Is hyperglycemia associated with anxious-depressive symptoms? An Italian study in primary care setting

Background: Recent researches exploring the relationship between impaired glucidic tolerance, hyperglycemia or frank type II diabetes mellitus and symptoms of anxiety and depression, mostly conducted on in-patients or highly selected samples and on foreign populations, have reported conflicting results. Nevertheless, these medical and mental conditions are often comorbid in clinical practice. Chronic and systemic inflammation could represent the trait d\'union between these conditions. Primary care represents an interesting setting for exploring this comorbidity, given the high prevalence of psychiatric symptoms displayed by patients. The aims of this research was to measure the association between hyperglycemia and symptoms of anxiety and/or depression in out-patients, and to fill the lack of studies on comorbidity between depression and anxiety disorders and medical conditions in Primary Care services. Method: The present was a cross-sectional study. We evaluated all consecutive patients undergoing a GP consultation in a Northern Italy practice. Exclusion criteria: age b40 or N80; use of antidepressants or antipsychotics medication; psychosis (schizophrenia, schizoaffective, bipolar, organic, or tall as psychotic disorder by DSM IV-TR) or major depression; pregnancy; previous stroke or heart attack; type I diabetes mellitus. The psychometric assessment was done by HADS (Hospital Anxiety and Depression Scale). Blood Glucose measurements (BM) in the last 6 months were considered in our analysis. Hyperglycemia cutoff: blood glucose N100 mg/dl. The statistical analysis was performed using STATA with multiple linear regressions. Results: 209 subjects were recruited in our study (84 men and 125 women). Of those, 48 (22.9%) were affected by hyperglycemia: 22 were men and 26 women. Hyperglycemia was related to HADS-D score in the men sample (β = .44, p = .01). No association was found between hyperglycemia and HADS-A, either in men or in women. Conclusion: The presence of hyperglycemia, well-known cardiovascular risk factor, may have a clinical value in predicting the presence of depressive symptoms, especially in men. Further studies should examine whether our results are generalizable to other populations and whether they are applicable to clinical depression. Molecular researches could focus on clarifying the pathophysiological reasons for such association, also exploring reasons for sex differences.