Powars D R, Weiss J N, Chan L S, Schroeder W A
Blood. 1984 Apr;63(4):921-6.
When the clinical manifestations of 272 patients with sickle cell anemia are compared with their level of fetal hemoglobin (HbF), the results suggest that there may be a threshold above which HbF is effective in ameliorating the morbidity of this disease. The age of entry of these SS patients into the study ranged from birth to 56 yr; the average length of follow-up was 11 yr for a total of 3,011 patient-years of clinic observation. HbF was determined quantitatively by microchromatographic procedures; the mean for HbF was 10% +/- 6% with a range from 2% to 32%. For major organ failure, analyzed as termination events of morbidity, such as stroke or aseptic necrosis, the threshold appears to be 10%, whereas for recurrent clinical events, such as crisis or pulmonary disorders, it is 20%. No linear trend was found between HbF levels and morbidity. If a threshold exists, it is important to recognize this fact when attempts are made to raise the level of HbF in patients with sickle cell disease.
当将272例镰状细胞贫血患者的临床表现与其胎儿血红蛋白（HbF）水平进行比较时，结果表明可能存在一个阈值，高于此阈值时HbF可有效减轻该疾病的发病率。这些镰状细胞贫血（SS）患者进入研究的年龄范围从出生到56岁；平均随访时间为11年，总计3011患者年的临床观察。通过微量色谱法对HbF进行定量测定；HbF的平均值为10%±6%，范围为2%至32%。对于作为发病终止事件进行分析的主要器官衰竭，如中风或无菌性坏死，阈值似乎为10%，而对于复发性临床事件，如危象或肺部疾病，阈值为20%。未发现HbF水平与发病率之间存在线性趋势。如果存在阈值，那么在试图提高镰状细胞病患者的HbF水平时，认识到这一事实很重要。
