title: Long-term excess risk of heart failure in people with type 1 diabetes: a prospective case-control study.
abstract: BACKGROUND
  Diabetes is an established risk factor for heart failure, but because nearly all heart failure occurs in older individuals, the excess risk and risk factors for heart failure in individuals with type 1 diabetes are not known. We aimed to determine the excess risk of heart failure in individuals with type 1 diabetes overall and by different levels of glycaemic control and albuminuria.
  
  
  METHODS
  In this prospective case-control study, we identified all individuals with type 1 diabetes registered in the Swedish National Diabetes Registry between Jan 1, 1998, and Dec 31, 2011, and five controls randomly selected from the general population for each patient, matched according to age, sex, and county, and compared them with respect to subsequent hospital admissions for heart failure, with hazard ratios calculated with Cox regression.
  
  
  RESULTS
  In a cohort of 33 402 patients (mean age at baseline 35 years [SD 14], 15 058 [45%] women, and mean duration of diabetes 20·1 years [SD 14·5]), over a mean follow-up of 7·9 years, 1062 (3%) patients were admitted to hospital with a diagnosis of heart failure, compared with 1325 (1%) of 166 228 matched controls over 8·3 years, giving a HR 4·69 (95% CI 3·64-6·04), after adjustment for time-updated age, sex, time-updated diabetes duration, birth in Sweden, educational level, and baseline comorbidities. Worse glycaemic control was associated with increased risk of heart failure in a graded fashion, and so was the presence of albuminuria. Risk of heart failure was also increased among those with well controlled diabetes (adjusted HR 2·16 [95% CI 1·55-3·01]) and in those with no albuminuria (3·38 [2·51-4·57]), but not in the subgroup both well-controlled and with normoalbuminuria (1·59 [0·70-3·58]).
  
  
  CONCLUSIONS
  Individuals with type 1 diabetes had a four-times increase in the risk of being admitted to hospital with heart failure compared with population-based controls. Poor glycaemic control and impaired renal function substantially increased the risk of heart failure.
  
  
  BACKGROUND
  The Swedish state, Swedish Society for Physicians, the Health & Medical Care Committee of the Regional Executive Board (Region Vastra Gotaland, Sweden), the Swedish Heart-Lung Foundation, Diabetes Wellness, Novo Nordisk Foundation (PI M Lind), the Swedish Research Council, and the Swedish Council for working life and social research (Epilife).
authors.affiliation: Department of Molecular and Clinical Medicine, University of Gothenburg and Sahlgrenska University Hospital/Östra Hospital, Gothenburg, Sweden. Electronic address: annika.rosengren@gu.se.
authors.forename: Annika
authors.initials: A
authors.lastname: Rosengren
authors.affiliation: Department of Molecular and Clinical Medicine, University of Gothenburg, Gothenburg, Sweden; Department of Medicine, NU-Hospital Group, Trollhättan and Uddevalla, Sweden.
authors.forename: Daniel
authors.initials: D
authors.lastname: Vestberg
authors.affiliation: Centre of Registers in Region Västra Götaland, Gothenburg, Sweden.
authors.forename: Ann-Marie
authors.initials: AM
authors.lastname: Svensson
authors.affiliation: Saint Luke's Mid America Heart Institute and University of Missouri-Kansas City School of Medicine, Kansas City, MO, USA.
authors.forename: Mikhail
authors.initials: M
authors.lastname: Kosiborod
authors.affiliation: Children's Mercy Hospital, University of Missouri-Kansas City School of Medicine, Kansas City, MO, USA; University of Kansas School of Medicine, Kansas City, KS, USA.
authors.forename: Mark
authors.initials: M
authors.lastname: Clements
authors.affiliation: Department of Molecular and Clinical Medicine, University of Gothenburg and Sahlgrenska University Hospital/Östra Hospital, Gothenburg, Sweden.
authors.forename: Araz
authors.initials: A
authors.lastname: Rawshani
authors.affiliation: Statistiska Konsultgruppen, Gothenburg, Sweden.
authors.forename: Aldina
authors.initials: A
authors.lastname: Pivodic
authors.affiliation: Department of Molecular and Clinical Medicine, University of Gothenburg, Gothenburg, Sweden; Centre of Registers in Region Västra Götaland, Gothenburg, Sweden.
authors.forename: Soffia
authors.initials: S
authors.lastname: Gudbjörnsdottir
authors.affiliation: Department of Molecular and Clinical Medicine, University of Gothenburg, Gothenburg, Sweden; Department of Medicine, NU-Hospital Group, Trollhättan and Uddevalla, Sweden.
authors.forename: Marcus
authors.initials: M
authors.lastname: Lind
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D003922:Diabetes Mellitus, Type 1 / Q000150:complications / Q000453:epidemiology*; D005260:Female; D006333:Heart Failure / Q000150:complications / Q000453:epidemiology*; D006801:Humans; D008297:Male; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012042:Registries; D012307:Risk Factors