Depressive symptoms predict non-completion of a structured exercise intervention for people with Type 2 diabetes

To quantify the impact of depressive symptoms on completion of exercise-based rehabilitation for Type 2 diabetes management.

Depressive symptoms were assessed using the Center for Epidemiological Studies Depression scale in a prospective cohort of consecutive patients with Type 2 diabetes entering a 6-month hybrid (home- and clinic-based) exercise rehabilitation programme. Attendance at exercise sessions was monitored and programme completion/non-completion was ascertained.

Of the programme participants (n=624, mean age 55.6±10.5 years, 47% male), 26.8% endorsed significant depressive symptoms (depression score ≥16) and 68.1% completed the intervention, attending 54.6±30.0% of supervised exercise sessions. Baseline depressive symptoms (depression scale score ≥16) increased the risk of non-completion [hazard ratio 1.49 (95% CI 1.10-2.03); P = 0.010], and predicted fewer sessions attended (β=-2.1, P= 0.002) in adjusted models. A depression score threshold of ≥10 (48.4% of participants) predicted non-completion [hazard ratio 1.60 (95% CI 1.19-2.17); P= 0.002) with optimum accuracy. Non-completions resulting from lack of interest (18.9 vs. 11.0%; P= 0.026) and medical complications (14.6 vs. 6.6%; P= 0.006) were more common among participants with depression scores ≥10. Greater hazard ratios for depression scores ≥10 were observed in subgroups not currently using insulin [hazard ratio 1.70 (95% CI 1.24-2.33); P= 0.001), or an antidepressant [hazard ratio 1.83 (95% CI 1.32-2.54); P<0.001].

Depressive symptoms were highly prevalent among participants with Type 2 diabetes entering exercise-based rehabilitation, and even mild depressive symptoms posed a significant barrier to completion. Depression screening may help target additional supports to facilitate completion of exercise interventions for people with Type 2 diabetes.