Effects of Insulin in Perceived Mood Symptoms in Patients With Type 2 Diabetes

Inclusion Criteria: * Diagnosed as having type 2 diabetes mellitus, as defined by the World Health Organization * Are being treated with metformin therapy alone, metformin therapy plus once-daily insulin, or metformin plus one or more other oral antihyperglycemic agents at the time of study entry * Female patients not breastfeeding and female patients of childbearing potential must test negative for pregnancy at time of study entry based on a urine pregnancy test and do not intend to become pregnant during the study and agree to use a reliable form of birth control during the study * Hemoglobin A1c greater than or equal to 7.0% and less than or equal to 10% within 3 months prior to visit 1 * Have given informed consent to participate in the study in accordance with local regulations Exclusion Criteria: * Are investigator site personnel directly affiliated with the study, or are immediate family of investigator site personnel directly affiliated with the study. * Have received treatment within the last 30 days with a drug that has not received regulatory approval for any indication at the time of study entry * Have previously been diagnosed with clinical depression or have been treated with a central nervous system stimulant, antidepressant, antipsychotic, or anxiolytic agent within 30 days prior to study entry * Have a known allergy to insulin lispro low mixture, insulin glargine, metformin hydrochloride, or excipients contained in these products * Have known hypersensitivity or contraindication to metformin hydrochloride