Background: Diabetes predisposes to heart failure (HF). In a prospective cohort of Chinese with type 2 diabetes, we examined 1) clinical factors associated with incident HF, and 2) mortality post-HF, stratified by ejection fraction (EF).
Methods: Between 1 Jun 1993 and 30 Jun 2015, 23348 patients with type 2 diabetes without history of HF were enrolled in the Hong Kong Diabetes Register, and followed for incident HF until 30 Jun 2017. HF subtypes were defined according to EF on echocardiogram: HF with reduced EF (HFrEF), EF <40%; HF with midrange EF (HFmrEF), EF 40-49%; HF with preserved EF (HFpEF), EF >=50%. Multivariate Cox regression was used to identify clinical factors associated with incident HF vs. no HF, by HF subtypes. 1-year and 5-year mortality rates were compared by HF subtypes.
Results: Over a follow-up of 7.1 years from enrolment, 1195 patients developed HF, of whom 611 (51.1%) had an echocardiogram within 2 years of HF episode. Distribution of HF subtypes as follows: HFrEF 24.1%, HFmrEF 15.2%, HFpEF 60.7%. Old age, low GFR, albuminuria and history of coronary artery disease were associated with increased hazards for all HF subtypes. In addition, female sex, high BMI and history of neuropathy were associated with HFpEF, and low HDL cholesterol was associated with HFmrEF. Over a follow-up of 2.1 years post-HF, 760 patients (63.6%) died with a mortality rate of 189.4 per 1000 person-year. 1-year mortality rate was lower in HFpEF group (16.2%) than those with HFmrEF (vs. 26.9%, p=0.034) and HFrEF (vs. 31.3%, p<0.001). At 5 years, mortality rate in HFpEF group (45.6%) remained lower than those with HFmrEF (vs. 63.4%, p=0.008), but similar to HFrEF group (vs. 49.0%, p=0.199).
Conclusions: HFpEF was the predominant HF subtype in Chinese with diabetes. Clinical factors predicting incident HF differed according to subtypes. 1-year mortality was lower in HFpEF group but mortality at 5 years were similar between HFpEF and HFrEF with a trend of higher mortality in HFmrEF group.
A. Luk: None. J. C. Chan: Consultant; Self; Bayer AG, Boehringer Ingelheim International GmbH, MSD Corporation, Sanofi, Other Relationship; Self; Asia Diabetes Foundation, GemVCare, Research Support; Self; Applied Therapeutics, AstraZeneca, Hua Medicine, Lilly Diabetes, Merck KGaA. X. Zhang: None. E. Fung: None. H. Wu: None. E. S. Lau: None. A. Yang: None. E. Chow: Research Support; Self; Medtronic, Speaker’s Bureau; Self; Novartis Pharmaceuticals Corporation, Sanofi-Aventis. A. P. Kong: Advisory Panel; Self; Lilly Diabetes, Speaker’s Bureau; Self; Abbott, AstraZeneca, Bayer Healthcare Pharmaceuticals Inc., Lilly Diabetes, Sanofi, Stock/Shareholder; Self; Aptorum. R. C. Ma: Other Relationship; Self; AstraZeneca, Medtronic, Research Support; Self; AstraZeneca, Bayer Healthcare Pharmaceuticals Inc., Novo Nordisk, Pfizer Inc., Sanofi-Aventis, Tricida, Inc.