title: The association between sociodemographic and clinical characteristics and poor glycaemic control: a longitudinal cohort study.
abstract: People with diabetes and poor glycaemic control are at higher risk of diabetes-related complications and incur higher healthcare costs. An understanding of the sociodemographic and clinical characteristics associated with poor glycaemic control is needed to overcome the barriers to achieving care goals in this population.
  
  
  
  We used linked administrative and laboratory data to create a provincial cohort of adults with prevalent diabetes, and a measure of HbA1cthat occurred at least 1 year following the date of diagnosis. The primary outcome was poor glycaemic control, defined as at least two consecutive HbA1cmeasurements ≥ 86 mmol/mol (10%), not including the index measurement, spanning a minimum of 90 days. We used multivariable Cox proportional hazards models to evaluate the association between baseline sociodemographic and clinical factors and poor glycaemic control.
  
  
  
  In this population-based cohort of 169 890 people, younger age was significantly associated with sustained poor glycaemic control, with a hazard ratio (HR) of 3.08, 95% CI (2.79-3.39) for age 18-39 years compared with age ≥ 75 years. Longer duration of diabetes, First Nations status, lower neighbourhood income quintile, history of substance abuse, mood disorder, cardiovascular disease, albuminuria and high LDL cholesterol were also associated with poor glycaemic control.
  
  
  
  Although our results may be limited by the observational nature of the study, the large geographically defined sample size, longitudinal design and robust definition of poor glycaemic control are important strengths. These findings demonstrate the complexity associated with poor glycaemic control and indicate a need for tailored interventions.
authors.affiliation: Department of Family Medicine, Cumming School of Medicine, University of Calgary, Calgary, Canada. kamcbrie@ucalgary.ca.|Department of Community Health Sciences, Cumming School of Medicine, University of Calgary, Calgary, Canada. kamcbrie@ucalgary.ca.|O'Brien Institute for Public Health, Cumming School of Medicine, University of Calgary, Calgary, Canada. kamcbrie@ucalgary.ca.
authors.forename: K A
authors.initials: KA
authors.lastname: McBrien
authors.affiliation: Department of Community Health Sciences, Cumming School of Medicine, University of Calgary, Calgary, Canada.|O'Brien Institute for Public Health, Cumming School of Medicine, University of Calgary, Calgary, Canada.|Department of Medicine, Cumming School of Medicine, University of Calgary, Calgary, Canada.|Libin Cardiovascular Institute, Cumming School of Medicine, University of Calgary, Calgary, Canada.
authors.forename: B J
authors.initials: BJ
authors.lastname: Manns
authors.affiliation: Department of Community Health Sciences, Cumming School of Medicine, University of Calgary, Calgary, Canada.|O'Brien Institute for Public Health, Cumming School of Medicine, University of Calgary, Calgary, Canada.|Department of Medicine, Cumming School of Medicine, University of Calgary, Calgary, Canada.|Libin Cardiovascular Institute, Cumming School of Medicine, University of Calgary, Calgary, Canada.
authors.forename: B R
authors.initials: BR
authors.lastname: Hemmelgarn
authors.affiliation: Department of Medicine, Cumming School of Medicine, University of Calgary, Calgary, Canada.
authors.forename: R
authors.initials: R
authors.lastname: Weaver
authors.affiliation: Department of Medicine, Cumming School of Medicine, University of Calgary, Calgary, Canada.|Diabetes, Obesity and Nutrition Strategic Clinical Network, Alberta Health Services, Toronto, Canada.
authors.forename: A L
authors.initials: AL
authors.lastname: Edwards
authors.affiliation: Department of Family and Community Medicine, Faculty of Medicine, University of Toronto, Toronto, Canada.|Women's College Hospital, Toronto, Canada.
authors.forename: N
authors.initials: N
authors.lastname: Ivers
authors.affiliation: O'Brien Institute for Public Health, Cumming School of Medicine, University of Calgary, Calgary, Canada.|Department of Medicine, Cumming School of Medicine, University of Calgary, Calgary, Canada.
authors.forename: D
authors.initials: D
authors.lastname: Rabi
authors.affiliation: Department of Medicine, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada.|Provincial Primary Health Care, Alberta Health Services, Calgary, Canada.
authors.forename: R
authors.initials: R
authors.lastname: Lewanczuk
authors.affiliation: Department of Family Medicine, Cumming School of Medicine, University of Calgary, Calgary, Canada.|Calgary Zone, Alberta Health Services, Calgary, Canada.
authors.forename: T
authors.initials: T
authors.lastname: Braun
authors.affiliation: Department of Family Medicine, Cumming School of Medicine, University of Calgary, Calgary, Canada.|Department of Pathology and Laboratory Medicine, Cumming School of Medicine, University of Calgary, Calgary, Canada.|Calgary Laboratory Services, Calgary, Canada.
authors.forename: C
authors.initials: C
authors.lastname: Naugler
authors.affiliation: Department of Community Health Sciences, Cumming School of Medicine, University of Calgary, Calgary, Canada.|Department of Medicine, Cumming School of Medicine, University of Calgary, Calgary, Canada.
authors.forename: D
authors.initials: D
authors.lastname: Campbell
authors.affiliation: Department of Medicine, Cumming School of Medicine, University of Calgary, Calgary, Canada.
authors.forename: N
authors.initials: N
authors.lastname: Saad
authors.affiliation: Department of Medicine, Cumming School of Medicine, University of Calgary, Calgary, Canada.
authors.forename: M
authors.initials: M
authors.lastname: Tonelli
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001786:Blood Glucose / Q000378:metabolism*; D015331:Cohort Studies; D048909:Diabetes Complications / Q000097:blood* / Q000453:epidemiology*; D003922:Diabetes Mellitus, Type 1 / Q000097:blood / Q000150:complications / Q000453:epidemiology; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000150:complications / Q000453:epidemiology; D005260:Female; D006442:Glycated Hemoglobin / Q000378:metabolism*; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012959:Socioeconomic Factors; D055815:Young Adult
chemical_list: D001786:Blood Glucose; D006442:Glycated Hemoglobin