Teen Obesity May Cause Permanent Skeletal Dysregulation

High visceral adipose tissue (VAT) mass and low lean mass are risk factors for skeletal dysregulation in adolescents with morbid obesity, according to a study presented at RSNA 2016.

Researchers from Massachusetts General Hospital and Harvard Medical School in Boston sought to determine predictors of trabecular and cortical microarchitecture of the distal radius in adolescents with morbid obesity. "While obesity was previously believed to be protective of bone health, recent studies have shown a higher incidence of forearm fractures in obese youths," lead author, Miriam A. Bredella, MD, said in a release.

Twenty-three adolescents, mean age 17, with morbid obesity participated in the study. Their mean body mass index (BMI) was 44 kg/m². All were to undergo 3D HR-pQCT to measure bone mineral density and bone microarchitecture in the arms and legs. They also underwent dual-energy X-ray absorptiometry (DXA) exams to determine body composition, including lean mass and visceral fat mass. Two subject were unable to undergo HR-pQCT due to body size.[[{"type":"media","view_mode":"media_crop","fid":"54274","attributes":{"alt":"Miriam A. Bredella, MD","class":"media-image media-image-right","id":"media_crop_3438229222273","media_crop_h":"0","media_crop_image_style":"-1","media_crop_instance":"6792","media_crop_rotate":"0","media_crop_scale_h":"0","media_crop_scale_w":"0","media_crop_w":"0","media_crop_x":"0","media_crop_y":"0","style":"height: 225px; width: 170px; border-width: 0px; border-style: solid; margin: 1px; float: right;","title":"Miriam A. Bredella, MD","typeof":"foaf:Image"}}]]

The results showed that BMI was positively associated with cortical thickness and cortical area. Lean mass was positively associated with trabecular density and volume, and measures of trabecular integrity by individual trabecular segmentation (ITS). VAT mass was positively associated with cortical porosity.

The researchers concluded that lean mass is a positive predictor of measures of trabecular integrity, whereas VAT is a negative predictor of cortical integrity in adolescents with morbid obesity. "The best way to prevent bone loss is a healthy diet that contains adequate amounts of calcium and vitamin D, along with sufficient exercise, as we have shown in our study that muscle mass is good for bone health," Bredella explained in the release.