A cost analysis of intensified vs conventional multifactorial therapy in individuals with type 2 diabetes: a post hoc analysis of the Steno-2 study

Abstract

Aims/hypothesis: Long-term follow-up of the Steno-2 study demonstrated that intensified multifactorial intervention increased median lifespan by 7.9 years and delayed incident cardiovascular disease by a median of 8.1 years compared with conventional multifactorial intervention during 21.2 years of follow-up. In this post hoc analysis of data from the Steno-2 study, we aimed to study the difference in direct medical costs associated with conventional vs intensified treatment.

Methods: In 1993, 160 Danish individuals with type 2 diabetes and microalbuminuria were randomised to conventional or intensified multifactorial target-driven intervention for 7.8 years. Information on direct healthcare costs was retrieved from health registries, and the costs in the two groups of participants were compared by bootstrap t test analysis.

Results: Over 21.2 years of follow-up, there was no difference in total direct medical costs between the intensified treatment group, €12,126,900, and the conventional treatment group, €11,181,700 (p = 0.48). The mean cost per person-year during 1996-2014 was significantly lower in the intensified treatment group (€8725 in the intensive group and €10,091 in the conventional group, p = 0.045). The main driver of this difference was reduced costs associated with inpatient admissions related to cardiovascular disease (p = 0.0024).

Conclusions/interpretation: Over a follow-up period of 21.2 years, we found no difference in total costs and reduced cost per person-year associated with intensified multifactorial treatment for 7.8 years compared with conventional multifactorial treatment. Considering the substantial gain in life-years and health benefits achieved with intensified treatment, we conclude that intensified multifaceted intervention in high-risk individuals with type 2 diabetes seems to be highly feasible when balancing healthcare costs and treatment benefits in a Danish healthcare setting.

Keywords: Health economy; Multifactorial intervention; Organ complications; Type 2 diabetes.

Fig. 1

Yearly mean direct medical costs per individual (in €) in the two original treatment groups, starting at baseline in 1993. Data are the yearly costs for the group divided by the number of individuals in the group in that year. The peak at 4 years is an artefact from the aggregation of data from years 3 and 4 in some individuals. Solid line, intensified therapy group; dashed line, conventional therapy group

Fig. 2

(a) Risk of death in the intensified therapy group (solid line) and in the conventional therapy group (dashed line). The graphs are plotted to start after baseline and are truncated before the end of follow-up because no deaths occurred in those periods, hence the hazard was not calculated. (b) Yearly direct health costs (as in Fig. 1), with data smoothed. Comparing the two graphs shows similar trends (with allowance for minor delay in the cost curve because of the way data were collected). Increasing mortality is followed closely by increased expenditure, reflecting increased morbidity prior to death

Fig. 3

Total direct medical costs for all individuals in each treatment group. Solid line, intensified therapy group; dashed line, conventional therapy group

Fig. 4

Cumulative number of events including myocardial infarction, stroke, amputation, revascularisation, blindness, end-stage renal disease and death. Recurrent events were included. Solid line, intensified therapy group; dashed line, conventional therapy group