Densidade mineral óssea associada a características físicas e estilo de vida em adolescentes

Abstract

Introduction: Just a few studies have evaluated physical traits, lifestyle and bone mineral density (BMD) acquisition in Brazilian female adolescents. Objective: To identify physical traits and lifestyle factors related to BMD in Brazilian female adolescents. Methods: 329 healthy adolescent girls aged between 10 and 20 years participated in this study. The physical characteristics evaluated were: body weight, stature, body mass index, pubertal stage, self-declared ethnicity and skin color. Concerning lifestyle, the following factors were evaluated: socioeconomic status (SES), physical activity level (PAL) and daily calcium intake. Additionally, total body, lumbar spine and femoral neck bone mineral density (BMD) was assessed by bone densitometry. Pearson's coefficient of correlation (r) and stepwise regression analysis were employed to check dependent and independent variables correlation (p ≤ 0.05). Results: Total body, lumbar spine and femoral neck BMD increase as body weight, height, BMI, age and pubertal stage increase (r ≥ 0.43; p<0.01). On the other hand, only SES (r = 0.14; p<0.05) and PAL (r = 0.12; p<0.05) were correlated. After stepwise regression, body weight, pubertal stage, age, height, calcium intake, SES, and PAL explained around 48-68% for BMD variation in female adolescents. Conclusion: The results suggest body weight, age and pubertal stage should be used as control variables for BMD variations in female adolescents. Furthermore, SES, PAL and daily calcium intake were less important than physical traits for BMD during adolescence.

Predictors of Bone Mineral Density in Adolescents With Excess Weight

“…16 Increased daily calcium and protein intake and prevention of vitamin D insufficiency have a potential impact on improving and maintaining bone health and protecting against fractures at all stages of life. 20,2 However, in the adolescents evaluated here, we found no BMD correlations with micronutrient intake; results that are in line with other studies, 3,25 and with the serum concentration of vitamin D. It should be noted that persistent vitamin D inadequacy during the entire adolescence stage can prevent the ideal peak of bone mass set for adulthood. 26 Vitamin D is an essential nutrient, which plays an important role in calcium homeostasis and bone health.…”

“…Similar results are described in obese adolescents of both genders. 3,15 The data available in the literature regarding the relationship between fat mass markers and BMD are conflicting. Some studies describe both FMI 5 and FM 16 as bone mass predictors in female adolescents (regardless of nutritional status).…”

“…2 Body weight, age and sexual maturation can be considered as the main factors related to bone mass during adolescence. 3 The variation in peak bone mass is explained by numerous factors, such as gender, race, dietary habits and physical activity, hereditary factors, hormonal factors, presence of intercurrent diseases, chronic use of medications and body composition characteristics.4 Adiposity excess, although associated with increased bone size, can have an adverse effect on its quality. 2 Increased body weight interferes with both bone mass acquisition and loss and is directly linked to the risk of being overweight or obese.…”

“…While just under 1% of children and adolescents aged 5 to 19 were obese in 1975, more than 124 million children and adolescents (6% of girls and 8% of boys) were obese in 2016, which requires immediate public health actions. 6 When considering that: (a) obesity and osteoporosis are serious global public health issues, 2,6 (b) overweight and its comorbidities are increasingly present in early stages of the life cycle, 1,6 (c) the higher life expectancy led to an increased prevalence of osteoporosis and fractures 4 and (d) there is a correlation between body weight and bone mass development, 3,4 this research was conducted with the main objective of analyzing bone mass and its relationship with nutritional status and serum vitamin D concentration in overweight adolescents.…”