Hart D J, Doyle D V, Spector T D
Twin Research and Osteoporosis Unit, St. Thomas' Hospital, London, UK.
Arthritis Rheum. 1999 Jan;42(1):17-24. doi: 10.1002/1529-0131(199901)42:1<17::AID-ANR2>3.0.CO;2-E.
To examine the natural history, role of risk factors, and incidence of knee osteoarthritis (OA) in a prospective study of women from a population cohort.
Women from the Chingford Study who had been recruited in 1989 were followed up with knee radiographs 4 years later. A total of 715 paired radiographs (71% of the original sample) were graded for osteophytes and 644 for joint space narrowing (JSN). Women whose radiographs had been graded as 0 in 1989 and as > or =14 years later were classified as having incident disease. Incident cases were compared with controls for associations with a number of risk factors.
Eighty-one women (12.6%) developed JSN of the knee, equating to an incidence of 3.1% per year. No clear risk factors for JSN were identified. Reproducibility of measures of joint space is poor, however, leading to inaccuracy of definition. Incident knee osteophytes developed in 95 women (133%), equating to an incidence of 3.3% per year. Compared with controls, women with incident knee osteophytes were older, heavier, and had more hand OA and knee symptoms. Women in the top tertile of obesity (body mass index >26.4) had a significantly increased risk of incident knee osteophytes (odds ratio [OR] 2.38, 95% confidence interval [95% CI] 1.29-4.39). Incident knee osteophytes increased by 20% per 5-year age increase. A nonsignificant protective effect for incident knee osteophytes was seen with current estrogen replacement therapy (ERT) (OR 0.41, 95% CI 0.12-1.42). No effect was associated with smoking, physical activity, hysterectomy, or previous knee injury.
Obesity and aging are associated with a high risk of new knee OA developing in women. Evidence of a protective effect of ERT was seen. No clear association was found for incident JSN, suggesting that different etiologic mechanisms are operating or that standard radiographs are an inaccurate measure of incident narrowing.
在一项针对人群队列中女性的前瞻性研究中，研究膝关节骨关节炎（OA）的自然病史、危险因素的作用及发病率。
对1989年招募的来自钦福德研究的女性进行随访，4年后拍摄膝关节X线片。共对715对X线片（占原始样本的71%）进行骨赘分级，对644对进行关节间隙狭窄（JSN）分级。1989年X线片分级为0且14年后分级为≥1的女性被归类为发生了新发疾病。将新发病例与对照组比较，分析与多种危险因素的关联。
81名女性（12.6%）出现膝关节JSN，相当于年发病率为3.1%。未发现JSN的明确危险因素。然而，关节间隙测量的可重复性较差，导致定义不准确。95名女性（13.3%）出现新发膝关节骨赘，相当于年发病率为3.3%。与对照组相比，发生新发膝关节骨赘的女性年龄更大、体重更重，手部OA和膝关节症状更多。肥胖程度处于最高三分位数（体重指数>26.4）的女性发生新发膝关节骨赘的风险显著增加（比值比[OR]2.38，95%置信区间[95%CI]1.29 - 4.39）。每增加5岁，新发膝关节骨赘增加20%。目前的雌激素替代疗法（ERT）对新发膝关节骨赘有不显著的保护作用（OR 0.41，95%CI 0.12 - 1.42）。吸烟、体育活动、子宫切除术或既往膝关节损伤与之无关联。
肥胖和衰老与女性发生新发膝关节OA的高风险相关。观察到ERT有保护作用的证据。未发现新发JSN有明确关联，提示存在不同的病因机制，或标准X线片对新发狭窄的测量不准确。
