Obesity measured as percent body fat, relationship with body mass index, and percentile curves for Mexican pediatric population.

In Mexico, the increase in childhood obesity is alarming. Thus, improving the precision of its diagnosis is expected to impact on disease prevention. We estimated obesity prevalence by bioimpedance-based percent body fat (%BF) and body mass index (BMI) in 1061 girls and 1121 boys, from 3 to 17 years old. Multiple regressions and area under receiver operating curves (AUC) were used to determine the predictive value of BMI on %BF and percentile curves were constructed. Overall obesity prevalence estimated by %BF was 43.7%, and by BMI it was 20.1%; it means that the diagnosis by BMI underestimated around 50% of children diagnosed with obesity by %BF (≥30% for girls, ≥25% for boys). The fat mass excess is further underestimated in boys than in girls when using the standard BMI classification. The relationship between %BF and BMI was strong in school children and adolescents (all cases R2>0.70), but not in preschool children (girls R2 = 0.57, boys R2 = 0.23). AUCs showed greater discriminative power of BMI to detect %BF obesity in school children and adolescents (all cases AUC≥0.90) than in preschool children (girls AUC = 0.86; boys AUC = 0.70). Growth percentile charts showed that girls aged 9-17 years and boys aged 8-17 years presented fat excess from the 50th percentile and above. We suggested to change the BMI cut-off for them, considering values at the 75th percentile as overweight, and values at the 85th percentile as obesity, as previously recommended for Mexican children. Improving obesity diagnosis will allow greater efficiency when searching for comorbidities in clinical practice.

[Reduction in requirements of oral calcium and 1-25 dihydroxy vitamin D in patients with post-surgical hypoparathyroidism treated with teriparatide (PTH1-34)]. / Reducción en los requerimientos de calcio oral y de 1-25 dihidroxi-vitamina D en pacientes con hipoparatiroidismo posquirúrgico tratados con teriparatida (PTH1-34).

The objective of the study is to evaluate the effect of daily administration of recombinant parathyroid hormone (PTH1-34), 20 µg, on serum calcium concentrations (Cas), and the requirements of oral calcium and calcitriol in patients with hypoparathyroidism. It is a prospective, longitudinal study, analytical, with intervention, in patients treated with high doses of calcium (> 7 g/day), with symptoms of hypocalcemia and/or intolerant to treatment. Serum levels of phosphorus (Ps) and Cas, urinary calcium excretion, oral doses of calcitriol and calcium were compared before and after administration of teriparatide, for three months on average, in patients with post-surgical hypoparathyroidism. We studied 16 patients with oral elemental calcium requirements of 22.5 ± 16 g/day of calcitriol 0.79 ± 0.4 µg/day. Cas at baseline was 7.6 ± 1.2 and Ps 5.4 ± 0.76 mg/dl. After administration of teriparatide, Cas was 9.0 ± 0.69 mg/dl (p = 0.007) and Ps of 4.5 ± 0.87 mg/dl (p = 0.003). Doses of calcium and calcitriol showed a statistically significant reduction (p = 0.0001 and 0.001, respectively). We conclude that use of recombinant parathyroid hormone can normalize Cas and Ps, with reduction in oral calcium and calcitriol requirements.

Sleep apnea in patients with acromegaly. Frequency, characterization and positive pressure titration.

OBJECTIVES: to describe the frequency of sleep apnea in patients with acromegaly;to identify the proportion of candidates for treatment with positive airway pressure;to report our experience with the positive pressure titration process in acromegaly patients. METHODS: A cross-sectional study that included the acromegaly cohort at the Centro Medico Nacional "20 de Noviembre" in Mexico City (n=44). A standard polysomnography (PSG) was carried out for each patient. A second PSG was done for purposes of CPAP titration. RESULTS: A total of 35 patients were studied (80% of the cohort, 20 [57%] women). Polysomnography results showed that 34 subjects (97%, 95%CI 91-100%) had apnea hypopnea indexes (AHI) ≥ 5. No patient had central apnea. We identified 19 subjects with AHI ≥5 and Epworth ≥10, for a frequency of obstructive sleep apnea syndrome of 54% (95%CI 36-71%). A total of 31 patients (88%; 95%CI 77-99%) were deemed to be candidates for positive pressure treatment, but only 8 of them accepted CPAP. They required pressures that ranged from 10 to 18 cmH(2)O. CONCLUSIONS: Our results confirm a high prevalence of sleep apnea in patients with acromegaly, and provide evidence that the majority of those patients are candidates for treatment with positive pressure. Contrary to what has been reported, we identified no patients with central apnea.

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