1 Division of Rheumatology, Columbia University College of Physicians and Surgeons, and New York Presbyterian Hospital, New York, USA.
2 Exagen Laboratory, New York, USA.
Lupus. 2019 Jun;28(7):862-867. doi: 10.1177/0961203319851558. Epub 2019 May 24.
Hydroxychloroquine (HCQ) is a key therapy in systemic lupus erythematosus (SLE). Medication non-adherence is reported in up to 80% of lupus patients and results in increased morbidity, mortality, and health care utilization. HCQ levels are a sensitive and reliable method to assess medication adherence. Our study evaluated the role of HCQ level measurement in routine clinical care and its association with disease activity in a predominantly Hispanic population.
SLE patients from the Columbia University Lupus cohort treated with HCQ for ≥ 6 months and reporting medication adherence were included. HCQ levels were measured by whole blood high performance liquid chromatography. Non-adherence was defined as an HCQ level <500 ng/ml. The association between HCQ levels and disease activity measured by Systemic Lupus Erythematosus Disease Activity Index 2000 (SLEDAI-2K) was evaluated.
One hundred and eight patients were enrolled; the median age was 38 years, 91% were female, and 63% were Hispanic. The median SLEDAI-2K was 4.3 (0-20). Forty-one percent of patients had an HCQ level <500 ng/ml consistent with non-adherence, of which 19% had undetectable levels. A higher SLEDAI-2K score was associated with low HCQ levels ( = 0.003). This association remained significant after adjusting for depression ( = 0.0007).
HCQ levels < 500 ng/ml were associated with higher disease activity and accounted for 32% of the SLEDAI-2K variability. HCQ blood measurement is a simple and reliable method to evaluate medication adherence in SLE. Reasons for non-adherence (levels < 500 ng/ml) should be further explored and addressed.
羟氯喹（HCQ）是系统性红斑狼疮（SLE）的关键治疗药物。多达 80%的狼疮患者存在药物不依从性，这会导致发病率、死亡率和医疗保健利用率增加。HCQ 水平是评估药物依从性的敏感和可靠方法。我们的研究评估了在以西班牙裔为主的人群中，在常规临床护理中测量 HCQ 水平的作用及其与疾病活动的相关性。
纳入了在哥伦比亚大学狼疮队列中接受 HCQ 治疗且报告药物依从性的≥6 个月的 SLE 患者。通过全血高效液相色谱法测量 HCQ 水平。将 HCQ 水平<500ng/ml 定义为不依从。评估 HCQ 水平与系统性红斑狼疮疾病活动指数 2000（SLEDAI-2K）测量的疾病活动之间的相关性。
共纳入 108 例患者；中位年龄为 38 岁，91%为女性，63%为西班牙裔。中位 SLEDAI-2K 为 4.3（0-20）。41%的患者 HCQ 水平<500ng/ml 提示不依从，其中 19%的患者检测不到 HCQ 水平。更高的 SLEDAI-2K 评分与低 HCQ 水平相关（=0.003）。调整抑郁因素后，这种相关性仍然显著（=0.0007）。
HCQ 水平<500ng/ml 与更高的疾病活动相关，占 SLEDAI-2K 变异性的 32%。HCQ 血液测量是评估 SLE 药物依从性的简单可靠方法。应进一步探讨和解决不依从（水平<500ng/ml）的原因。
