Depression, deficits in functional capacity, and impaired glycemic control in urban African Americans with type 2 diabetes.

ABSTRACT

BACKGROUND: Effective depression treatment does not reliably reduce glycosylated hemoglobin (HbA1c) in depressed patients with type 2 diabetes, possibly in part due to deficits in functional capacity, i.e. performance of certain everyday living skills, essential for effective diabetes self-management. We sought to determine a) the magnitude of deficits in functional capacity among urban, African American (AA) patients with type 2 diabetes, and b) whether these deficits were associated with poorer glycemic control. METHODS: At their initial visit to an inner-city diabetes clinic, 172 AA patients with type 2 diabetes were assessed with a variety of instruments, including the Mini International Neuropsychiatric Interview (MINI) and the UCSD Performance Skills Assessment-Brief (UPSA-B). They then entered a comprehensive diabetes management intervention, whose success was indexed by HbA1c levels at up to four reassessments over a one-year period. A mixed-effects model repeated-measures method was used to predict HbA1c. RESULTS: The prevalence of depression was 19%; the mean UPSA-B score was 81 ± 17. After multivariate adjustment, increased HbA1c levels over time were predicted by the presence of major depression (B = .911, p = .002) and decreasing (worse) scores on the UPSA-B (B = -.016, p = .027), respectively. Further adjustment for increasing the dosage of oral or insulin during the treatment eliminated the association between the UPSA score and HbA1c level (B = -.010, p = .115). CONCLUSIONS: Depression, as well as deficits in functional capacity, predicted reduced effectiveness of a diabetes self-management intervention. Future studies will determine whether interventions targeted at both improve glycemic control.