2051 How representative are UK-based trials investigating lifestyle interventions for diabetes mellitus: a systematic review

Abstract

Abstract Background Type 2 Diabetes mellitus (T2DM) is the most common long-term metabolic condition in older people. In the UK, half of all diabetic patients are over 65 and prevalence reaches 10% in over 75s. Lifestyle interventions reduce diabetic complications and can achieve remission, however, there are concerns over the generalisability of these findings to the diabetic population, particularly elderly, complex patients, and those from ethnic minorities. This systematic review quantifies the disparity between diabetes clinical trial cohorts and the UK diabetic population. Method This is a systematic review of UK-based randomised control trials (RCTs) of non-pharmaceutical interventions in adults with T2DM. Data was collected on characteristics of participants included in these studies, including age, sex, ethnicity, socioeconomic status and education of participants. Results Our search strategy identified 5437 results, of which 161 met the criteria for full-text screening. After full-text screening and de-duplication, 80 RCTs were included in our analysis. Of 80 studies, 60% (48/80) reported a mean participant age under 60. Only 40 (50%) reported participant age range; of these the maximum participant age was under 65 in 20% and under 75 in 60%. Where the mean age of participants was over 60, 56% (18/32) restricted participation by comorbidities. Almost all of these precluded anyone with pre-existing CVD (17/18), one third precluded any comorbidities, and 5/18 precluded hypertensive patients. Only 26% of studies reported the ethnicity of participants. These cohorts were not representative of the UK diabetic population, with underrepresentation of Asian ethnic groups in 90% of trials. Conclusions Representation of elderly patients with comorbidities and those belonging to ethnic minority groups is severely limited in UK based T2DM RCTs of lifestyle interventions. Failure to include a representative population in clinical trial cohorts risks guidance that is not generalisable to the UK diabetic population, potentially exacerbating existing health inequities.