Grace C, Beales P, Summerbell C, Jebb S A, Wright A, Parker D, Kopelman P
Obesity Research Department, Royal London Hospital, London, UK.
Int J Obes Relat Metab Disord. 2003 Nov;27(11):1319-24. doi: 10.1038/sj.ijo.0802420.
Obesity is a consistent presenting feature of the Bardet-Biedl syndrome (BBS), a hereditary disorder caused by a single gene defect. This contrasts sharply with general obesity which, despite a strong hereditary component, has a multifactorial aetiology. For BBS, the phenotypic characterisation of the components of energy balance and the implications for their management remains relatively uninvestigated.
A case-control study to determine whether energy metabolism in subjects with BBS differs from matched obese controls and to inform the clinical management of these patients.
A total of 20 overweight and obese subjects with BBS (11 females, 9 males) matched for age, gender and BMI to 20 subjects without BBS. Resting metabolic rate (RMR) was measured by indirect calorimetry, physical activity by CSA accelerometry, body composition by the deuterium dilution technique and dietary intake by 7-day food records.
There was no significant difference between BBS and control subjects in body fat (male: % fat=38, s.d. 2.8 vs 34, s.d. 9.1, female: % fat=45, s.d. 5.9 vs 44, s.d. 8.1; P=0.46] or absolute RMR (male: 6.95, s.d. 1.55 MJ/day vs 7.19, s.d. 1.28 MJ/day; P=0.6). After adjustment for gender, age, fat-free mass and fat mass, there was no significant difference in RMR between BBS and control subjects (F(1, 30)=0.91; P=0.35). A lower level of physical activity was observed in BBS subjects (median cnts/min 259, IQR=153) compared to controls (median cnts/min=306, IQR=119, P=0.02). Reported energy intake, macronutrient composition and magnitude of under-reporting were comparable in both groups.
This study reveals no evidence for systematic differences in energy metabolism in subjects with BBS relative to other obese individuals, suggesting that the genetic basis of BBS is not associated with specific abnormalities in energy metabolism. This is an important finding for clinical management and supports the use of energy prescriptions based on RMR for the general obese population plus an appropriate allowance for energy expended via physical activity. Further research is needed on physical activity in BBS.
肥胖是巴德-比德尔综合征（BBS）的一个持续存在的特征，这是一种由单基因缺陷引起的遗传性疾病。这与一般肥胖形成鲜明对比，一般肥胖尽管有很强的遗传成分，但其病因是多因素的。对于BBS，能量平衡各组成部分的表型特征及其管理意义仍相对缺乏研究。
进行一项病例对照研究，以确定BBS患者的能量代谢是否与匹配的肥胖对照者不同，并为这些患者的临床管理提供信息。
总共20名超重和肥胖的BBS患者（11名女性，9名男性），在年龄、性别和体重指数方面与20名非BBS患者相匹配。静息代谢率（RMR）通过间接测热法测量，身体活动通过CSA加速度计测量，身体成分通过氘稀释技术测量，饮食摄入量通过7天食物记录测量。
BBS患者和对照者在体脂方面无显著差异（男性：体脂百分比=38，标准差2.8对34，标准差9.1；女性：体脂百分比=45，标准差5.9对44，标准差8.1；P=0.46），绝对RMR也无显著差异（男性：6.95，标准差1.55兆焦/天对7.19，标准差1.28兆焦/天；P=0.6）。在对性别、年龄、去脂体重和脂肪量进行调整后，BBS患者和对照者的RMR无显著差异（F(1, 30)=0.91；P=0.35）。与对照者相比，观察到BBS患者的身体活动水平较低（中位数计数/分钟259，四分位间距=153）（对照者：中位数计数/分钟=306，四分位间距=119，P=0.02）。两组报告的能量摄入量、宏量营养素组成和报告不足的程度相当。
这项研究没有发现证据表明BBS患者的能量代谢与其他肥胖个体存在系统性差异，这表明BBS的遗传基础与能量代谢的特定异常无关。这是临床管理中的一项重要发现，并支持基于RMR为一般肥胖人群开具能量处方，并适当考虑通过身体活动消耗的能量。需要对BBS患者的身体活动进行进一步研究。
