Risk and prevalence of type 2 diabetes mellitus in patients with major mental health disorders

Background: The bi directional association between major mental health disorders (MMHD) and diabetes mellitus (DM) is well established. Presently, there is little information on the risk and prevalence of DM in Nigerians with MMHD. Objective: To determine the risk and prevalence of DM in Nigerians with MMHD. Design: Cross-sectional study Setting: New World Psychiatry Hospital, Ibadan, Nigeria Subjects: Plasma levels of glucose was determined after an overnight fast and at 120 minutes (2-h PG) of a standard 75-g oral glucose tolerance test in 124 patients with MMHD. Thereafter, normoglycaemia, pre-diabetes and diabetes were defined using the American Diabetes Association criteria. Also, the risk of developing DM within 10 years was assessed using the Finnish Diabetes Association DM Risk Assessment Form. Results: Seventy eight (62.9%), 37 (29.8%) and 9 (7.3%) of the patients had normoglycaemia, pre-diabetes and DM respectively. Only 2 patients had high diabetes risk score. There was progressive rise in 2-h PG level as the diabetes risk score increases. The mean 2-h PG was significantly higher in moderate-and-high risk group combined (MHR) compared with the low risk (LR) group. Also, the proportion of patients with pre-diabetes increased progressively from LR through MHR. Conclusion: Dysglycaemia is not a rare occurrence in Nigerians with MMHD and it appears to be more prevalent in them than in the Nigerian general population. Also, high diabetes risk score could be a strong indication for glucose tolerance testing.