Progression to type 2 diabetes, healthcare utilization, and cost among pre-diabetic patients with or without comorbid hypertension

Abstract

Objective:

This study examined progression to type 2 diabetes and compared healthcare utilization and costs among patients with pre-diabetes, with or without comorbid hypertension.

Research design and methods:

This study drew from a large national claims database (2003–2008). Patients were ≥18 years of age with a medical claim or lab value indicating the presence of pre-diabetes. The index date was the first pre-diabetes diagnosis (ICD-9 codes 790.21, 790.22, 790.29) or qualifying lab value of fasting plasma glucose or impaired glucose intolerance. All patients had ≥12-month data pre- and post- index date. Multivariate analysis was conducted to identify risk factors affecting progression to type 2 diabetes, and to estimate the impact of hypertension status and diabetes progression on healthcare utilization and cost.

Results:

144,410 patients met study criteria, with an average follow-up of 802 (SD 344) days. Among participants, 30.7% progressed to diabetes, with a mean 288 (SD 340) days from pre-diabetes identification to diabetes diagnosis. Compared with patients who did not progress, the total adjusted medical costs for patients who developed diabetes increased by $1429 in 1 year, $2451 in 2 years, and $3621 in 3 years (p < 0.001). Patients with concomitant hypertension were significantly more likely to progress to type 2 diabetes, and had higher total medical costs compared to patients without hypertension ($476 higher in 1 year, $949 in 2 years, $1378 in 3 years).

Conclusions:

Patients with pre-diabetes who progressed to type 2 diabetes had higher healthcare utilization and costs compared with patients who did not. The presence of hypertension substantially increased costs and was associated with higher likelihood of diabetes progression. Blood pressure, lifestyle intervention, body mass index, and other factors cannot be examined due to the limitations of the data. Results may not be generalizable to patients with insurance other than commercial or Medicare.

Key words::

• Healthcare costs
• Healthcare utilization
• Hypertension
• Pre-diabetes
• Type 2 diabetes

Transparency

Declaration of funding

This study was funded by Novartis Pharmaceuticals Corporation.

Declaration of financial/other relationships

B.H.F., D.P., L.M.A. and A.E.R. are employees and stockholders of Novartis Pharmaceuticals Corporation. X.S., N.P., and R.S. have disclosed that they have no relevant financial relationships.

CMRO peer reviewers may have received honoraria for their review work. The peer reviewers on this manuscript have disclosed that they have no relevant financial relationships.

Acknowledgements

The authors would like to thank Caitlin Rothermel, MA, MPHc, of MedLitera, for technical assistance with collating comments and styling to journal requirements.

These data were previously presented at the American Diabetes Association, 70th Scientific Session, Orlando, FL, USA, 25–29 June 2010.