Diabetes complications at presentation and one year by glycated haemoglobin at diagnosis in a multiethnic and diverse socioeconomic population: Results from the south London diabetes study

Background. who's recommendation of hba 1c ≥ 48 mmol/mol (6.5%) as diagnostic for type 2 diabetes mellitus (t2dm) was adopted by three uk london boroughs in may 2012. the south london diabetes (soul-d) study has recruited people with newly diagnosed t2dm since 2008. we compared participants diagnosed before may 2012 with hba 1c < 48 mmol/mol to those with diagnostic hba 1c ≥ 48 mmol/mol. methods. a prospective cohort study of newly diagnosed t2dm participants from 96 primary care practices,comparing demographic and biomedical variables between those with diagnostic hba 1c < 48 mmol/mol or hba 1c ≥ 48 mmol/mol at recruitment and after one year. results. of 1488 participants,22.8% had diagnostic hba 1c < 48 mmol/mol. they were older and more likely to be white (p < 0.05). at recruitment and one year,there were no between-group differences in the prevalence of diabetic complications,except that those diagnosed with hba 1c < 48 mmol/mol had more sensory neuropathy at recruitment (p = 0.039) and,at one year,had new myocardial infarction (p = 0.012) but less microalbuminuria (p = 0.012). conclusions. use of hba 1c ≥ 48 mmol/mol as the sole t2dm diagnostic criterion may miss almost a quarter of those previously diagnosed in south london yet hba 1c < 48 mmol/mol may not exclude clinically important diabetes. © 2015 mohsin azam et al.