Diabetic patients with prior specialist care have better glycaemic control than those with prior primary care

Authors

  • Baiju R. Shah MD FRCPC Research Fellow,

    Corresponding author
    1. 1Institute for Clinical Evaluative Sciences, Toronto, ON, Canada
    2. 2Department of Medicine, University of Toronto, Toronto, ON, Canada
    3. 3Clinical Epidemiology and Health Care Research Program, University of Toronto, Toronto, ON, Canada
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  • Janet E. Hux MD SM FRCPC Associate Professor,

    1. 1Institute for Clinical Evaluative Sciences, Toronto, ON, Canada
    2. 2Department of Medicine, University of Toronto, Toronto, ON, Canada
    3. 3Clinical Epidemiology and Health Care Research Program, University of Toronto, Toronto, ON, Canada
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  • Andreas Laupacis MD MSc FRCPC Professor,

    1. 1Institute for Clinical Evaluative Sciences, Toronto, ON, Canada
    2. 2Department of Medicine, University of Toronto, Toronto, ON, Canada
    3. 3Clinical Epidemiology and Health Care Research Program, University of Toronto, Toronto, ON, Canada
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  • Bernard Zinman Mdcm FRCPC Professor,

    1. 2Department of Medicine, University of Toronto, Toronto, ON, Canada
    2. 4Leadership Sinai Centre for Diabetes, Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, ON, Canada
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  • Peter C. Austin PhD Assistant Professor,

    1. 1Institute for Clinical Evaluative Sciences, Toronto, ON, Canada
    2. 5Department of Public Health Sciences, University of Toronto, Toronto, ON, Canada
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  • Carl Van Walraven MD MSc FRCPC Assistant Professor

    1. 1Institute for Clinical Evaluative Sciences, Toronto, ON, Canada
    2. 6Department of Medicine, University of Ottawa, Ottawa, ON, Canada
    3. 7Clinical Epidemiology Program, Ottawa Health Research Institute, Ottawa, ON, Canada
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Dr Baiju Shah
Institute for Clinical Evaluative Sciences
G106–2075 Bayview Avenue
Toronto
ON M4N 3M5
Canada
E-mail: baiju.shah@ices.on.ca

Abstract

Objective  To compare glycaemic control, as reflected in the A1c level, of diabetic  patients  with  primary  care  vs.  with  specialist  care.

Methods  The study used administrative data from eastern Ontario, Canada, and a database containing the results of all A1c tests from this region between 1 September 1999 and 1 September 2000. To avoid referral bias, diabetic patients with an index specialist visit were selected and separated into those with exclusively primary care previously (n = 974) and those with prior specialist care (n = 3533). We compared A1c levels measured within 30 days of the index visit and hence attributable to the prior care. To control for confounding between the groups, both multiple linear regression and propensity score-based matching were used.

Results  After controlling for confounders, patients with prior specialist care had significantly lower A1c levels (P < 0.0001). Other predictors of lower A1c included older age, shorter diabetes duration, rural residence and higher neighbourhood income. In propensity score-matched cohorts, the A1c level was 8.3 ± 2.0% with prior primary care vs. 7.9 ± 1.6% with prior specialist care (P < 0.0001).

Conclusions  Specialist care prior to the index visit was associated with a lower A1c level than prior primary care. This difference would result in reductions in diabetes complications for patients with ongoing specialist care.

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