Dr Raz Gross, lead author of the study published in the May issue of the Journal of General Internal Medicine, found a correlation between PGC and advancing categories of depression severity in a group of more than 200 Hispanics with diabetes.
"This held especially true among patients with moderate-severe depression, where likelihood for PGC was more than three-fold higher compared to patients without depression," he said.
Gross said that although depressive disorders are more prevalent among adults with diabetes than in the general population, the precise relationship between glycemic control and depression is unclear. Indeed, as he found no association between depression and PGC in non-Hispanic diabetics, there may be factors at play that were outside the scope of the study.
According to the statistics from the Centers for Disease Control and Prevention, Hispanics and other minorities are more likely to suffer from diabetes than white Americans. The age-adjusted percentage of Hispanics with the disease is 6.6 percent, compared with 4.6 percent of whites. Previous research has also shown that Hispanics are less likely to have regular sources of medical care, undergo screening, use preventive services, be referred to a specialist or receive appropriate treatment.
"As rates of diabetes, especially among Hispanics, continue to increase, it is important for clinicians caring for patients with diabetes to be aware of the association between depression and PGC," said Gross.
"Our findings suggest that identification and adequate treatment of depression in this understudied, high-risk population of Hispanic primary care patients might have favorable effects on diabetic outcomes."
The glycemic approach was originally developed for diabetes control. The glycaemic index, which ranks the speed at which the body breaks down carbohydrates and converts them into blood glucose, has since captured the attention of mainstream dieters around the world, largely thanks to supermarkets' and manufacturers' marketing efforts.
However, it is impossible to draw conclusions as to a link between glycemic control and depression for non-diabetics from Gross' study.