Christiansen Christian Fynbo, Ehrenstein Vera, Heide-Jørgensen Uffe, Skovbo Stine, Nørrelund Helene, Sørensen Henrik Toft, Li Lin, Jick Susan
Department of Clinical Epidemiology, Aarhus University Hospital, Aarhus N, Denmark.
Boston Collaborative Drug Surveillance Program, Boston University School of Public Health, Lexington, Massachusetts, USA.
BMJ Open. 2015 Sep 2;5(9):e008531. doi: 10.1136/bmjopen-2015-008531.
To estimate prevalence of renal impairment, rate of decline in kidney function and changes in metformin use after decline in kidney function, in metformin initiators.
DESIGN, SETTING AND PARTICIPANTS: We conducted this 2-country cohort study using routine data from northern Denmark and the UK during 2000-2011. We included metformin initiators among patients aged ≥30 years with medically treated diabetes.
We described patients' demographics, comorbidity, co-medications and their estimated glomerular filtration rates (eGFR). Furthermore, we described the patients' characteristics according to eGFR level. Finally, we examined the rate of any decline in eGFR and changes in metformin use within 90 days after first decline in eGFR during follow-up.
We included 124,720 metformin initiators in the 2 countries. Prevalence of eGFR <60 mL/min/1.73 m(2) among metformin initiators was 9.0% in Denmark and 25.2% in the UK. In contrast, prevalence of eGFR values <30 mL/min/1.73 m(2) among metformin initiators was 0.3% in Denmark and 0.4% in the UK. Patients with renal impairment were older and more likely to have received cardiovascular drugs. Incidence rate of decline in renal function was 4.92 per 100 person-years (95% CI 4.76 to 5.09) in Denmark and 7.48 per 100 person-years (95% CI 7.39 to 7.57) in the UK. The proportion of patients continuing metformin use, even after a first decline brought the eGFR below 30 mL/min/1.73 m(2), was 44% in Denmark and 62% in the UK. There was no clinically significant dose reduction with decreasing baseline eGFR level discernible from the data.
Mild to moderate renal impairment was common among metformin initiators, while severe renal impairment was uncommon. Patients with severe renal impairment frequently continued receiving/redeeming metformin prescriptions even 90 days after eGFR decline.
评估二甲双胍起始使用者中肾功能损害的患病率、肾功能下降率以及肾功能下降后二甲双胍使用情况的变化。
设计、研究地点和参与者：我们利用丹麦北部和英国2000年至2011年的常规数据开展了这项两国队列研究。我们纳入了年龄≥30岁且接受药物治疗的糖尿病患者中的二甲双胍起始使用者。
我们描述了患者的人口统计学特征、合并症、联合用药情况及其估算肾小球滤过率（eGFR）。此外，我们根据eGFR水平描述了患者的特征。最后，我们研究了随访期间首次eGFR下降后90天内eGFR的任何下降率以及二甲双胍使用情况的变化。
我们在这两个国家纳入了124,720名二甲双胍起始使用者。二甲双胍起始使用者中eGFR<60 mL/min/1.73m²的患病率在丹麦为9.0%，在英国为25.2%。相比之下，二甲双胍起始使用者中eGFR值<30 mL/min/1.73m²的患病率在丹麦为0.3%，在英国为0.4%。肾功能损害患者年龄较大，更有可能接受过心血管药物治疗。丹麦肾功能下降的发病率为每100人年4.92例（95%CI 4.76至5.09），英国为每100人年7.48例（95%CI 7.39至7.57）。即使首次eGFR下降使eGFR低于30 mL/min/1.73m²后仍继续使用二甲双胍的患者比例，在丹麦为44%，在英国为62%。从数据中无法看出随着基线eGFR水平降低有临床上显著的剂量减少。
轻度至中度肾功能损害在二甲双胍起始使用者中很常见，而重度肾功能损害并不常见。即使在eGFR下降90天后，重度肾功能损害患者仍经常继续接受/领取二甲双胍处方。
