Abstract
Diabetes mellitus (DM) and hypertension (HTN) are common risk factors for heart disease in the population. The goal of this study was to evaluate independent association between type 2 DM and HTN using a very large database. We used ICD-9 codes for type 2 DM (250.00, 250.02) and HTN (401.0, 401.1, 401.9) from the Nationwide Inpatient Sample (NIS) database. We randomly selected the years in the database between 1992 and 2002. We used uni- and multi-variate analysis to evaluate any association between type 2 DM and HTN adjusting for co-morbid conditions. The 1992 database contained a total of 6,195,744 patients. Type 2 DM was associated with 37.5% of patients with HTN vs. 11.4% of the control group (odds ratio (OR): 4.63, Confidence interval (CI) 4.61–4.693, p < 0.001). The 2002 database contained a total of 7,853,982 patients. Type 2 DM was associated with 57.2% of patients with HTN vs. 22.9% of the control group (OR: 4.49, CI 4.47–4.52, p < 0.001). Using multivariate analysis adjusting for age, gender, hyperlipidemia, obesity, smoking, and chronic renal failure, type 2 DM remained independently associated with HTN in both years (for the year 1992: OR: 2.49, CI: 2.47–2.51, p < 0.001 and for the year 2002 OR: 2.19, CI: 2.18–2.20, p < 0.001). The same association was persistently found using samples for each year between 1992 and 2002. The presence of type 2 DM is strongly associated with HTN. This association is independent of co-morbid conditions and was persistent with similar odds ratio over a period of 10 years.