Zhang Yuqing, Terkeltaub Robert, Nevitt Michael, Xu Ling, Neogi Tuhina, Aliabadi Piaran, Niu Jingbo, Felson David T
Boston University Medical Center, Boston University School of Medicine, Boston, Massachusetts 02118, USA.
Arthritis Rheum. 2006 Nov;54(11):3508-12. doi: 10.1002/art.22189.
Chondrocalcinosis, which can promote joint inflammation and cartilage degeneration, is highly prevalent in elderly white subjects. Data on its prevalence are scarce in other ethnic populations. This study was undertaken to compare the prevalence of chondrocalcinosis in Chinese subjects with that in white subjects.
We recruited a random sample of Beijing residents ages >or=60 years. Participants underwent standard weight-bearing anteroposterior knee radiography and posteroanterior hand radiography using the protocols developed in the Framingham Osteoarthritis Study. Radiographic chondrocalcinosis was defined as present in a knee or wrist when there was evidence of definite linear cartilage calcification. We compared the prevalence of chondrocalcinosis in Chinese subjects with that in white subjects using age-standardized prevalence ratios. We used identical methods to collect samples of tap water from 2 cities and measured their levels of calcium, magnesium, and phosphate in the same laboratory.
Chinese subjects had a much lower prevalence of knee chondrocalcinosis (1.8% in men, 2.7% in women) than did white subjects (6.2% in men, 7.7% in women), with the age-standardized prevalence ratio being 0.34 (95% confidence interval [95% CI] 0.20-0.54) and 0.43 (95% CI 0.31-0.59) in men and women, respectively. Wrist chondrocalcinosis was rare in elderly Chinese subjects (prevalence 0.3% in men and 1.0% in women), with the age-standardized prevalence ratio being 0.06 (95% CI 0.01-0.18) in Chinese men and 0.18 (95% CI 0.10-0.30) in Chinese women. Calcium levels in the tap water in Beijing were 15-fold higher than in Framingham, whereas no difference was found in magnesium and phosphate levels.
Knee chondrocalcinosis and wrist chondrocalcinosis are far less common in Chinese subjects in Beijing than in US white subjects in Framingham, Massachusetts. Given the current lack of understanding of the etiology of chondrocalcinosis, further epidemiologic studies of the impact of genetic and environmental factors on occurrence of chondrocalcinosis are indicated.
软骨钙质沉着症可促进关节炎症和软骨退变，在老年白人中极为普遍。关于其在其他种族人群中的患病率数据稀少。本研究旨在比较中国人群与白人人群中软骨钙质沉着症的患病率。
我们随机抽取了年龄≥60岁的北京居民作为样本。参与者按照弗明汉骨关节炎研究制定的方案接受标准负重膝关节前后位X线摄影和手部后前位X线摄影。当有明确的线性软骨钙化证据时，X线片上的软骨钙质沉着症定义为膝关节或腕关节存在该病变。我们使用年龄标准化患病率比来比较中国人群与白人人群中软骨钙质沉着症的患病率。我们采用相同方法从两个城市采集自来水样本，并在同一实验室测量其钙、镁和磷酸盐水平。
中国人群膝关节软骨钙质沉着症的患病率（男性为1.8%，女性为2.7%）远低于白人人群（男性为6.2%，女性为7.7%），男性和女性的年龄标准化患病率比分别为0.34（95%置信区间[95%CI]0.20 - 0.54）和0.43（95%CI 0.31 - 0.59）。老年中国人群腕关节软骨钙质沉着症罕见（男性患病率为0.3%，女性为1.0%），中国男性和女性的年龄标准化患病率比分别为0.06（95%CI 0.01 - 0.18）和0.18（95%CI 0.10 - 0.30）。北京自来水的钙水平比弗明汉高15倍，而镁和磷酸盐水平未发现差异。
北京的中国人群中膝关节和腕关节软骨钙质沉着症的发生率远低于马萨诸塞州弗明汉的美国白人。鉴于目前对软骨钙质沉着症病因缺乏了解，有必要进一步开展关于遗传和环境因素对软骨钙质沉着症发生影响的流行病学研究。
