Medical Costs Associated with Severity of Chronic Kidney Disease in Type 2 Diabetes Mellitus in Singapore.

INTRODUCTION: This was a retrospective cross-sectional study to assess the impact of chronic kidney disease (CKD) and its severity in Type 2 diabetes mellitus (T2DM) on direct medical costs, and the effects of economic burden on CKD related complications in T2DM in Singapore. METHODS: A total of 1,275 T2DM patients were recruited by the diabetes centre at Khoo Teck Puat Hospital from 2011-2014. CKD stages were classified based on improving global outcome (KDIGO) categories, namely the estimated glomerular filtration rate (eGFR) and albuminuria kidney disease. Medical costs were extracted from the hospital administrative database. RESULTS: CKD occurred in 57.3% of patients. The total mean cost ratio for CKD relative to non-CKD was 2.2 (P<0.001). Mean (median) baseline annual unadjusted costs were significantly higher with increasing CKD severity-S$1,523 (S$949), S$2,065 (S$1,198), S$3,502 (S$1,613), and S$5,328 (S$2,556) for low, moderate, high, and very high risk respectively (P<0.001). CKD (P<0.001), age at study entry (P=0.001), Malay ethnicity (P=0.035), duration of diabetes mellitus (DM; P<0.001), use of statins/fibrates (P=0.021), and modified Diabetes Complications Severity Index (DCSI) (P<0.001) were positively associated with mean annual direct medical costs in the univariate analysis. In the fully adjusted model, association with mean annual total costs persisted for CKD, CKD severity and modified DCSI. CONCLUSION: The presence and increased severity of CKD is significantly associated with higher direct medical costs in T2DM patients. Actively preventing the occurrence and progression in DM-induced CKD may significantly reduce healthcare resource consumption and healthcare costs.

Medical costs associated with chronic kidney disease progression in an Asian population with type 2 diabetes mellitus.

AIM: We aim to examine difference in incremental direct medical costs between non-progressive and progressive chronic kidney disease (CKD) in type 2 diabetes mellitus (T2DM) in Singapore. METHODS: This was a prospective study on 676 patients with T2DM attending a diabetes centre in a regional hospital. Annual direct medical costs were extracted from the administrative database. Ordinary least squares regression was used to estimate contribution of CKD progression to annual costs, adjusting for demographics and baseline clinical covariates. RESULTS: Over mean follow-up period of 2.8 ± 0.4 years, 266 (39.3%) had CKD progression. The excess total follow-up medical costs from baseline was S$4243 higher in progressors compared to non-progressors (P = 0.002). The mean cost differential between the two groups increased from S$2799 in Stages G1-G2 to S$11180 in Stage G4. Inpatient cost accounted for 63.4% of total cost of progression. When stratified by glomerular filtration rate stages, the respective total mean annual costs at stages glomerular filtration rate Stages G3a-G3b and G4 were S$3290 (132%; P = 0.001) and S$4416 (135%; P = 0.011) higher post-progression. CONCLUSION: Chronic kidney disease progression in T2DM is associated with high medical costs. The cost of progression is higher with higher severity of CKD stage at baseline and could be largely driven by inpatient admission.

Direct medical cost associated with diabetic retinopathy severity in type 2 diabetes in Singapore.

Diabetic retinopathy (DR) is a leading cause of vision-loss globally among type 2 diabetes (T2DM) patients. Information on the economic burden of DR in Singapore is limited. We aim to identify the total annual direct medical costs of DR at different stages, and to examine factors influencing the costs. Four hundreds and seventy T2DM patients who attended the Diabetes Centre in a secondary hospital in Singapore in 2011-2014 were included. Digital color fundus photographs were assessed for DR in a masked fashion. Retinopathy severity was further categorized into non-proliferative DR (NPDR), including mild, moderate and severe NPDR, and proliferative DR (PDR). Medical costs were assessed using hospital administrative data. DR was diagnosed in 172 (39.5%) patients, including 51 mild, 62 moderate and 18 severe NPDR, and 41 PDR. The median cost in DR [2012.0 (1111.2-4192.3)] was significantly higher than that in non-DR patients [1158.1 (724.1-1838.9)] (p<0.001). The corresponding costs for mild, moderate, severe NPDR and PDR were [1167.1 (895.4-2012.0)], [2212.0 (1215.5-3825.5)], [2717.5 (1444.0-6310.7)], and [3594.8.1 (1978.4-8427.7)], respectively. After adjustment, the corresponding cost ratios for mild, moderate, severe NPDR, and PDR relative to non-DR were 1.1 (p = 0.827), 1.8 (p = 0.003), 2.0 (p = 0.031) and 2.3 (p<0.001), respectively. The other factors affecting the total cost include smoking (ratio = 1.7, p = 0.019), neuropathy (ratio = 1.9, p = 0.001) and chronic kidney disease (CKD) (ratio = 1.4, p = 0.019). The presence and severity of DR was associated with increased direct medical costs in T2DM. Our results suggest that preventing progression of DR may reduce the economic burden of DR.