Table 1 Characteristics of included studies
Citation | Country of the study | Aim of the study | Study population characteristics | Study design | Study setting | Sample size/sample size calculation | Sampling technique | Data source | Definition of subthreshold depression | Measures used | Analysis | Confounder variables adjusted | Key observation |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Dirmaier et al. [43] | Germany | To investigate the effect of depression on adherence to medical recommendation (concerning medication adherence and health behavior) and to investigate the effect of depression and adherence to medical recommendation (medication adherence and health behavior) on HbA1c | Type 2 diabetes patients aged 18 years or older; mean age, 65.7 years; female, 48.8% | Longitudinal study | Hospital based in primary care | 866/not specified | Random sampling | DETECT study of 55,518 patients | DSQ score between 5 and 7 indicated subthreshold depression | -Depression Screening Questionnaire (DSQ) -Medication non-adherence: one question -Non-adherence with health behavior: five item questionnaires | Logistic and linear regression | Gender, age, marital status, employment status, education, physical activity, BMI, smoking, drinking, duration of diabetes, and type of diabetes treatment | Subthreshold depression was associated with problems with health behavior whereas it was not associated with medication adherence. |
Shin et al. [44] | USA | To examine whether problem-solving and diabetes self-care behaviors differed by depressive disorder diagnosis | Type 2 diabetes patients aged 18 years or older; mean age, 58 years; female, 59% | Cross-sectional study | Hospital based | 103/not specified | All patients with type 2 diabetes seen in the clinic between 1st Feb 2011 and 30th June 2013. | Primary (data from patients attending Diabetes Center Clinics at John Hopkins) | DSM-IV criteria for minor depression | -PHQ-2 followed by SCID-I/NP -Summary of Diabetes Self-Care Activities (SDSCA) | ANOVA and multiple linear regression | Age, sex, and diabetes duration | Minor depression was not associated with neither the total score nor the subscale score (diet, exercise, blood sugar, foot care, medication) of self-care activities. |