The Association Between Glucose Abnormalities and Heart Failure in the Population-Based Reykjavı ´k Study INGA S. THRAINSDOTTIR, MD 1 THOR ASPELUND, PHD 2 GUDMUNDUR THORGEIRSSON, MD, PHD 2,3 VILMUNDUR GUDNASON, MD, PHD 2 THORDUR HARDARSON, MD, PHD 3 KLAS MALMBERG, MD, PHD 1 GUNNAR SIGURDSSON, MD, PHD 2,3 LARS RYD´ EN, MD, PHD 1 OBJECTIVE — Diabetes is an independent risk factor for heart failure, whereas the relation between heart failure and abnormal glucose regulation (AGR) needs further evaluation. We studied this combination in the Reykjavı ´k Study. RESEARCH DESIGN AND METHODS — The Reykjavı ´k Study, a population-based cohort study during 1967–1997, recruited 19,381 participants aged 33– 84 years who were followed until 2002. Oral glucose tolerance tests and chest X-rays were obtained from all participants. Cases were defined in accordance with World Health Organization criteria for type 2 diabetes or AGR (impaired glucose tolerance or impaired fasting glucose) and European Society of Cardiology guidelines for heart failure. RESULTS — The overall prevalence of type 2 diabetes and heart failure was 0.5% in men and 0.4% in women, while AGR and heart failure were found in 0.7% of men and 0.6% of women. Among participants with normal glucose regulation, heart failure was diagnosed in 3.2% com- pared with 6.0 and 11.8% among those with AGR and type 2 diabetes, respectively. The prev- alence of type 2 diabetes in the age-group 45– 65 years increased in both sexes during the period (P for trend = 0.007). The odds ratio was 2.8 (95% CI 2.2–3.6) for the association between type 2 diabetes and heart failure and 1.7 (1.4 –2.1) between AGR and heart failure. CONCLUSIONS — There is a strong association between any form of glucometabolic per- turbation and heart failure. Future studies in this field should focus on all types of glucose abnormalities rather than previously diagnosed diabetes only. Diabetes Care 28:612– 616, 2005 T ype 2 diabetes, a disease of increas- ing prevalence, is a risk factor for heart failure (1,2). Poor glucometa- bolic control, as reflected by a high HbA 1c , increases the risk of developing heart failure (3). Diabetic patients are more prone to develop heart failure dur- ing an ischemic event, despite compara- ble size of myocardial injury, and their prognosis is more unfavorable than that in nondiabetic patients (4). The prevalence of heart failure com- bined with diabetes was 10 and 15%, re- spectively, among elderly Italians. Moreover, a higher proportion of patients with than without heart failure developed diabetes over time (5). Although there are reports on the relationship of either dia- betes or impaired glucose tolerance and heart failure (6,7), the association of the total spectrum of glucose abnormalities and heart failure, as well as the prevalence and risk factors for heart failure, has, to our knowledge, not been studied in a large epidemiological study. The Reykjavı ´k Study is a population- based study that included glucose toler- ance tests for almost every participant. The present study reports on the preva- lence of glucose abnormalities and heart failure and their combination in this population. RESEARCH DESIGN AND METHODS — All inhabitants in the Reykjavı ´k metropolitan area at 1 Decem- ber 1966 and born 1907–1935 were in- vited to participate in the study, as previously reported (8). Those who par- ticipated (n = 19,381) were divided into groups according to date and year of birth. They were subsequently attending the study at six time intervals (between 1967 and 1997). Patients aged 50 – 65 years were represented at all occasions, which allowed for a comparison of prev- alence over time. The case subjects in this study were participants with a diagnosis of type 2 diabetes, abnormal glucose reg- ulation (AGR), and/or heart failure at their first visit to the Reykjavı ´k Study, and the prevalence groups were composed as such. The remaining participants served as control subjects, and data from their first visit were used for comparative anal- ysis. Follow-up was until 2002. Atten- dance rate varied between 65 and 77%, declining somewhat over time. Alto- gether, 9,323 men and 10,058 women at- tended at least one visit. Before the first visit, the participants answered a standardized questionnaire regarding a number of health-related fac- tors (8,9). A medical examination was performed that included height, weight, BMI (kg/m 2 ), blood pressure, electrocar- diogram (ECG), and a chest X-ray (car- diomegaly defined as heart size 550 ●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●●● From the 1 Department of Cardiology, Karolinska University Hospital Solna, Stockholm, Sweden; the 2 Ice- landic Heart Association, Reykjavı´k, Iceland; and the 3 Department of Cardiology, Landspı ´talinn University Hospital, Reykjavı ´k, Iceland. Address correspondence and reprint requests to Inga S. Thrainsdottir, Cardiovascular Research Unit, Karolinska University Hospital Solna, 171 76 Stockholm, Sweden. E-mail: inga.thrainsdottir@medks.ki.se. Received for publication 28 June 2004 and accepted in revised form 14 December 2004. Abbreviations: AGR, abnormal glucose regulation; ECG, electrocardiogram; OGTT, oral glucose toler- ance test. A table elsewhere in this issue shows conventional and Syste `me International (SI) units and conversion factors for many substances. © 2005 by the American Diabetes Association. The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked “advertisement” in accordance with 18 U.S.C. Section 1734 solely to indicate this fact. Epidemiology/Health Services/Psychosocial Research O R I G I N A L A R T I C L E 612 DIABETES CARE, VOLUME 28, NUMBER 3, MARCH 2005