidos de la enfermedad vestibular periférica (14%) y las enfermedades psiquiátricas (10%). Un efecto adverso fue considerado como la causa contributiva más común de mareos menores (23%). Al sesenta y dos por ciento de los pacientes les fue asignada más de 1 causa contributiva de mareo.
Los investigadores concluyeron: "Contrariamente a la mayoría de los estudios previos, la enfermedad cardiovascular se encontró que la principal causa más común de mareo en pacientes ancianos en atención primaria. En la cuarta parte de todos los pacientes un efecto adverso fue considerado como una causa que contribuye al mareo, el cual es mucho más alto que lo reportado en estudios anteriores. "
Fuente: Annals of Family Medicine 8(3):196-205, May/June 2010

Allopurinol use associated with better heart failure outcomes

Hyperuricemia is associated with reduced survival among patients with heart failure (HF), but the effect of gout on HF outcomes is unknown. The objective of this study by Canadian authors was to determine whether gout and allopurinol use are associated with HF outcomes. They performed a time-matched, nested case-control analysis of a retrospective cohort of patients with HF who were 66 years or older using health care databases in Quebec, Canada. The primary outcome measure was a composite measure of HF readmission and all-cause mortality. The secondary outcome measure was all-cause mortality.
They found: "Of the 25,090 patients in this cohort, 14,327 experienced the primary outcome. Both a remote history of gout and an acute episode of gout (within 60 days of the event date) were associated with an increased risk of HF readmission or death (adjusted rate ratio 1.63 and 2.06, respectively). Continuous allopurinol use (greater than 30 days of continuous use) was not associated with the primary outcome among the overall population with HF, but was associated with reduced HF readmissions or death (0.69) and all-cause mortality (0.74) among patients with a history of gout."The authors concluded: "Patients with HF and a history of gout represent a high-risk population. Among such patients, the use of allopurinol is associated with improved outcomes."
Arch Intern Med 170(15):1358-1364, 9/23 August 2010 © 2010 to the American Medical AssociationGout, Allopurinol Use, and Heart Failure Outcomes. George Thanassoulis, James M. Brophy, Hugues Richard, Louise Pilote.

lunes, 23 de agosto de 2010

De lo mejorcito que me han enviado...


LE FALTÓ AL LETRERITO QUE DIGA:
SU DROGA ES DE COLOMBIA,
SU PETROLEO ES DE MÉXICO Y
SU IDIOMA ES DE INGLATERRA.
AAAHH Y SU PRESIDENTE ES DE ÁFRICA.
ENTONCES, ESTOS QUE CREEN QUE APORTAN AL MUNDO?

Limited evidence on most effective prophylaxis for chloroquine-resistant malaria

Clinical Question: What is the most effective and safest prophylactic anti-malarial for non-immune adults and children travelling to regions with Plasmodium falciparum resistance to
Bottom line: Atovaquone-proguanil and doxycycline were well tolerated by most travellers, and they were less likely than mefloquine to cause neuropsychiatric adverse events. Chloroquine-proguanil caused more gastrointestinal adverse events than other chemoprophylaxis. In other respects, the common unwanted effects of currently available drugs were similar. There was no evidence from head-to-head comparisons to support primaquine use as primary prophylaxis for travellers. The choice of whether to prescribe atovaquoneproguanil or doxycycline (or exceptionally, mefloquine) should be made by health practitioners by taking into account additional factors such as cost, known contraindications to any of the drugs in question (eg, pregnancy, breastfeeding, age), known rare serious adverse events, previous use of the drugs, possible drug-drug interactions, ease of administration, travel itinerary and the additional protection that may be afforded by doxycycline against other infections, besides malaria.
Caveat: The body of evidence was small, and the quality of evidence ranged from very low to moderate. Except for 2 trials, all the studies in this review were funded wholly or in part by pharmaceutical companies. As well as the 8 trials, there were also 22 published case reports of deaths, including five suicides, associated with mefloquine use at normal dosages. No other currently used drugs were reported as causing death at normal dosages.
Context: Malaria infects 10,000 to 30,000 international travellers each year. It can be prevented through anti-mosquito measures and drug prophylaxis. However, anti-malarial drugs have adverse effects which are sometimes serious.
Cochrane Systematic Review: Jacquerioz FA and Croft AM. Drugs for preventing malaria in travellers. Cochrane Reviews 2009, Issue 4. Article No. CD006491. DOI: 10.1002/14651858.CD006491.pub2. This review contains 8 studies involving 4240 participants

Insulin pumps for management of type 1 diabetes

Recently developed technologies for the treatment of type 1 diabetes mellitus include a variety of pumps and pumps with glucose sensors. In this 1-year, multicenter, randomized, controlled trial, the US authors compared the efficacy of sensor-augmented pump therapy (pump therapy) with that of a regimen of multiple daily insulin injections (injection therapy) in 485 patients (329 adults and 156 children) with inadequately controlled type 1 diabetes.
Patients received recombinant insulin analogues and were supervised by expert clinical teams.They found: "At 1 year, the baseline mean glycated hemoglobin level (8.3% in the two study groups) had decreased to 7.5% in the pump-therapy group, as compared with 8.1% in the injection-therapy group.
The proportion of patients who reached the glycated hemoglobin target (les than 7%) was greater in the pump-therapy group than in the injection-therapy group. The rate of severe hypoglycemia in the pump-therapy group (13.31 cases per 100 person- years) did not differ significantly from that in the injection-therapy group (13.48 per 100 person-years). There was no significant weight gain in either group.
"The authors concluded: "In both adults and children with inadequately controlled type 1 diabetes, sensor-augmented pump therapy resulted in significant improvement in glycated hemoglobin levels, as compared with injection therapy. A significantly greater proportion of both adults and children in the pump-therapy group than in the injection-therapy group reached the target glycated hemoglobin level."

Original: N Engl J Med 363(4):311-320, 22 July 2010

lunes, 9 de agosto de 2010

Le sucedió a éste médico...

Un médico se encontraba sentado en la silla de su consultorio, después de tener sexo con su paciente.

Pensando en lo que había hecho, su conciencia le repetía: 'pero cómo hice eso' qué verguenza, perdí toda la ética profesional! !!! 'Dios míoooooo..... que hago?'

Al rato de estar culpándose de sus actos, observa que sobre su hombro derecho aparece un diablito que le dice: 'Escuchame.. . no seas baboso...
¡hay una cantidad exagerada de médicos que tienen sexo con sus pacientes! ¿qué te crees? ¿que eres el único que lo ha hecho? Hazme caso.... es de lo más natural del mundo.... quedate tranquilo, al fin lo disfrutaste!!!

El médico convencido, dice: 'Tienes razón, si yo no hice nada malo, simplemente me deje llevar por el placer'.

Al terminar de decir eso, en su otro hombro aparece un angelito y le le replica al oído:
'Yo nada mas te digo: Acuerdate que eres veterinario! !! VE-TE-RI-NA- RIO....!!!

jueves, 5 de agosto de 2010

Que orgullo para mi país el triple medallista de oro (Juegos CA y el del Caribe, Mayagüez, Puerto Rico, 2010) en bádminton Kevin Cordón.
Felicitaciones Ecuador por NO permitir la explotación petrolera en su Amazonía.