Nallamothu B K, Fendrick A M, Rubenfire M, Saint S, Bandekar R R, Omenn G S
Division of General Medicine, University of Michigan Medical Center, 3116 Taubman Center, Ann Arbor, MI 48109-0376, USA.
Arch Intern Med. 2000;160(22):3406-12. doi: 10.1001/archinte.160.22.3406.
Elevated total homocyst(e)ine levels (>/=11 micromol/L) have been identified as a potential risk factor for coronary heart disease. However, the benefits expected from lowering homocyst(e)ine levels with folic acid and vitamin B(12) supplementation have yet to be demonstrated in clinical trials.
We constructed a decision analytic model to estimate the clinical benefits and economic costs of 2 homocyst(e)ine-lowering strategies: (1) "treat all"-no screening, daily supplementation with folic acid (400 microg) and vitamin B(12) (cyanocobalamin; 500 microg) for all; (2) "screen and treat"-screening, followed by daily supplementation with folic acid and vitamin B(12) for individuals with elevated homocyst(e)ine levels. Simulated cohorts of 40-year-old men and 50-year-old women in the general population were evaluated. In the base-case analysis, we assumed that lowering elevated levels would reduce excess coronary heart disease risk by 40%; however, this assumption and others were evaluated across a broad range of potential values using sensitivity analysis. Primary outcomes were discounted costs per life-year saved.
Although the treat-all strategy was slightly more effective overall, the screen and treat strategy resulted in a much lower cost per life-year saved ($13,600 in men and $27,500 in women) when compared with no intervention. Incremental cost-effectiveness ratios for the treat-all strategy compared with the screen and treat strategy were more than $500,000 per life-year saved in both cohorts. Sensitivity analysis showed that cost-effectiveness ratios for the screen and treat strategy remained less than $50,000 per life-year saved under several unfavorable scenarios, such as when effective homocyst(e)ine lowering was assumed to reduce the relative risk of coronary heart disease-related death by only 11% in men or 23% in women.
Homocyst(e)ine lowering with folic acid and vitamin B(12) supplementation could result in substantial clinical benefits at reasonable costs. If homocyst-(e)ine lowering is considered, a screen and treat strategy is likely to be more cost-effective than universal supplementation. Arch Intern Med. 2000;160:3406-3412.
总同型半胱氨酸水平升高（≥11微摩尔/升）已被确定为冠心病的一个潜在危险因素。然而，通过补充叶酸和维生素B12来降低同型半胱氨酸水平所预期的益处尚未在临床试验中得到证实。
我们构建了一个决策分析模型，以估计两种降低同型半胱氨酸策略的临床益处和经济成本：（1）“全部治疗”——不进行筛查，所有人每日补充叶酸（400微克）和维生素B12（氰钴胺；500微克）；（2）“筛查并治疗”——进行筛查，随后对同型半胱氨酸水平升高的个体每日补充叶酸和维生素B12。对一般人群中40岁男性和50岁女性的模拟队列进行了评估。在基础病例分析中，我们假设降低升高的水平将使冠心病额外风险降低40%；然而，使用敏感性分析在广泛的潜在值范围内对这一假设及其他假设进行了评估。主要结局是每挽救一个生命年的贴现成本。
尽管“全部治疗”策略总体上略为有效，但与不进行干预相比，“筛查并治疗”策略每挽救一个生命年的成本要低得多（男性为13,600美元，女性为27,500美元）。与“筛查并治疗”策略相比，“全部治疗”策略的增量成本效益比在两个队列中均超过每挽救一个生命年500,000美元。敏感性分析表明，在几种不利情况下，如假设有效的同型半胱氨酸降低仅使男性冠心病相关死亡的相对风险降低11%或女性降低23%时，“筛查并治疗”策略的成本效益比仍低于每挽救一个生命年50,000美元。
补充叶酸和维生素B12降低同型半胱氨酸水平可在合理成本下带来显著的临床益处。如果考虑降低同型半胱氨酸水平，“筛查并治疗”策略可能比普遍补充更具成本效益。《内科学文献》。2000年；160:3406 - 3412。
