Screening for type 2 diabetes: do screen-detected cases fare better?
Adina L Feldman, Simon J Griffin, Eva Fhärm, Margareta Norberg, Patrik Wennberg, Lars Weinehall, Olov Rolandsson, Adina L Feldman, Simon J Griffin, Eva Fhärm, Margareta Norberg, Patrik Wennberg, Lars Weinehall, Olov Rolandsson
Abstract
Aims/hypothesis: We aimed to investigate whether diabetes cases detected through screening have better health outcomes than clinically detected cases in a population-based cohort of adults who were eligible to be screened for diabetes at 10 year intervals.
Methods: The Västerbotten Intervention Programme is a community- and individual-based public health programme in Västerbotten County, Sweden. Residents are invited to clinical examinations that include screening for diabetes by OGTTs at age 30, 40, 50 and 60 years (individuals eligible for screening, n = 142,037). Between 1992 and 2013, we identified 1024 screen-detected cases and 8642 clinically detected cases of diabetes using registry data. Clinically detected individuals were either prior screening participants (n = 4506) or people who did not participate in screening (non-participants, n = 4136). Study individuals with diabetes were followed from date of detection until end of follow-up, emigration, death or incident cardiovascular disease (CVD), renal disease or retinopathy event, and compared using Cox proportional hazard regression adjusted for calendar time, age at detection, year of detection, sex and socioeconomic status.
Results: The average age at diabetes diagnosis was 4.6 years lower for screen-detected individuals compared with clinically detected individuals. Overall, those who were clinically detected had worse health outcomes than those who were screen-detected (HR for all-cause mortality 2.07 [95% CI 1.63, 2.62]). Compared with screen-detected study individuals, all-cause mortality was higher for clinically detected individuals who were screening non-participants (HR 2.31 [95% CI 1.82, 2.94]) than for those clinically detected who were prior screening participants (HR 1.70 [95% CI 1.32, 2.18]). Estimates followed a similar pattern for CVD, renal disease and retinopathy.
Conclusions/interpretation: Individuals with screen-detected diabetes were diagnosed earlier and appeared to fare better than those who were clinically detected with regard to all-cause mortality, CVD, renal disease and retinopathy. How much of these associations can be explained by earlier treatment because of screening rather than healthy user bias, lead time bias and length time bias warrants further investigation.
Keywords: Diabetes mellitus; Early diagnosis; Epidemiology; Mass screening; Public health.
Conflict of interest statement
Data availabilityData from the Västerbotten Intervention Study may be obtained from the corresponding author on reasonable request; all linked datasets may be obtained separately from the various register holders, as listed in the Methods section.
Duality of interestSJG declares receipt of an honorarium and reimbursement of travel expenses from Eli Lilly associated with membership of an independent data-monitoring committee for a randomised trial of a medication to lower glucose, and receipt of honoraria for speaking at postgraduate educational meetings from Janssen and Astra Zeneca. All other authors declare no duality of interest associated with this manuscript.
Contribution statementALF designed the analysis plan, performed the data analyses, interpreted the results and drafted and critically revised the manuscript. OR conceived the study question, obtained the data, contributed to the analysis plan, interpreted the results and critically revised the manuscript. SJG contributed to the analysis plan, interpreted the results and critically revised the manuscript. LW and MN coordinated the data collection in the Västerbotten Intervention Study, contributed to the analysis plan and critically revised the manuscript. EF and PW contributed to the analysis plan and critically revised the manuscript. All authors have approved the final version of the manuscript. OR is the guarantor of this work.
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References
- International Diabetes Federation (2015) IDF diabetes atlas, 7th edn. Available from . Accessed 31 July 2017
- Simmons RK, Echouffo-Tcheugui JB, et al. Screening for type 2 diabetes and population mortality over 10 years (ADDITION-Cambridge): a cluster-randomised controlled trial. Lancet. 2012;380:1741–1748. doi: 10.1016/S0140-6736(12)61422-6.
- Simmons RK, Griffin SJ, Witte DR, Borch-Johnsen K, Lauritzen T, Sandbæk A (2017) Effect of population screening for type 2 diabetes and cardiovascular risk factors on mortality rate and cardiovascular events: a controlled trial among 1,912,392 Danish adults. Diabetologia DOI 10.1007/s00125-017-4323-2
- Simmons RK, Rahman M, Jakes RW, et al. Effect of population screening for type 2 diabetes on mortality: long-term follow-up of the Ely cohort. Diabetologia. 2011;54:312–319. doi: 10.1007/s00125-010-1949-8.
- Rahman M, Simmons RK, Hennings SH, Wareham NJ, Griffin SJ. How much does screening bring forward the diagnosis of type 2 diabetes and reduce complications? Twelve year follow-up of the Ely cohort. Diabetologia. 2012;55:1651–1659. doi: 10.1007/s00125-011-2441-9.
- Jansson SP, Andersson DK, Svardsudd K. Mortality and cardiovascular disease outcomes among 740 patients with new-onset type 2 diabetes detected by screening or clinically diagnosed in general practice. Diabet Med. 2016;33:324–331. doi: 10.1111/dme.13019.
- Simmons RK, Griffin SJ, Lauritzen T, Sandbæk A (2017) Effect of screening for type 2 diabetes on risk of cardiovascular disease and mortality: a controlled trial among 139,075 individuals diagnosed with diabetes in Denmark between 2001 and 2009. Diabetologia DOI 10.1007/s00125-017-4299-y
- Engelgau MM, Narayan KM, Herman WH. Screening for type 2 diabetes. Diabetes Care. 2000;23:1563–1580. doi: 10.2337/diacare.23.10.1563.
- Huang Y, Cai X, Mai W, Li M, Hu Y. Association between prediabetes and risk of cardiovascular disease and all cause mortality: systematic review and meta-analysis. BMJ. 2016;355:i5953. doi: 10.1136/bmj.i5953.
- Norberg M, Wall S, Boman K, Weinehall L. The Västerbotten Intervention Programme: background, design and implications. Glob Health Action. 2010;3:4643. doi: 10.3402/gha.v3i0.4643.
- Blomstedt Y, Norberg M, Stenlund H, et al. Impact of a combined community and primary care prevention strategy on all-cause and cardiovascular mortality: a cohort analysis based on 1 million person-years of follow-up in Västerbotten County, Sweden, during 1990-2006. BMJ Open. 2015;5:e009651. doi: 10.1136/bmjopen-2015-009651.
- Norberg M, Blomstedt Y, Lonnberg G, et al. Community participation and sustainability – evidence over 25 years in the Västerbotten Intervention Programme. Glob Health Action. 2012;5:1–9.
- Ludvigsson JF, Otterblad-Olausson P, Pettersson BU, Ekbom A. The Swedish personal identity number: possibilities and pitfalls in healthcare and medical research. Eur J Epidemiol. 2009;24:659–667. doi: 10.1007/s10654-009-9350-y.
- Ludvigsson JF, Almqvist C, Bonamy AK, et al. Registers of the Swedish total population and their use in medical research. Eur J Epidemiol. 2016;31:125–136. doi: 10.1007/s10654-016-0117-y.
- World Health Organization and International Diabetes Federation . Definition and diagnosis of diabetes mellitus and intermediate hyperglycaemia: report of a WHO/IDF consultation. Geneva: World Health Organization; 2006.
- Rolandsson O, Norberg M, Nystrom L, et al. How to diagnose and classify diabetes in primary health care: lessons learned from the Diabetes Register in Northern Sweden (DiabNorth) Scand J Prim Health Care. 2012;30:81–87. doi: 10.3109/02813432.2012.675565.
- Gudbjornsdottir S, Cederholm J, Nilsson PM, Eliasson B, Steering Committee of the Swedish National Diabetes Register The National Diabetes Register in Sweden: an implementation of the St. Vincent Declaration for Quality Improvement in Diabetes Care. Diabetes Care. 2003;26:1270–1276. doi: 10.2337/diacare.26.4.1270.
- Swedish National Diabetes Register (NDR). Annual reports 2007–2013. Available from [in Swedish]. Accessed 31 July 2017
- Wallerstedt SM, Wettermark B, Hoffmann M. The first decade with the Swedish prescribed drug register—a systematic review of the output in the scientific literature. Basic Clin Pharmacol Toxicol. 2016;119:464–469. doi: 10.1111/bcpt.12613.
- Swedish National Board of Health and Welfare. The National Patient Register. Available from . Accessed 31 July 2017
- Robles SC, Marrett LD, Clarke EA, Risch HA. An application of capture-recapture methods to the estimation of completeness of cancer registration. J Clin Epidemiol. 1988;41:495–501. doi: 10.1016/0895-4356(88)90052-2.
- Swedish National Board of Health and Welfare. The Cause of Death Register. Available from [in Swedish]. Accessed 31 July 2017
- Waller G, Janlert U, Norberg M, Lundqvist R, Forssen A. Self-rated health and standard risk factors for myocardial infarction: a cohort study. BMJ Open. 2015;5:e006589. doi: 10.1136/bmjopen-2014-006589.
- Herman WH, Ye W, Griffin SJ, et al. Early detection and treatment of type 2 diabetes reduce cardiovascular morbidity and mortality: a simulation of the results of the Anglo-Danish-Dutch Study of Intensive Treatment in People With Screen-Detected Diabetes in Primary Care (ADDITION-Europe) Diabetes Care. 2015;38:1449–1455. doi: 10.2337/dc14-2459.
- Dugue PA, Lynge E, Rebolj M. Mortality of non-participants in cervical screening: register-based cohort study. Int J Cancer. 2014;134:2674–2682. doi: 10.1002/ijc.28586.
- Zelen M, Feinleib M. On theory of screening for chronic diseases. Biometrika. 1969;56:601–614. doi: 10.1093/biomet/56.3.601.
- Spratt JS, Meyer JS, Spratt JA. Rates of growth of human neoplasms: part II. J Surg Oncol. 1996;61:68–83. doi: 10.1002/1096-9098(199601)61:1<68::AID-JSO2930610102>;2-E.
- Duffy SW, Nagtegaal ID, Wallis M, et al. Correcting for lead time and length bias in estimating the effect of screen detection on cancer survival. Am J Epidemiol. 2008;168:98–104. doi: 10.1093/aje/kwn120.
- Maurice A, Evans DG, Shenton A, et al. Screening younger women with a family history of breast cancer—does early detection improve outcome? Eur J Cancer. 2006;42:1385–1390. doi: 10.1016/j.ejca.2006.01.055.
- Li G, Zhang P, Wang J, et al. Cardiovascular mortality, all-cause mortality, and diabetes incidence after lifestyle intervention for people with impaired glucose tolerance in the Da Qing Diabetes Prevention Study: a 23-year follow-up study. Lancet Diabetes Endocrinol. 2014;2:474–480. doi: 10.1016/S2213-8587(14)70057-9.
- World Health Organization (1999) Definition, diagnosis and classification of diabetes mellitus and its complications. Report of a WHO consultation. Part 1: Diagnosis and classification of diabetes mellitus. Geneva: World Health Organization
Source: PubMed