Cardiovascular risk prediction in type 2 diabetes before and after widespread screening: a derivation and validation study.

Citation metadata

From: The Lancet(Vol. 397, Issue 10291)
Publisher: Elsevier B.V.
Document Type: Article
Length: 663 words

Document controls

Main content

Abstract :

Summary Background Until recently, most patients with diabetes worldwide have been diagnosed when symptomatic and have high cardiovascular risk, meaning most should be prescribed cardiovascular preventive medications. However, in New Zealand, a world-first national programme led to approximately 90% of eligible adults being screened for diabetes by 2016, up from 50% in 2012, identifying many asymptomatic patients with recent-onset diabetes. We hypothesised that cardiovascular risk prediction equations derived before widespread screening would now significantly overestimate risk in screen-detected patients. Methods New Zealanders aged 30--74 years with type 2 diabetes and without known cardiovascular disease, heart failure, or substantial renal impairment were identified from the 400 000-person PREDICT primary care cohort study between Oct 27, 2004, and Dec 30, 2016, covering the period before and after widespread screening. Sex-specific equations estimating 5-year risk of cardiovascular disease were developed using Cox regression models, with 18 prespecified predictors, including diabetes-related and renal function measures. Equation performance was compared with an equivalent equation derived in the New Zealand Diabetes Cohort Study (NZDCS), which recruited between 2000 and 2006, before widespread screening. Findings 46 652 participants were included in the PREDICT-1° Diabetes subcohort, of whom 4114 experienced first cardiovascular events during follow-up (median 5*2 years, IQR 3*3--7*4). 14 829 (31*8%) were not taking oral hypoglycaemic medications or insulin at baseline. Median 5-year cardiovascular risk estimated by the new equations was 4*0% (IQR 2*3--6*8) in women and 7*1% (4*5--11*2) in men. The older NZDCS equation overestimated median cardiovascular risk by three times in women (median 14*2% [9*7--20*0]) and two times in men (17*1% [4*5--20*0]). Model and discrimination performance measures for PREDICT-1° Diabetse equations were also significantly better than for the NZDCS equation (eg, for women: R.sup.2=32% [95% CI 29--34], Harrell's C=0*73 [0*72--0*74], Royston's D=1*410 [1*330--1*490] vs R.sup.2=24% [21--26], C=0*69 [0*67--0*70], and D=1*147 [1*107--1*187]). Interpretation International treatment guidelines still consider most people with diabetes to be at high cardiovascular risk; however, we show that recent widespread diabetes screening has radically changed the cardiovascular risk profile of people with diabetes in New Zealand. Many of these patients have normal renal function, are not dispensed glucose-lowering medications, and have low cardiovascular risk. These findings have clear international implications as increased diabetes screening is inevitable due to increasing obesity, simpler screening tests, and the introduction of new-generation glucose-lowering medications that prevent cardiovascular events. Cardiovascular risk prediction equations derived from contemporary diabetes populations, with multiple diabetes-related and renal function predictors, will be required to better differentiate between low-risk and high-risk patients in this increasingly heterogeneous population and to inform appropriate non-pharmacological management and cost-effective targeting of expensive new medications. Funding Health Research Council of New Zealand, Heart Foundation of New Zealand, and Healthier Lives National Science Challenge. Author Affiliation: (a) School of Population Health, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand (b) School of Medicine, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand (c) Department of Cardiology, Middlemore Hospital, Auckland, New Zealand (d) Department of Endocrinology, Middlemore Hospital, Auckland, New Zealand (e) Planning, Funding and Outcome Teams, Waitemata District Health Board, Auckland, New Zealand (f) Strategy and Performance Improvement Teams, Auckland District Health Board, Auckland, New Zealand (g) Ministry of Health, Wellington, New Zealand (h) Population Health, Counties Manukau District Health Board, Auckland, New Zealand (i) Department of Medicine, University of Otago, Dunedin, New Zealand (j) Department of Medicine, University of Otago, Wellington, New Zealand * Correspondence to: Prof Rod Jackson, School of Population Health, Faculty of Medical and Health Sciences, University of Auckland, Auckland 1023, New Zealand Byline: Romana Pylypchuk, PhD (a), Sue Wells, PhD (a), Andrew Kerr, MD (a,c), Katrina Poppe, PhD (a), Matire Harwood, PhD (a), Suneela Mehta, MBChB (e), Corina Grey, PhD (f), Billy P Wu, MPH (a), Vanessa Selak, PhD (a), Paul L Drury, MA (g), Wing Cheuk Chan, MBChB (a,h), Brandon Orr-Walker, MBChB (d), Rinki Murphy, PhD (b), Prof Jim Mann, DM (i), Prof Jeremy D Krebs, PhD (j), Jinfeng Zhao, PhD (a), Prof Rod Jackson, PhD [rt.jackson@auckland.ac.nz] (a)

Source Citation

Source Citation   

Gale Document Number: GALE|A664848911