HbA1c variability and the development of microalbuminuria in type 2 diabetes: Tsukuba Kawai Diabetes Registry 2

Abstract

Aims/hypothesis The aim of this study was to examine the association between HbA 1c variability and the development of microalbuminuria as defined by an albumin/creatinine ratio ≥3.4 mg/mmol (≥30 mg/g) in at least two of three consecutive urine samples in Japanese patients with type 2 diabetes. Methods HbA 1c level was measured in 812 serially registered normoalbuminuric adults aged 21-79 years with type 2 diabetes. After registration, a 1-year period to establish baseline values for mean HbA 1c and HbA 1c variability (measured as the intrapersonal SD of serially collected HbA 1c ) was decided upon. The association between HbA 1c variability and the development of microalbuminuria was determined by Cox regression analysis after adjustment for other risk factors for microalbuminuria.

Long-term Glycemic Variability and Risk of Adverse Outcomes: A Systematic Review and Meta-analysis

“…Twenty studies in 87,641 participants met the inclusion criteria. Ten studies included participants from Europe (10,11,14,(16)(17)(18)(19)26,29,35,36), eight from Asia (12,13,15,18,20,24,27,28), four from North America (6,18,23, 25), and one from Australasia (18). The number of participants in each study ranged from 234 to 35,891.…”

“…Thirteen studies included 43,620 participants with type 2 diabetes (12,13,(15)(16)(17)(18)(19)(20)23,24,(26)(27)(28)36). These comprised six retrospective cohort studies (13,15,20,23,28,36), five prospective cohort studies (12,16,17,19,26,27), and two post hoc analyses of randomized controlled trials (18,24).…”

“…These comprised six retrospective cohort studies (13,15,20,23,28,36), five prospective cohort studies (12,16,17,19,26,27), and two post hoc analyses of randomized controlled trials (18,24). All studies used secondary care data apart from one of primary and secondary care data (19) and one of solely U.S. primary care data (23).…”

“…In six studies, loss to follow-up was unclear; six studies had ,10% of participants lost to follow-up, whereas one had lost 27.5% to followup (13). All the studies used some form of adjustment for baseline covariates; however, six did not adjust for baseline diabetes medication (15,19,20,23,24,27), and four did not adjust for baseline hypertension medication (13,16,17,20,27). Of the seven studies that did include hypertension medication (12,15,18,23,24,26,28), two adjusted for ACE inhibitor/angiotensin receptor blocker use (23,24).…”

“…First, unlike short-term glycemic variability, longterm glycemic variability may predict complications in both type 1 and type 2 diabetes (6,(10)(11)(12)(13)(14)(15)(21)(22)(23)(24)(25)(26)(27)(28)(29). Second, HbA 1c is routinely recorded in primary care for both types of diabetes, whereas measures of short-term variability are not (30,31).…”