Nivel sérico de folato y vitamina B12 en adultos mayores chilenos: Resultados de la Encuesta Nacional de Salud ENS 2009-2010 / Serum folate and vitamin B12 in older people: Results from the Chilean national health survey 2009-2010

Supraphysiological levels (SFL) of serum folate (SF) derived from flour fortification with folic acid (FA) could be risky among older adults with low vitamin B12 (B12) levels. Aim: To describe and analyze SF and B12 levels in older Chileans and to identify risk groups. Material and Methods: Participants were 1.043 older people aged ≥ 65 years from the National Health Chilean Health Survey 2009-2010 (ChNHS 2009-10), a multistage stratified random sample, representative of the national population. SF (µg/L) and B12 (pg/ml) were determined in fasting samples by competitive chemoluminescence immunoassay. Mean, deciles and percentiles 5 and 95th were calculated. We defined SF categories: < 4.4 (deficit); 4.41-20 (normal) and SFL: 20.01-25.6; 25.6-29 and > 29 µg/L (80th percentile of the distribution) and vitamin B12 categories: ≤ 200 (deficit); 200.1-299.5 (marginal deficit) and > 299.5 (normal). Prevalence rates, multiple and logistic regression models were used and adjusted by sex and age, educational level and residence area. Results: SF and B12 mean and 95th percentiles were 21.2 ± 0.56/38.6 µg/L and 348.4 ± 7.6/637(pg/ml) respectively. Forty nine percent of participants had SFL. Folate and B12 deficiency were present in 0.3 and 8.1% of participants, respectively. Men had significantly lower prevalence of SFL > 29 µg/L (OR adjusted odds ratio 0.47 95% confidence intervals: 0.26-0.84). B12 showed no significant variation by age and sex. The prevalence of SFL associated with B12 deficiency was 4.1%. No statistically significant association was observed between levels of folate and B12. Conclusions: Folate deficit is almost inexistent, but a significant percentage of participants had SFL suggesting the need for revising the current wheat flour fortification levels.

Aproximación al patrón de normalidad de TSH para la población chilena según Encuesta Nacional de Salud 2009-2010 / Thyroid stimulating hormone reference values derived from the 2009-2010 Chilean National Health Survey

Background: The determination ofthyroid stimulating hormone (TSH) reference values is critical for the diagnosis ofthyroid diseases. Aim: To explore and discuss different definitions to establish TSH reference values using a Chilean national survey sample. Material and Methods: The 2009-2010 Chilean National Health Survey recruited 5,416participants between the ages of 15 and 96years, from all geographic regions of Chile, including urban and rural zones. TSH was measured in a random subsample of 2,785 adults. Median value, 2.5 and 97.5 percentiles were described in three different populations: total survey population, "disease-free population" and the "laboratory kit disease free population". Results: TSH values were higher among women, the elderly and the less educated population. The 97.5 percentile value in the disease-free population was 7.46 uUl/ml. Using this value as a cut-off, hypothyroidism prevalence would be 4.8% in Chile and estimated pharmacological treatment coverage would be 58%. When laboratory kit cut-offs are used, prevalence rises to 22% and treatment coverage drops to 12%. The 2.5 percentile value in the disease-free population was 0.83 uUl/ml, which yields an estimated hyperthyroidism prevalence of3.89%. Conclusions: Median TSH concentration values in the Chilean "disease-free population" are higher than those proposed by laboratory kits and those of developed countries. TSH values in the general population of Chile are also higher in women, the elderly and the less educated population.

Influencia de la obesidad en los costos en salud y en el ausentismo laboral de causa médica en una cohorte de trabajadores / Influence of obesity on health care costs and absenteeism among employees of a mining company

Background: The health associated costs of obesity can represent between 2 percent and 9 percent of the total health costs of a given country. Aim: To assess the impact of obesity on health care costs and absenteeism in a cohort of mine workers. Patients and wethods: Prospective study of 4.673 men, employees of a mining company, aged 49 ± 7 years that were followed for 24 ± 11 months. Total health care cost and days of sick leave were recordedfor each individual. The association between obesity and these variables was analyzed by logistic regression adjusting for co-morbidities, age and other variables. Results: Mean annual health care costs for obese workers were 17 percent higher (p <0.001) compared to workers with normal weight and 58 percent higher (p <0.001) for workers with severe and morbid obesity. Mean annual days of sick leave increased by 25 percento in the obese (p =0.002) and by 57 percento in subjects with severe and morbid obesity (p <0.001). For health care costs the most significant predictors were: presence of diabetes mellitus (Odds ratio (OR) 6.21, 95 percento confidence intervals (95 percent CI) 4.9 to 7.9), hypertension (OR 3-99; 95 percent CI3-4 to 4.6) and severe and morbid obesity (OR 2.55, 95 percento CI 1.9 to 3-4). For absenteeism the most significant predictors were: presence of diabetes mellitus (OR 1.58, 95 percent> CI 1.2 to 2.0), hypertension (OR 1,34, 95 percent> CI 1.2 to 1.6) and severe and morbid obesity (OR 1.50, 95 percento CI 1.1 to 2.1). Conclusions: Obesity increases significantly health care costs and absenteeism.