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Effects of a Population-Based Diabetes Management Program in Singapore
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Effects of a Population-Based Diabetes Management Program in Singapore

Woan Shin Tan, BSocSc, MSocSc; Yew Yoong Ding, MBBS, FRCP, MPH; Wu Christine Xia, BS(IT); and Bee Hoon Heng, MBBS, MSc
Patients utilizing Medisave for a diabetes management program in Singapore were more compliant with care processes, but reductions in hospitalization and costs were not sustained.
Overall, we found that patients in the diabetes management program experienced lower odds of all-cause as well as diabetes-related hospitalization and healthcare costs in the first 2 years, but the effects were not sustained in the third year. This supports the findings of systematic reviews that positive effects of disease management programs tend to diminish with longer lengths of followup. 42,43 Firstly, in the initial phases of the program, better professional care could have contributed to the improvements in outcomes but regression to previous clinical practices44,45 could narrow the reductions at 3 years. Secondly, long-standing behavioral change in particpating patients45 necessary for improving self-management metabolic control may not have occurred. The program could have delayed the onset of symptoms requiring hospitalizations in the short-term rather than eliminate complications and their associated healthcare utilization and cost.46 Thirdly, the routine care for control patients could also have improved over time due to practice improvements across the board and thereby narrowing the differences in outcomes.44,47

We found that the policy effects varied across patient subgroups. While we observed positive and significant reductions in hospitalization risk and costs for patients with poor glycemic control, patients who had no complications and well-controlled blood glucose levels at baseline did not appear to have benefited significantly from the policy. Overall, the average policy effect was attenuated by patients with well-controlled diabetes at baseline. Our results support the evidence in literature that diabetes patients with poorly controlled diabetes at baseline benefit more from frequent measurement of glycemic levels, cholesterol levels, and systolic blood pressure levels.13,39 Outcomes could have improved due to adjustments made, because of regular monitoring, to the treatment of patients with uncontrolled risk factors.

However, as a compliance-oriented program, the Medisave for CDMP may have limited impact on patients with well-controlled diabetes in the 3-year follow-up. Future evaluations could incorporate a longer-term tracking of the health outcomes of this group. Greater focus can be placed on strengthening the self-management capabilities of these patients to prevent the development of complications in the longer term.


This research is limited in several scopes. First, because the program was implemented nationwide, we were unable to conduct a randomized trial. Due to nonrandomization, patients who participated in Medisave for CDMP may differ from nonparticipants systematically. Although we have tried to adjust for selection bias using propensity score matching and DiD, we cannot fully exclude the possibility that unmeasured differences between case and control might influence our results.

Secondly, due to the noncaptive healthcare system in Singapore, patients are able to choose providers on an episodic basis. To minimize this bias, we have included only patients who are consistent users of NHG primary care services using the criteria of at least 1 diabetes-related consultation visit at a NHG primary care clinic for T2DM in 2006 and 2007. As national-level data on healthcare resource use is not publicly available, we were only able to measure use and costs incurred in the 3 regional health clusters (JHS, NHG and NUHS). However, consultations and admissions outside of these clusters are not expected to differ systematically between the program and comparator groups.

Lastly, the NHG primary care clinics are one-stop centers providing medical, nursing, allied health, laboratory, and radiology services in a co-located facility. Our results may not apply to program patients seen by solo general practitioners. Nevertheless, our results should be broadly representative since government primary care clinics account for 77% of all Medisave for CDMP attendances.21


The change in policy is a necessary step towards addressing the misalignment in health and economic incentives between acute and outpatient settings. Compliance with the processes of diabetes care improved among participants in a primary care setting. Overall, the policy reduced hospitalization risk and total healthcare cost in the short term, but effects were not sustained by the third year. Our results also suggest that the policy had varying impacts on different patient subgroups. The likelihood of hospitalization and healthcare cost of participants who had well-controlled diabetes were not reduced.


We thank Li Ruijie, MSc, for support in data extraction from the Chronic Disease Management System, National Healthcare Group, Singapore. We also thank the 2 anonymous reviewers for their comments.

Author Affiliations: From Health Services and Outcomes Research Department, National Healthcare Group, Singapore (WST, YYD, BHH); Department of Geriatric Medicine, Tan Tock Seng Hospital, Singapore (YYD); and Medical Affairs, Alexandra Hospital, Singapore (WCX).

Source of Funding: This project was funded by the National Healthcare Group Small Innovative Grant I (NHG-SIG /11002).

Author Disclosures: The authors report no relationship or financial interest with any entity that would pose a conflict of interest with the subject matter of this article.

Authorship Information: Concept and design (WST, YYD, BHH); acquisition of data (WST, WCX); analysis and interpretation of data (WST, YYD); drafting of the manuscript (WST); critical revision of the manuscript for important intellectual content (YYD, WCX, BHH); statistical analysis (WST); obtaining funding (WST); administrative, technical, or logistic support (WST, WCX); and supervision (BHH).

Address correspondence to: Woan Shin TAN, Health Services and Outcomes Research Department, National Healthcare Group, 6 Commonwealth Lane, #04-01/02 GMTI Building, Singapore 149547. E-mail:
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