Continuo ascenso de la prevalencia de diabetes mellitus en mujeres chilenas en edad fértil: proyección 2020-2039 de malformaciones congénitas por diabetes pregestacional

Background: In Chile, in the next 20 years there will be an average number of 537,100 women of childbearing age with type 2 diabetes (T2DM). Half of these women, not knowing their diagnosis of diabetes will become pregnant with elevated glycosylated hemoglobin levels, increasing to 25% the risk of having offspring with congenital malformations. Aim: To calculate the cost-effectiveness of a diabetes detection strategy in women of childbearing age for the prevention of congenital malformations in the period 2020-2039. Material and Methods: The Markov stochastic model was used in two scenarios, namely A: No intervention and B: Intervention, detecting T2DM in Chilean women aged 15-49 years. We calculated the years of life lost due to premature death (YLL), years of life lost adjusted for disability (DALY) and total costs using American dollars (US$) of 2017, with a discount rate of 5%. Results: In scenario A: 63,330 children with malformations would be born, YLLs and DALYs would be 800,750 and 1,544,775 respectively, and US$ 10,194,298,011 would be expended. In scenario B, these figures would be reduced in approximately 70% to 19,025 children born with malformations, YLLS and DALYs would be 40,539 and 464,033 respectively and US$ 3,354,321,968 would be expended. The costs of prevention would be US$ 6,590.94/malformation avoided, US$ 521.33/YLL avoided, and US$ 270.24/DALY avoided. Conclusions: In the context of an increasing prevalence of diabetes in women of childbearing age, our results suggest that the early detection of diabetes in Chilean women between 15 and 49 years of age, should be cost-effective to avoid an increase in congenital malformations for the next 20 years.

Adaptación a un esquema de entrenamiento físico en pacientes con enfermedad pulmonar obstructiva crónica avanzada / Adaptation to a physical training protocol of severe chronic obstructive pulmonary disease patients

El ejercicio físico es un elemento básico en la rehabilitación en pacientes con EPOC. Sin embargo, los resultados son variables, lo que puede deberse a las diferentes estrategias de entrenamiento utilizadas. En 22 pacientes con EPOC avanzada (VEF, 35,6 ñ 15,7 por ciento: edad 63 ñ 15 años; x ñ DS) Evaluamos su adaptación a un esquema de entrenamiento (E) en bicicleta ergométrica que consistió en aplicar inicialmente una carga inicial de 30 por ciento de la máxima previamente determinada (CM) y aumentarla en 15 a 20 por ciento en las sesiones siguientes cuando el paciente era capaz de mantenerla por 45 minutos, hasta alcanzar la meta de 75 por ciento de la CM. La intensidad del E se midió en watts calculando el área bajo la curva de la relación entre las cargas aplicadas y el número de sesiones de entrenamiento. El efecto del E se evaluó a través de los cambios en la carga y el VO2 máximos, la duración de un ejercicio submáximo, la frecuencia cardíaca, (FC), disnea, fatiga de las extremidades inferiores y lactato sanguíneo para una misma carga y tiempo de ejercicio. La CM de E fue 61 ñ 23 por ciento (x ñ DS) del máximo. Seis pacientes no fueron capaces de alcanzar la carga establecida como meta. En los restantes ésta se alcanzó en un número variable de sesiones (12 ñ 7). La intensidad del entrenamiento fue de 952 ñ 325 watt. El E produjo un aumento de la CM (p<0,02) y del tiempo de ejercicio (p<0,0001) y una disminución significativa de la FC, disnea, fatigabilidad y lactato sanguíneo. La duración del ejercicio se correlacionó con la reducción de la disnea (r= -0,448; p<0,05) y la intensidad del entrenamiento con la disminución de la fatiga (r= -0,5176; p = 0,014) y también del lactato sanguíneo (r= -0,488; p = 0,021). Los resultados demuestran que aún cuando la adaptación al esquema de entrenamiento fue variable de acuerdo a la capacidad individual y no pudo ser aplicada a todos los pacientes, la mayoría de ellos obtuvo efectos beneficiosos

Calidad de vida en pacientes con enfermedad pulmonar obstructiva crónica e impacto del entrenamiento físico / Quality of life in patients with chronic pulmonary obstructive disease and the impact of physical training

Background: Health related quality of life (QoL) is severely impaired in COPD patients as a consequence of dyspnea and limited exercise tolerance, which lead to physical deconditioning and muscle atrophy resulting in weakness and fatigue. Psychosocial factors such as depression and anxiety also contribute to this impairment. Aim: To evaluate: a) the impact of COPD on quality of life, and b) the effect of 10 weeks of exercise training on exercise performance and on QoL. Patients and methods: The Spanish version of the Chronic Respiratory Questionnaire (CRQ) was applied to 55 COPD patients (FEV1 37 ñ 13 percent pred) for the assessment of QoL and in 30 of them submitted to exercise training for 10 weeks. Exercise performance was evaluated by measuring: six-minute walking distance, maximal workload (Wmax), maximal O2 consumption (VO2max) as well as endurance time, blood lactic acid, dyspnea and leg fatigue during a submaximal exercise. Trained patients were evaluated before and after training. Results : COPD patients showed a reduction (mean ñ SD) in the four domains of the CRQ: dyspnea (3.1 ñ 0.9); fatigue (4.3 ñ 1.3); mastery (4.65 ñ 1.3), emotional function (4.1 ñ 0.97), and in Wmax and VO2max (52 ñ 16 Watt and 970 ñ 301 ml/min). No significant relationship between the impairment in exercise tolerance and in QoL was observed. Exercise training significantly improved the four domains of QoL (p < 0.0001), Wmax (p < 0.05), VO2max (p < 0.02) and endurance time (p < 0.001). Isotime exercise measurements of dyspnea, leg fatigue and lactic acid decreased after training (p < 0.001, each). No significant relation between changes in QoL and changes in exercise performance were observed. Conclusions: Our results demonstrate that QoL is seriously impaired in patients with COPD and confirm: (a) the lack of relationship of QoL to the usually measured physiological parameters, and (b) the beneficial effect of exercise training on QoL through the reduction of symptoms. These findings stresses the need of measuring quality of life in our patients if we want to evaluate the impact of therapeutic procedures on well-being from the patients' perspective

Potencia de los músculos inspiratorios en insuficiencia cardíaca crónica y en enfermedad pulmonar obstructiva crónica / Respiratory muscle power output in patients with chronic heart failure and patients with chronic pulmonary obstructive disease

Background: The maximal pressure generated by inspiratory muscles (PIMax) is an index of their strength which is diminished in both chronic obstructive pulmonary disease (COPD) and chronic heart failure (CHF). Although inspiratory muscle power output (IMPO), which includes both strength and velocity of shortening, has been shown to be reduced in COPD, there is no information regarding IMPO in CHF. Aim: To measure Impo in patients with CHF and COPD. Patients and methods: We studied 9 CHF patients with functional capacity II and III and 9 patients with severe COPD. Eight normal subjects of similar ages were included as controls. Power output was measured using the incremental threshold loading test. Results: Maximal IMPO was significantly reduced in both groups of patients. Power output developed with each increasing load was also diminished, basically as a consequence of a reduction in insp. The degree of dyspnea at the end of the test was greater in COPD than in CHF patients and normal subjects. For a given level of power, dyspnea was also greater in patients than in normals subjects. There was no decrease in SpO2 during the test. Conclusions: IMPO is equally reduced in COPD and CHF patients. Power output is better related to dyspnea than PIMax, probably because of the inclusion of shortening velocity

Efecto del entrenamiento muscular inspiratorio en el costo de oxígeno de la ventilación en pacientes con enfermedad pulmonar obstructiva crónica / Effects of inspiratory muscle training on the oxygen cost of breathing in patients with chronic obstructive pulmonary disease

Background: Patients with chronic obstructive pulmonary disease have an increased inspiratory work, since they must overcome high loads due to increased airway resistance. Aim: To determine if the reduction in the metabolic cost of exercise observed in patients with chronic obstructive pulmonary disease (COPD) after inspiratory muscle training, was due to a reduction in the oxygen cost of breathing. Patients and methods: Nine patients with COPD (FEV1 39 ñ 13 percent) subjected to inspiratory muscle training, using a training load of 30 percent of maximal inspiratory pressure, during 10 weeks; 5 patients with COPD (FEV1 44 ñ 18 percent) not subjected to training, and 7 healthy controls (FEV1 110 ñ 10 percent) were studied. The cost of breathing was calculated as the difference in VO2 measured at rest and after breathing a gas mixture containing air and 5 percent CO2. Exercise VO2 was measured at submaximal exercise. Results: Oxygen cost of breathing was increased in patients with COPD and it was inversely correlated with FEV1 (r= -0.86 p<0.001). Inspiratory muscle training increased maximal inspiratory pressure and decreased exercise VO2. Oxygen cost of breathing increased in six and decreased in three trained patients. Changes in this parameter after training did not correlate with the reduction in exercise VO2 or the increment in maximal inspiratory pressure. Conclusions: The reduction in exercise VO2 after inspiratory muscle training is not due to a reduction in the oxygen cost of breathing

Metabolismo de peróxidos en músculos respiratorios: efecto del crecimiento, desarrollo y envejecimiento / Glutathione peroxidase and catalase activity in rat respiratory muscles: effect of growth, maturation and aging

Background: Glutathione peroxidase (GSHPx) and catalase are two important cellular antioxidant enzymes involved in H2O2 and lipid-peroxide metabolism. Aim: To study the effects of growth, maturation and aging on the activity of these enzymes. Material and methods: GSHPx and catalase specific activities were measured in samples of diaphragm and intercostal muscle of male Sprague-Dawley rats of different ages (21, 50, 70, 180 and 365 days), anesthetised with chloral hydrate (45 mg/100 g ip). Results: The diaphragm and intercostal muscles did not differ in GSHPx activity at 21 days. After that, GSHPx activity increased progressively with age, but following a different pattern, in each muscle, suggesting an increase in enzyme substrates with age. In one year old animals, GSHPx activity was 5 times higher for the diaphragm and 3 times higher for the intercostal muscles, when compared with values observed at 21 days of age. Catalase activity also increased with age in the diaphragm but not in the intercostal muscles. Conclusions: GSHPx activity increases progressively with age in rat respiratory muscles, with a time course that is specific of each muscle. Catalase activity increases with age only in the diaphragm. These results support the hypothesis that antioxidants in respiratory muscles undergo specific regulatory changes with age

Enfisema pulmonar experimental en la rata: fenómenos inflamatorios y progresión del daño pulmonar / Experimental pulmonary emphysema in the rat: inflammatory phenomena and progression of lung damage

Background: Although the hamster model of elastase induced emphysema is well characterized, the rat model has received less attention. Aim: To evaluate the effect of a single intratracheal elastase dose on lung pathological changes of Sprague-Dawley rats. Material and methods: Rats were injected with a single intratracheal elastase dose of 28 U/100 g body weight or saline and studied 7, 15, 30 and 365 days after injection. Results: Forty percent of rats died in the first 48 hours after injection, six were sacrificed at 7 days, 6 at 15 days, 7 at 30 days and 12 at 365 days. Progressive centroacinar emphysema was found from day 7 after elastase, with a persistent inflammatory reaction in the vicinity of emphysematous areas. Conclusions: Present findings differ from the panacinar emphysema described in the hamster using a similar elastase dose

Entrenamiento muscular inspiratorio en pacientes con enfermedad pulmonar obstructiva crónica / Inspiratory muscle training in patients with chronic obstructive pulmonary disease

We analyze the effect of inspiratory muscle training (IMT) in patients with chronic obstructive pulmonary disease (COPD), with special emphasis on its effects on inspiratory muscle function and clinical outcomes. We reviewed only randomized, controlled studies that have either controlled both the load and the breathing pattern when using resistive training or have employed a threshold trainer in which the load is independent of the pattern of breathing, since methodological aspects may explain inconsistent results in the literature. In these circumstances, most of the studies demonstrated positive effects on inspiratory muscle function. Clinical effects were seldom evaluated; limited available data showed a reduction in dyspnea that was related to an increase in maximal inspiratory pressures (PIMax). When exercise capacity was evaluated through the distance the patients were able to walk in 6 or 12 minutes, most studies demonstrated a significant increase. Other reported positive effects were improvement in nocturnal SaO2, inspiratory muscle power output and maximal inspiratory flow rate. Based in this review, a recommended training regime appears to be an intermediate load (30-40 percent PIMax) using a threshold device for 30 minutes daily for at least 5 weeks. Although in the literature the criteria for selecting patients are not always well defined, we consider IMT as a helpful procedure for pulmonar rehabilitation in those patients with a moderately severe inspiratory muscle dysfunction presenting dyspnea during daily living activities despite optimal therapy