Clinical and cost-effectiveness analysis of improved blood pressure control in hypertensive patients with type 2 diabetes mellitus

Abstract

Summary Background and aims Hypertension in people with type 2 diabetes is associated with an increased risk of micro- and macrovascular complications. The hypertension in diabetes studies so far reported, provide both the clinical information on micro- and macrovascular complications, and the information on use of resources associated with treatment and managing complications, thereby allowing the cost-effectiveness of tight blood pressure control in patients with type 2 diabetes to be assessed. The present study was done to assess the cost-effectiveness of tight control of blood pressure in hypertensive diabetic patients, and to calculate the costing, cost analysis and assess the cost-effectiveness of the intended intervention. Incremental cost-effectiveness analysis and incremental cost per event-free year gained within the trial period of these patients was another objective. Materials and methods A total of 200 hypertensive patients with type 2 diabetes undergoing treatment at the Cardiology OPD, BIRDEM and NHN were selected purposively in this cross-sectional study and were interviewed in March 2004 with a preset questionnaire along with scrutinization of guide book records regarding the direct cost (cost of medical advice, investigations, medical and other treatment) and indirect cost (travel cost, cost of productivity loss and accompanying person(s)). Of them 100 were hypertensive patients with type 2 diabetes having uncontrolled blood pressure and ill-managed (BP > 120/80 mmHg) and 100 were hypertensive patients with type 2 diabetes having controlled blood pressure and well-managed (BP ≤ 120/80 mmHg). A comparison was made between these two groups. The degree and extent of complications, treatment outcome, clinical effectiveness, functional level, consumer's out of pocket expense and indirect cost of consumers were calculated. Incremental cost-effectiveness analysis has been calculated for patients (mean age 52 years) with type 2 diabetes. The incremental cost per event-free year gained within the trial period was also calculated. Results Cost analysis in 200 patients showed that the total cost of treatment was US$ 26616.32 (direct cost US$ 17593.12 and indirect cost US$ 9023.2) with an average of US$ 443.60 per patient. On comparing the two groups, the cost of uncontrolled group was found to be higher by US$ 6657.74 than that of controlled group. The incremental cost of intensive management (well-managed group) was US$178 (US$95–US$232) per patient and event-free time gained in the intensive group was 0.55 (0.18–0.92) years and the lifetime gain was 1.19 (0.79–1.81) years. The incremental cost per event-free year gained was US$356 (costs and effects discounted at 6% a year) and US$198 (costs discounted at 6% a year and effects not discounted). Conclusion Intensive blood pressure control in hypertensive patients with type 2 diabetes significantly increased treatment costs but substantially reduced the cost of complications and increased the event-free days. Timely management of patients with diabetic hypertension is both clinically beneficial and cost-effective. It can increase the interval without complications, and the cost-effectiveness ratio compares favorably with many accepted healthcare program. This indicates that comprehensive care can reduce the burden of cardiac events of diabetic patients even in a developing country.