HOW INFORMATION ON TIMING OF GLUCOSE AND BLOOD PRESSURE CONTROL AFFECTS PATIENT DECISION-MAKING IN DIABETES: THE ON-TIME STUDY

Purpose:    Major diabetes trials show that the timing of glucose and blood pressure control has important effects on patient outcomes.  Intensive glucose control lowers complication rates only after 10 years of therapy (lag time), and these benefits last an additional 10 years after glucose levels are no longer well-controlled (duration of benefit).  Conversely, intensive blood pressure control lowers complication rates after 3 years, and these benefits persist only while blood pressure is well-controlled. We examined whether providing patients with lag time and duration of benefit information affects their likelihood of starting additional medications for glucose and blood pressure control.

Method:    We recruited adults, aged 40-70 years old, living with co-occurring diabetes (duration <10 years) and hypertension from a primary care practice (n=35).  We conducted semi-structured, in-person interviews.  We presented subjects with 2 hypothetical scenarios in random order, in which they were recommended additional medications by their physicians for glucose and blood pressure control.  Subjects were asked their baseline likelihood of starting an additional medication on a scale of 1 (not at all) to 10 (very), and then they were provided information on lag time and duration of benefit.  Subjects were asked whether their likelihood of starting medications increased, decreased or stayed the same with additional information. 

Result:    Mean age was 59 years, 66% were female, and 89% were African American.  For both glucose and blood pressure control, 60% of patients were very likely (score ≥7) to start an additional medication. When presented with lag time information for intensive glucose control, almost half of subjects reported a decreased likelihood of starting additional medications (46%, n=16).  However, when presented with duration of benefit information, nearly half reported an increased likelihood of starting additional medication (43%, n=15).  In contrast, for blood pressure control, similar proportions reported increased and decreased likelihood for both lag time and duration of benefit information (Table). 

Conclusion:    Differences in lag time and duration of benefit for glucose and blood pressure control in diabetes may have important effects on patient decision-making.  The shorter lag time and duration of benefit of intensive blood pressure control may have small effects on patient decision making.  However, the longer duration of benefit from intensive glucose control may be a strong motivator for patients to start additional diabetes medications.