Mortaz Soroush, Wessman Christine, Duncan Ross, Gray Rachel, Badawi Alaa
Office of Biotechnology Genomics and Population Health, Public Health Agency of Canada, Toronto, Ontario, Canada.
Clinicoecon Outcomes Res. 2012;4:91-7. doi: 10.2147/CEOR.S30547. Epub 2012 Apr 10.
Type 2 diabetes mellitus (T2DM) is a major global health problem. An estimated 20%-50% of diabetic subjects in Canada are currently undiagnosed, and around 20%-30% have already developed complications. Screening for high blood glucose levels can identify people with prediabetic conditions and permit introduction of timely and effective prevention. This study examines the benefit of screening for impaired fasting glucose (IFG) and T2DM. If intervention is introduced at this prediabetic stage, it can be most effective in delaying the onset and complications of T2DM.
Using a Markov model simulation, we compare the cost-effectiveness of screening for prediabetes (IFG) and T2DM with the strategy of no screening. An initial cohort of normoglycemic, prediabetic, or undiagnosed diabetic adults with one or more T2DM risk factors was used to model the strategies mentioned over a 10-year period. Subjects without known prediabetes or diabetes are screened every 3 years and persons with prediabetes were tested for diabetes on an annual basis. The model weighs the increase in quality-adjusted life-years (QALYs) associated with early detection of prediabetes and earlier diagnosis of T2DM due to lifestyle intervention and early treatment in asymptomatic subjects.
Costs for each QALY gained were $2281 for conventional screening compared with $2890 for no screening. Thus, in this base-case analysis, conventional screening with a frequency of once every 3 years was favored over no screening. Furthermore, conventional screening was more favorable compared with no screening over a wide range of willingness-to-pay thresholds. Changing the frequency of screening did not affect the overall results. Screening persons without diabetes or prediabetes on an annual basis had small effects on the cost-effectiveness ratios. Screening with a frequency of once every 5 years resulted in the lowest cost per QALY ($2117). Lack of screening costs the health care system $4812 more than the cost of screening once every 5 years.
The increased cost per QALY of not screening is due to the costs of complications caused downstream of T2DM. By ensuring that IFG screening occurs every 3 years for those without prediabetes and every year for those with prediabetes, the health and financial benefits related to T2DM are improved in Canada.
2型糖尿病（T2DM）是一个重大的全球健康问题。据估计，加拿大目前有20%-50%的糖尿病患者未被诊断出来，约20%-30%已经出现并发症。筛查高血糖水平可以识别出糖尿病前期患者，并能及时采取有效的预防措施。本研究探讨了筛查空腹血糖受损（IFG）和T2DM的益处。如果在糖尿病前期阶段进行干预，对于延缓T2DM的发病和并发症最为有效。
我们使用马尔可夫模型模拟，比较了筛查糖尿病前期（IFG）和T2DM与不进行筛查策略的成本效益。以一组具有一个或多个T2DM危险因素的血糖正常、糖尿病前期或未确诊糖尿病的成年人为初始队列，对上述策略在10年期间进行建模。未患已知糖尿病前期或糖尿病的受试者每3年筛查一次，糖尿病前期患者每年检测是否患有糖尿病。该模型权衡了因生活方式干预和对无症状受试者的早期治疗而早期发现糖尿病前期和更早诊断T2DM所带来的质量调整生命年（QALY）的增加。
常规筛查每获得一个QALY的成本为2281美元，而不进行筛查为2890美元。因此，在本基线分析中，每3年进行一次的常规筛查优于不进行筛查。此外，在广泛的支付意愿阈值范围内，常规筛查也比不进行筛查更有利。改变筛查频率不影响总体结果。每年对未患糖尿病或糖尿病前期的人进行筛查对成本效益比影响较小。每5年筛查一次导致每个QALY的成本最低（2117美元）。不进行筛查给医疗保健系统带来的成本比每5年筛查一次的成本多4812美元。
不进行筛查导致每个QALY成本增加的原因是T2DM下游并发症的成本。通过确保对未患糖尿病前期的人每3年进行一次IFG筛查，对糖尿病前期患者每年进行一次筛查，加拿大与T2DM相关的健康和经济效益将得到改善。
