北京市社区中老年男性体重指数和前列腺特异性抗原相关性的多中心研究

Relationship between serum prostate-specific antigen levels and body mass index in Beijing men over 50 years of age

目的了解北京地区中老年男性人群体重指数（BMI）和前列腺特异性抗原（PSA）的相关性。方法选择北京社区50岁以上男性作为研究对象，行体格检查并计算体重指数（BMI），按WHO提出的亚洲人体重分级建议进行BMI分层，测血清总前列腺特异性抗原（TPSA）及游离前列腺特异性抗原（FPSA），应用SPSS13．0统计软件对BMI和TPSA的相关性进行统计学分析。结果符合标准并资料全面者1573人，平均年龄（64±10）岁，平均BMI：（24±3）kg／m^2，PSA中位数：1．0μg／L（0．6—1．9μg／L），平均前列腺体积：（30±18）ml^3。BMI分级：低体重54例（3．43％），正常体重441例（28．04％），超重423例（26．89％），肥胖597例（37．95％），重度肥胖58例（3．69％）。正常组和超重组分别与肥胖组PSA比较差异均有统计学意义（P=0．002、0．010）。在调整年龄和前列腺体积情况下，BMI和PSA呈负相关（r=-0.068，P=0.007）。年龄及前列腺体积与PSA呈正相关（r=0.204，P=0.030；r=0．401，P=0．000）。在不同年龄分层，各年龄组之间BMI和PSA均不相关（均P〉0.1）。结论BMI影响血清PSA结果，BMI和PSA呈负相关。在前列腺癌诊断时，应当考虑BMI对PSA的影响。

Objective To investigate the relationship between body mass index （BMI） and serum prostate specific antigen （PSA）. Methods A cross-sectional study was performed at community of Beijing in men over 50 years old. Height, weight and PSA （both serum TPSA and FPSA） were assessed in 1573 men. According to the redefined World Health Organization （WHO） criterion for Asia Pacific Region, BMI was categorized as light weight （BMI 〈 18.5 kg/m^2）, normal （18.5 kg/m^2 ≤ BMI 〈 23.0 kg/m^2）, overweight （ 23.0 kg/m^2 ≤ BMI 〈 25.0 kg/m^2 ）, obese （ 25.0 kg/m^2 ≤ BMI 〈 30. 0 kg/m^2 ） and severe obese （BMI ≥30 kg/m^2 ）. SPSS 13.0 was used in BMI and PSA statistical analysis. Results Mean age was （64 ±10） years, mean BMI （24 ±3） kg/m^2, PSA median 1.0（0. 6 - 1.9） μg/L and mean prostate volume（30 ±18） ml. BMI classification ： low weight 54 cases （ 3.43% ）, normal weight 441 （28.04%）, overweight 423 patients （26. 89% ）, obesity 597 patients （37.95%） and severe obesity 58 （3.69%）. We adjusted the low weight group and severe obesity group into normal group and obesity group respectively for small sample capacity. After adjustment, there was no significance difference （ P = 0. 75 ） between PSA level of normal group and that of obesity group. However, the PSA level of normal group and overweight group versus obesity group respectively, there were significant differences （P = 0. 002, 0. 010）. After adjusting for age and prostate volume, the correlation between BMI and PSA was negative. BMI showed no significant correlation with PSA in different age groups. Conclusion BMI and PSA were negatively correlated. BMI should be considered as a factor （esp. for obese or severe obese） in man undergoing prostate cancer screening.