Association between intensive glycemic control and mortality in elderly diabetic patients in the primary care: A retrospective cohort study

Published:April 12, 2020DOI:


      • Both high and low HbA1c were associated with higher mortality in elderly diabetics.
      • A 3-fold increase in odd ratio for mortality was noted when the HbA1c was <6.0%.
      • Risk factors for mortality included smoking, low BMI, high LDL, and sulphonylureas.
      • Aggressive glycaemic control should be approached cautiously in the elderly.



      To examine the association between the most recent HbA1c values and the mortality of elderly Type 2 Diabetic (T2DM) patients managed in the public primary care setting and to explore the associating risk factors.


      Retrospective cohort study.


      All T2DM patients aged 65 or above, who attended a public primary care clinic for regular follow up from 01/01/2012 to 31/12/2012 were included. Their follow up status till 31/12/2017 was reviewed. Those who were deceased on or before 31/12/2017 were matched randomly with controls that were alive in the same cohort for comparison.

      Main Outcome Measures

      Patients’ demographics, smoking status, duration of T2DM, biochemical parameters including the most recent HbA1c, lipid profile, renal function test, drug profile, co-morbidities and all-cause mortality were retrieved from Hospital Authority’s CDARS and CMS systems.


      Both high (>8.0%) and low (<6.5%) HbA1c values were associated with increased odd ratio of all-cause mortality among T2DM elderly patients treated in the primary care. There was a 3-fold increase in odd ratio when the HbA1c reading was very low (<6.0%). Associated risk factors for all-cause mortality in elderly T2DM patients included smoker status, lower BMIs, and higher LDL levels and use of sulphonylureas.


      Glycemic target for elderly T2DM patients should be approached cautiously. Over-aggressive treatment may lead to increased mortality among elderly T2DM patients.


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