May 13, 2010 (英屬哥倫比亞溫哥華) — 根據發表於小兒科協會2010年會的新研究，過重小孩的脂質數值風險較大，意味著他們的心血管疾病風險較高。
發表人、北卡羅來納大學教堂山分校醫學院一般小兒科與青少年醫學系小兒科助理教授Asheley C. Skinner博士向Medscape Pediatrics表示，在各年齡層，過重孩童的各項脂質數據都比健康體重的小孩差，再者，這些差異隨著年紀更加明顯，特別是青春期。
研究者分析了自1999至2006年的「National Health and Nutrition Education Survey (NHANES)」研究之部份資料獲得這項結論，測量孩童與青少年空腹至少8小時後的總膽固醇(TC)、低密度脂蛋白(LDL)、高密度脂蛋白(HDL)與三酸甘油脂，如果研究對象的身體質量指數(BMI)超過第85百分位則被歸類為過重，如果BMI 介於第5-85百分位則被視為健康體重。
Early, Persistent Differences in Cholesterol Levels Between Overweight and Healthy Weight Children
By Brian Hoyle
Medscape Medical News
May 13, 2010 (Vancouver, British Columbia) — Children who are overweight run a greater risk of having lipid profiles that signal a high risk for cardiovascular disease, and risk gets progressively higher with age, according to new research presented here at the Pediatric Academic Societies 2010 Annual Meeting.
"Overweight children have worse lipid profiles than healthy [weight] children for all lipid components at all ages of childhood. Moreover, the differences become more pronounced with age, particularly around the time of puberty," study presenter Asheley C. Skinner, PhD, assistant professor of pediatrics, Department of General Pediatrics and Adolescent Medicine, University of North Carolina at Chapel Hill School of Medicine, told Medscape Pediatrics.
To reach this conclusion, the researchers analyzed data compiled as part of the National Health and Nutrition Education Survey (NHANES) from 1999 to 2006. Total cholesterol (TC), low-density lipoproteins (LDL), high-density lipoproteins (HDL), and triglycerides were measured in children and adolescents after a fast of at least 8 hours. The participants were categorized as overweight if their body mass index (BMI) exceeded the 85th percentile and as healthy weight if their BMI ranged from the 5th to the 85th percentile.
The overweight group consisted of 1959 children 3 to 17 years of age and the healthy weight group consisted of 3119 age-matched counterparts.
The data were examined using least mean square smoothing, in which mean and variance values are used to create curves across age.
Although the curves cannot be used to examine differences in individuals with age, an "acknowledged limitation of cross-sectional data," Dr. Skinner said, it offers a powerful means of viewing changes in populations over time.
Dr. Skinner's team constructed curves for TC, LDL, HDL, and fasting triglycerides, plotting data for girls and boys who were overweight (the 95th percentile was selected) and healthy weight (the 75th percentile was selected).
In general, all curves displayed the same undulating pattern, with an initial trough followed by a climb to a peak that, depending on the lipid, varied in actual value and time (8 to 11 years), followed by a trough that varied in slope and, finally, by a variable rise for those aged 16 and 17 years of age, Dr. Skinner reported.
In the TC, LDL, and triglyceride curves, the pattern was similar, with lipids being elevated in overweight children all along the age range, and the differences becoming more pronounced around adolescence. The situation was reversed in the HDL curves, where the levels of the good cholesterol were consistently higher in the healthy weight children, Dr. Skinner noted.
The situation for triglycerides was particularly dramatic, with a precipitous rise in overweight children beginning at about 4 years of age. The levels were maintained, producing "much, much higher values" in adolescence, Dr. Skinner reported. The levels exceeded 200?mg/dL in overweight children by the time they were about 8 years of age, and consistently increased with age, hitting 250?mg/dL by age 16.
"These results suggest that abnormal lipid values may persist and accumulate in overweight children throughout childhood," said Dr. Skinner.
Although the researchers continue to analyze the available data, teasing out more specific information on specific factors, including ethnicity, a larger database is required.
"We have noticed a similar trend in our North Carolina children," with a study showing that obese children report consuming fewer calories than their healthy weight peers, Robert G. McMurray, MD, professor of exercise and sport science and professor of nutrition at the University of North Carolina, in Durham, told Medscape Pediatrics.
"If the caloric intake is low, the resting metabolic rates of the obese children may be lower than normal; there are some data to support this. Alternatively, the obese children may be less active and require fewer calories, [leading to] a lower resting metabolic rate. If their resting metabolic rates are lower and they are less active, then it is easy to see how they could remain obese," Dr. McMurray said.
Dr. McMurray's research also shows that elevated cholesterol levels in obese children are independent of physical activity.
The study was funded by grants from the National Institute of Child Health and Development and the Building Interdisciplinary Careers in Women's Health program. The authors have disclosed no relevant financial relationships.
