The effect of insulin on post-exercise hypoglycemia in adults with type 2 diabetes participating in outpatient exercise-based cardiac rehabilitation.

PURPOSE: Few studies have reported on self-monitored blood glucose changes following acute exercise, particularly in patients with type 2 diabetes prescribed oral sulfonylureas and insulin medication. This study sought to determine the magnitude of post-exercise blood glucose changes and incidence of hypoglycemia (blood glucose < 4.0 mmol/L) in relation to medication regimen.

METHODS

A retrospective chart review was conducted in adults with type 2 diabetes attending a 6-month rehabilitation program. Demographics, medications, exercise prescription and patient-reported pre/post-BG values were collected at program initiation. It was hypothesized that patients with type 2 diabetes will experience a post-exercise capillary blood glucose reduction (ΔcapBG), and that incidents of hypoglycemia (< 4.0 mmol/L) will be strongly associated with insulin or oral secretagogue class of medication.

RESULTS

A chart review was conducted (n = 52, 46.2% males, mean age: 62.7 ± 8.3 years, A1c: 7.7 ± 1.6%, body mass index, BMI: 34.4 ± 7.8 kg/m2) in patients with type 2 diabetes (9.0 ± 7.7 years since diagnosis). A greater reduction in BG was related to a greater pre-exercise BG (beta [95% CI]: - 0.46 [- 0.54, - 0.37] mmol, p < 0.0001), independent of BMI and exercise duration. Post-exercise hypoglycemia (< 4.0 mmol) was associated with prescribed insulin use (vs. non-users: 14.5% vs. 3.0%, p < 0.05). Among insulin users, pre-mixed insulin had the highest incidence of hypoglycemia (vs. non-users: 50% vs. 3%, p < 0.0001) and insulin (bolus and basal; vs. non-users: 11.1% vs. 3%, p = 0.04).

CONCLUSIONS

These findings may suggest a low post-exercise hypoglycemia occurrence in patients with type 2 diabetes, except when taking insulin. Self-management strategies should be considered, especially for patients on insulin medications.