Risks of type 2 diabetes mellitus and impaired glucose regulation among elderly patients with essential hypertension: a 10-years cohort study

Abstract

To explore the incidence of type 2 diabetes mellitus (T2DM) and impaired glucose regulation (IGR) among elderly patients with and without hypertension during a follow-up period of 10 years. The subjects were elderly patients (> 60 years old) undergoing annual health examinations at our hospital. And the previously diagnosed T2DM and IGR patients were excluded. And the incidence and risk factors were analyzed by Kaplan-Meier method and COX's proportional hazard. Among a total of 1136 subjects, 582 were enrolled. They were divided into essential hypertension group (HT, n = 384) and non-essential hypertension group (NHT, n = 198) (including new-onset 67 subjects). During a 10-year follow-up, the incidence of new-onset diabetes was 27.6% in HT group and 18.7% in NHT group (HR = 1.48; 95%CI: (1.07 - 2.04), P < 0.05). And the incidence density of T2DM were 33.8‰ and 20.6‰ respectively in two groups. There was no difference in the prevalence of IGR among HT and NHT groups and no difference was found in the prevalence of T2DM or IGR among new-onset HT and NHT groups. The independent risk factors of T2DM was dyslipidemia (HR = 1.459; 95%CI: 1.027 - 2.072, P < 0.05) and hypertension (HR = 1.516; 95%CI: 1.039 - 2.212, P < 0.05) based upon the COX's proportional hazard analysis. Dyslipidemia (HR = 1.545; 95%CI: 1.087 - 2.195, P < 0.05) and hypertension (HR = 1.524; 95%CI: 1.044 - 2.224, P < 0.05) were also independent risk factors of abnormal glycometabolism (T2DM and IGR). Kaplan-Meier analysis indicated that the accumulative incidence of DM and abnormal glycometabolism was different between the HT and NHT groups. The DM risk is 1.516 folds higher in elderly patients with HT than in those without. According to multivariate analysis, hypertension and dyslipidemia are independent risk factors of T2DM and abnormal glycometabolism (T2DM and IGR).