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Quasi-experimental evaluation of a nationwide diabetes prevention programme

Abstract

Diabetes is a leading cause of morbidity, mortality and cost of illness1,2. Health behaviours, particularly those related to nutrition and physical activity, play a key role in the development of type 2 diabetes mellitus3. Whereas behaviour change programmes (also known as lifestyle interventions or similar) have been found efficacious in controlled clinical trials4,5, there remains controversy about whether targeting health behaviours at the individual level is an effective preventive strategy for type 2 diabetes mellitus6 and doubt among clinicians that lifestyle advice and counselling provided in the routine health system can achieve improvements in health7,8,9. Here we show that being referred to the largest behaviour change programme for prediabetes globally (the English Diabetes Prevention Programme) is effective in improving key cardiovascular risk factors, including glycated haemoglobin (HbA1c), excess body weight and serum lipid levels. We do so by using a regression discontinuity design10, which uses the eligibility threshold in HbA1c for referral to the behaviour change programme, in electronic health data from about one-fifth of all primary care practices in England. We confirm our main finding, the improvement of HbA1c, using two other quasi-experimental approaches: difference-in-differences analysis exploiting the phased roll-out of the programme and instrumental variable estimation exploiting regional variation in programme coverage. This analysis provides causal, rather than associational, evidence that lifestyle advice and counselling implemented at scale in a national health system can achieve important health improvements.

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Fig. 1: Association between baseline HbA1c and intensive lifestyle counselling and potential confounders.
Fig. 2: Robustness of the effects of being referred to intensive lifestyle counselling on HbA1c and BMI across bandwidth choices.
Fig. 3: Difference-in-differences effect estimates of NHS DPP implementation.

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Data availability

This study used data from the CPRD Aurum and NHS England HES APC database. The data are available from CPRD (https://cprd.com) but restrictions apply to the availability of these data, which were used under license for the current study and so are not publicly available. Owing to CPRD license restrictions, we are unable to share data.

Code availability

All medical codes and algorithms to define variables and R analysis code are available in the Supplementary Information or at the OSF repository (https://osf.io/rqz6x/?view_only=abc4c7a3abcb457596cec9fe2664f542).

References

  1. Lin, X. et al. Global, regional and national burden and trend of diabetes in 195 countries and territories: an analysis from 1990 to 2025. Sci. Rep. 10, 14790 (2020).

    Article  ADS  CAS  PubMed  PubMed Central  Google Scholar 

  2. Bommer, C. et al. The global economic burden of diabetes in adults aged 20–79 years: a cost-of-illness study. Lancet Diabetes Endocrinol. 5, 423–430 (2017).

    Article  PubMed  Google Scholar 

  3. Asif, M. The prevention and control the type-2 diabetes by changing lifestyle and dietary pattern. J. Educ. Health Promot. 3, 1 (2014).

    Article  PubMed  PubMed Central  Google Scholar 

  4. Taheri, S. et al. Effect of intensive lifestyle intervention on bodyweight and glycaemia in early type 2 diabetes (DIADEM-I): an open-label, parallel-group, randomised controlled trial. Lancet Diabetes Endocrinol. 8, 477–489 (2020).

    Article  PubMed  Google Scholar 

  5. Galaviz, K. I. et al. Interventions for reversing prediabetes: a systematic review and meta-analysis. Am. J. Prev. Med. https://doi.org/10.1016/j.amepre.2021.10.020 (2022).

  6. Barry, E., Roberts, S., Finer, S., Vijayaraghavan, S. & Greenhalgh, T. Time to question the NHS diabetes prevention programme. Br. Med. J. https://doi.org/10.1136/bmj.h4717 (2015).

  7. Rubio-Valera, M. et al. Barriers and facilitators for the implementation of primary prevention and health promotion activities in primary care: a synthesis through meta-ethnography. PLoS ONE 9, e89554 (2014).

    Article  ADS  PubMed  PubMed Central  Google Scholar 

  8. Hébert, E. T., Caughy, M. O. & Shuval, K. Primary care providers’ perceptions of physical activity counselling in a clinical setting: a systematic review. Br. J. Sports Med. 46, 625–631 (2012).

    Article  PubMed  Google Scholar 

  9. Dewhurst, A., Peters, S., Devereux-Fitzgerald, A. & Hart, J. Physicians’ views and experiences of discussing weight management within routine clinical consultations: a thematic synthesis. Patient Educ. Couns. 100, 897–908 (2017).

    Article  PubMed  Google Scholar 

  10. Imbens, G. W. & Lemieux, T. Regression discontinuity designs: a guide to practice. J. Econom. 142, 615–635 (2008).

    Article  MathSciNet  MATH  Google Scholar 

  11. Saeedi, P. et al. Global and regional diabetes prevalence estimates for 2019 and projections for 2030 and 2045: results from the International Diabetes Federation Diabetes Atlas, 9th edition. Diabetes Res. Clin. Pract. 157, 107843 (2019).

    Article  PubMed  Google Scholar 

  12. Diabetes Prevention Program Research Group. Long-term effects of lifestyle intervention or metformin on diabetes development and microvascular complications over 15-year follow-up: the Diabetes Prevention Program Outcomes Study. Lancet Diabetes Endocrinol. 3, 866–875 (2015).

    Article  PubMed Central  Google Scholar 

  13. Brink, S. The Diabetes Prevention Program: how the participants did it. Health Aff. 28, 57–62 (2009).

    Article  Google Scholar 

  14. Type 2 Diabetes: Prevention in People at High Risk (NICE, 2012); www.nice.org.uk/guidance/ph38.

  15. Henry, J. A. et al. Lifestyle advice for hypertension or diabetes: trend analysis from 2002 to 2017 in England. Br. J. Gen. Pract. 72, e269–e275 (2022).

    Article  PubMed  PubMed Central  Google Scholar 

  16. Kardakis, T., Jerdén, L., Nyström, M. E., Weinehall, L. & Johansson, H. Implementation of clinical practice guidelines on lifestyle interventions in Swedish primary healthcare—a two-year follow up. BMC Health Serv. Res. 18, 227 (2018).

    Article  PubMed  PubMed Central  Google Scholar 

  17. Milder, I. E., Blokstra, A., de Groot, J., van Dulmen, S. & Bemelmans, W. J. Lifestyle counseling in hypertension-related visits—analysis of video-taped general practice visits. BMC Fam. Pract. 9, 58 (2008).

    Article  PubMed  PubMed Central  Google Scholar 

  18. Sheppard, J. P. et al. Association of guideline and policy changes with incidence of lifestyle advice and treatment for uncomplicated mild hypertension in primary care: a longitudinal cohort study in the Clinical Practice Research Datalink. BMJ Open 8, e021827 (2018).

    Article  PubMed  PubMed Central  Google Scholar 

  19. Lemp, J. M. et al. Use of lifestyle interventions in primary care for individuals with newly diagnosed hypertension, hyperlipidaemia or obesity: a retrospective cohort study. J. R. Soc. Med. 115, 289–299 (2022).

    Article  PubMed  PubMed Central  Google Scholar 

  20. Booth, H. P., Prevost, A. T. & Gulliford, M. C. Access to weight reduction interventions for overweight and obese patients in UK primary care: population-based cohort study. BMJ Open 5, e006642 (2015).

  21. Irving, G. et al. International variations in primary care physician consultation time: a systematic review of 67 countries. BMJ Open 7, e017902 (2017).

    Article  PubMed  PubMed Central  Google Scholar 

  22. Keyworth, C., Epton, T., Goldthorpe, J., Calam, R. & Armitage, C. J. ‘It’s difficult, I think it’s complicated’: Health care professionals’ barriers and enablers to providing opportunistic behaviour change interventions during routine medical consultations. Br. J. Health Psychol. https://doi.org/10.1111/bjhp.12368 (2019).

  23. Kennedy-Martin, T., Curtis, S., Faries, D., Robinson, S. & Johnston, J. A literature review on the representativeness of randomized controlled trial samples and implications for the external validity of trial results. Trials 16, 495 (2015).

    Article  PubMed  PubMed Central  Google Scholar 

  24. Ford, J. G. et al. Barriers to recruiting underrepresented populations to cancer clinical trials: a systematic review. Cancer 112, 228–242 (2008).

    Article  PubMed  Google Scholar 

  25. Rogers, J. R., Liu, C., Hripcsak, G., Cheung, Y. K. & Weng, C. Comparison of clinical characteristics between clinical trial participants and nonparticipants using electronic health record data. JAMA Netw. Open 4, e214732 (2021).

    Article  PubMed  PubMed Central  Google Scholar 

  26. Suvarna, V. Phase IV of drug development. Perspect. Clin. Res. 1, 57–60 (2010).

    PubMed  PubMed Central  Google Scholar 

  27. Hagger, M. S. & Weed, M. DEBATE: do interventions based on behavioral theory work in the real world? Int. J. Behav. Nutr. Phys. Act. 16, 36 (2019).

    Article  PubMed  PubMed Central  Google Scholar 

  28. Marsden, A. M. et al. ‘Finishing the race’—a cohort study of weight and blood glucose change among the first 36,000 patients in a large-scale diabetes prevention programme. Int. J. Behav. Nutr. Phys. Act. 19, 7 (2022).

    Article  PubMed  PubMed Central  Google Scholar 

  29. Cattaneo, M. D., Idrobo, N. & Titiunik, R. A Practical Introduction to Regression Discontinuity Designs (Cambridge Univ. Press, 2019).

  30. Valabhji, J. et al. Early outcomes from the English National Health Service Diabetes Prevention Programme. Diabetes Care 43, 152–160 (2020).

    Article  PubMed  Google Scholar 

  31. Bärnighausen, T. et al. Quasi-experimental study designs series—paper 7: assessing the assumptions. J. Clin. Epidemiol. 89, 53–66 (2017).

    Article  PubMed  Google Scholar 

  32. Selvin, E. et al. Glycated hemoglobin, diabetes and cardiovascular risk in nondiabetic adults. N. Engl. J. Med. 362, 800–811 (2010).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  33. Garg, N. et al. Hemoglobin A1c in nondiabetic patients: an independent predictor of coronary artery disease and its severity. Mayo Clin. Proc. 89, 908–916 (2014).

    Article  CAS  PubMed  Google Scholar 

  34. Lipsitch, M., Tchetgen Tchetgen, E. & Cohen, T. Negative controls: a tool for detecting confounding and bias in observational studies. Epidemiology 21, 383–388 (2010).

    Article  PubMed  PubMed Central  Google Scholar 

  35. Persson, R. et al. CPRD Aurum database: assessment of data quality and completeness of three important comorbidities. Pharmacoepidemiol. Drug Saf. 29, 1456–1464 (2020).

    Article  CAS  PubMed  Google Scholar 

  36. Jonas, D. E. et al. Screening for prediabetes and type 2 diabetes: updated evidence report and systematic review for the US preventive services task force. JAMA 326, 744 (2021).

    Article  PubMed  Google Scholar 

  37. Pronk, N. P. Structured diet and physical activity programmes provide strong evidence of effectiveness for type 2 diabetes prevention and improvement of cardiometabolic health. Evid. Based Med. 21, 18 (2016).

  38. Galaviz, K. I. et al. Global diabetes prevention interventions: a systematic review and network meta-analysis of the real-world impact on incidence, weight and glucose. Diabetes Care 41, 1526–1534 (2018).

    Article  PubMed  PubMed Central  Google Scholar 

  39. Mudaliar, U. et al. Cardiometabolic risk factor changes observed in diabetes prevention programs in US settings: a systematic review and meta-analysis. PLoS Med. 13, e1002095 (2016).

    Article  PubMed  PubMed Central  Google Scholar 

  40. Cardona-Morrell, M., Rychetnik, L., Morrell, S. L., Espinel, P. T. & Bauman, A. Reduction of diabetes risk in routine clinical practice: are physical activity and nutrition interventions feasible and are the outcomes from reference trials replicable? A systematic review and meta-analysis. BMC Public Health 10, 653 (2010).

    Article  PubMed  PubMed Central  Google Scholar 

  41. Diabetes Prevention Programme: Non-Diabetic Hyperglycaemia, January to December 2021. National Diabetes Audit (NHS Digital, 2022); https://digital.nhs.uk/data-and-information/publications/statistical/national-diabetes-audit/dpp-q3-21-22-data.

  42. Whelan, M. & Bell, L. The English National Health Service Diabetes Prevention Programme (NHS DPP): a scoping review of existing evidence. Diabet. Med. 39, e14855 (2022).

    Article  PubMed  PubMed Central  Google Scholar 

  43. Calderón-Larrañaga, S. et al. Unravelling the potential of social prescribing in individual-level type 2 diabetes prevention: a mixed-methods realist evaluation. BMC Med. 21, 91 (2023).

    Article  PubMed  PubMed Central  Google Scholar 

  44. Poupakis, S., Kolotourou, M., MacMillan, H. J. & Chadwick, P. M. Attendance, weight loss and participation in a behavioural diabetes prevention programme. Int. J. Behav. Med. https://doi.org/10.1007/s12529-022-10146-x (2023).

  45. Katzke, V. A., Kaaks, R. & Kühn, T. Lifestyle and cancer risk. Cancer J. 21, 104–110 (2015).

    Article  PubMed  Google Scholar 

  46. Silverio, A. et al. Cardiovascular risk factors and mortality in hospitalized patients with COVID-19: systematic review and meta-analysis of 45 studies and 18,300 patients. BMC Cardiovasc. Disord. 21, 23 (2021).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  47. Hawkes, R. E., Cameron, E., Cotterill, S., Bower, P. & French, D. P. The NHS Diabetes Prevention Programme: an observational study of service delivery and patient experience. BMC Health Serv. Res. 20, 1098 (2020).

    Article  PubMed  PubMed Central  Google Scholar 

  48. Penn, L. et al. NHS Diabetes Prevention Programme in England: formative evaluation of the programme in early phase implementation. BMJ Open 8, e019467 (2018).

    Article  PubMed  PubMed Central  Google Scholar 

  49. Diabetes Prevention Programme. NHS https://gps.northcentrallondon.icb.nhs.uk/service/diabetes-prevention-programme-dpp (2023).

  50. McManus, E., Meacock, R., Parkinson, B. & Sutton, M. Population level impact of the NHS Diabetes Prevention Programme on incidence of type 2 diabetes in England: an observational study. Lancet Reg. Health Eur. 19, 100420 (2022).

    Article  PubMed  PubMed Central  Google Scholar 

  51. National Diabetes Audit. Audit, survey, other reports and statistics. NHS Digital https://digital.nhs.uk/data-and-information/publications/statistical/national-diabetes-audit (2018).

  52. Wolf, A. et al. Data resource profile: Clinical Practice Research Datalink (CPRD) Aurum. Int. J. Epidemiol. 48, 1740–1740g (2019).

    Article  PubMed  PubMed Central  Google Scholar 

  53. Herbert, A., Wijlaars, L., Zylbersztejn, A., Cromwell, D. & Hardelid, P. Data resource profile: Hospital Episode Statistics Admitted Patient Care (HES APC). Int. J. Epidemiol. 46, 1093–1093i (2017).

    Article  PubMed  PubMed Central  Google Scholar 

  54. Sammon, C. J., Leahy, T. P. & Ramagopalan, S. Nonindependence of patient data in the clinical practice research datalink: a case study in atrial fibrillation patients. J. Comp. Eff. Res. 9, 395–403 (2020).

    Article  PubMed  Google Scholar 

  55. Hernán, M. A. Methods of public health research—strengthening causal inference from observational data. N. Engl. J. Med. 385, 1345–1348 (2021).

    Article  PubMed  Google Scholar 

  56. Hernán, M. A. & Robins, J. M. Using big data to emulate a target trial when a randomized trial is not available. Am. J. Epidemiol. 183, 758–764 (2016).

    Article  PubMed  PubMed Central  Google Scholar 

  57. Non-Diabetic Hyperglycaemia, 2019-20 (NHS Digital, 2021); https://files.digital.nhs.uk/31/C59C4B/NDA_NDH_MainReport_2019-20_V1.pdf.

  58. Davidson, J. Clinical codelist—HES—Major Adverse Cardiovascular Event. London School of Hygiene & Tropical Medicine https://doi.org/10.17037/DATA.00002198 (2021).

  59. Imbens, G. & Kalyanaraman, K. Optimal bandwidth choice for the regression discontinuity estimator. Rev. Econ. Stud. 79, 933–959 (2012).

    Article  MathSciNet  MATH  Google Scholar 

  60. Calonico, S., Cattaneo, M. D. & Titiunik, R. Robust nonparametric vonfidence intervals for regression-discontinuity designs: robust nonparametric confidence intervals. Econometrica 82, 2295–2326 (2014).

    Article  MathSciNet  MATH  Google Scholar 

  61. Calonico, S., Cattaneo, M. D., Farrell, M. H. & Titiunik, R. Regression discontinuity designs using covariates. Rev. Econ. Stat. 101, 442–451 (2019).

    Article  Google Scholar 

  62. R Core Team. R: A Language and Environment for Statistical Computing (R Foundation for Statistical Computing, 2022).

  63. Calonico, S., Cattaneo, M. D., Farrell, M. H. & Titiunik, R. rdrobust: robust data-driven statistical inference in regression-discontinuity designs. R package v.2.1.0 (2022).

  64. Callaway, B. & Sant’Anna, P. H. C. Difference-in-differences with multiple time periods. J. Econ. 225, 200–230 (2021).

    Article  MathSciNet  MATH  Google Scholar 

  65. Callaway, B. & Sant’Anna, P. did: Difference in Differences. R package v.2.1.2 (2022).

  66. Proposed CCG Configuration and Member Practices Published. NHS England www.england.nhs.uk/2012/05/ccg-configuration/ (2012).

  67. Output Area to Primary Care Organisation to Strategic Health Authority (December 2011) Lookup in England and Wales. ONS Geography Office of National Statistics https://geoportal.statistics.gov.uk/datasets/ons::output-area-to-primary-care-organisation-to-strategic-health-authority-december-2011-lookup-in-england-and-wales-1/about (2018).

  68. Lower Layer Super Output Area (2011) to Clinical Commissioning Group to Local Authority District (April 2021) Lookup in England. ONS Geography Office of National Statistics https://geoportal.statistics.gov.uk/datasets/ons::lower-layer-super-output-area-2011-to-clinical-commissioning-group-to-local-authority-district-april-2021-lookup-in-england-1/about (2021).

  69. Gaure, S. lfe: linear group fixed effects. R package v.2.8-8 (2022).

  70. Ho, D. E., Imai, K., King, G. & Stuart, E. A. MatchIt: nonparametric preprocessing for parametric causal inference. J. Stat. Softw. 42, 1–28 (2011).

  71. Snowden, J. M., Rose, S. & Mortimer, K. M. Implementation of G-computation on a simulated data set: demonstration of a causal inference technique. Am. J. Epidemiol. 173, 731–738 (2011).

    Article  PubMed  PubMed Central  Google Scholar 

  72. Greifer, N. & Stuart, E. A. Choosing the causal estimand for propensity score analysis of observational studies. Preprint at https://doi.org/10.48550/ARXIV.2106.10577 (2021).

  73. Chatton, A. et al. G-computation, propensity score-based methods and targeted maximum likelihood estimator for causal inference with different covariates sets: a comparative simulation study. Sci. Rep. 10, 9219 (2020).

    Article  ADS  CAS  PubMed  PubMed Central  Google Scholar 

  74. Arel-Bundock, V. marginaleffects: marginal effects, marginal means, predictions and contrasts. R package v.0.7.1 (2022).

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Acknowledgements

This study is based on data from the Clinical Practice Research Datalink obtained under license from the UK Medicines and Healthcare products Regulatory Agency. The data are provided by patients and collected by the NHS as part of their care and support. The interpretation and conclusions contained in this study are those of the authors alone. This work was supported by the Alexander von Humboldt Foundation through the Alexander von Humboldt Professorship awarded to T.B. Data storage and computing resources used in this work were supported by the Ministry of Science, Research and the Arts Baden-Wuerttemberg, Germany, German Research Foundation, the state of Baden-Wuerttemberg, Germany and the German Research Foundation grant no. INST 35/1314-1 FUGG. P.G. was supported by the National Institute of Allergy and Infectious Diseases (1DP2AI171011) and the Chan Zuckerberg Biohub investigator award. J.M.L. acknowledges support from the German Academic Scholarship Foundation.

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Contributions

J.M.L., C.B., A.J., J.I.D., S.V. and P.G. conceived of the research. T.B., S.V. and P.G. acquired funding for the research project. J.M.L., M.X. and F.M. curated the data. J.M.L., M.X., C.B. and P.G. designed the statistical analyses with consults from F.M., T.B. and S.V. J.M.L. and M.X. analysed the data. C.B. and P.G. supervised the analysis. J.M.L. and P.G. wrote the paper with edits from C.B., M.X., F.M., A.J., J.I.D., T.B. and S.V. All authors approved the final manuscript.

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Correspondence to Pascal Geldsetzer.

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Extended data figures and tables

Extended Data Fig. 1 Trends in glycated haemoglobin (HbA1c) before, during and after programme roll-out.

Weighted average HbA1c in one-year intervals from April 2015 to March 2020, for (a) wave 1 and (b) wave 2 practices (intervention) compared to wave 3 practices (control). The y-axis does not start from 0, weighting by number of individuals for each practice, by year. The roll-out of the NHS DPP started in June 2016 for wave 1, in April 2017 for wave 2 and in April 2018 for wave 3.

Extended Data Fig. 2 Regional and temporal variation in NHS DPP programme implementation.

(a) Share of patients eligible for NHS DPP derived via official practice eligibility by roll-out wave and (b) share of patients referred to NHS DPP in each of the nine Strategic Health Authorities.

Extended Data Table 1 Sample characteristics
Extended Data Table 2 Placebo tests with baseline characteristics (Balance tests)
Extended Data Table 3 Regression discontinuity results of being eligible for and of being referred to, intensive lifestyle counselling
Extended Data Table 4 Regression discontinuity results with robust bias-corrected confidence intervals of being eligible for and of being referred to, intensive lifestyle counselling
Extended Data Table 5 Negative outcome controls
Extended Data Table 6 Aggregated treatment effect estimates of NHS DPP implementation on HbA1c from difference-in-differences analysis
Extended Data Table 7 Overview of estimated effects of intensive lifestyle counselling on glycemic control

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Lemp, J.M., Bommer, C., Xie, M. et al. Quasi-experimental evaluation of a nationwide diabetes prevention programme. Nature 624, 138–144 (2023). https://doi.org/10.1038/s41586-023-06756-4

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