In Reply: Dr Schulte-Herbrüggen and colleagues point out that our analysis showing that treated type 2 diabetes is associated with later development of depressive symptoms should take into account that affective diseases, such as recurrent major depressive disorder and bipolar disorder, may remit between episodes and may not be captured by a questionnaire that assesses the presence or absence of depressive symptoms during a 1-week time frame. We agree that the tools typically used to assess symptoms of depression in population-based studies might misclassify an individual with major depressive disorder or bipolar disorder in remission as being nondepressed. It appears that the majority of population-based studies that have examined diabetes as a risk factor for development of depressive symptoms have used symptom-based questionnaires or health care claims data to identify depression.1 We are aware of only 1 study examining the association between diabetes and depression that has used the diagnostic interview to establish a diagnosis of depression.2 The use of questionnaires that quantify depressive symptoms without confirming a clinical diagnosis are a limitation of epidemiological studies that seek to examine the association between diabetes and depression. Future studies that use diagnostic interviews for depression may elucidate these relationships.
Golden SH, Carnethon MR. Depressive Symptoms and Diabetes—Reply. JAMA. 2008;300(18):2115-2116. doi:10.1001/jama.2008.566