Even without diabetes or major depressive disorder (MDD), depression is linked to insulin resistance (IR) in obese and overweight individuals according to a study published in the Journal of Psychiatric Research. Family history of type 2 diabetes moderates the relationship.
The researchers recruited 96 overweight or obese individuals between the ages of 25 and 50 with no history of type 1 or type 2 diabetes and no clinical depression diagnosis. However, 5 participants were taking selective serotonin reuptake inhibitors.
The researchers found a significant positive association between depressive symptoms and steady-state plasma glucose (SSPG). Elevated depressive symptoms increased the odds of having IR (OR=4.22, 95% CI=1.15–17.33). Weight did not make a significant difference.
The researchers also found a correlation between elevated SSPG and family histories of type 2 diabetes and MDD. BMI was associated with depressive symptoms in people without family histories (rho=0.26, P =.029). They found no statistically significant relationship between family history of MDD and depressive symptoms in this group. Among other findings, the researchers stated that the results indicated that people with a family history of type 2 diabetes who have depressive symptoms may be susceptible to IR, which may help doctors catch metabolic disease at an early stage.
The researchers note the small sample size, as well as the small relative number of individuals with a family history of MDD as limitations. In addition, not all participants knew their family history. And, as the 17-item Hamilton Depression Rating Scale may not detect subtle differences in mild depressive symptoms, further studies using additional scales would be useful, they noted.
“Identifying populations at risk of IR with depressive symptoms may contribute to targeted therapeutic interventions to reduce IR and aid in the treatment and prevention of depressive disorders,” the researchers conclude. “Future studies that conduct direct mechanistic testing of this hypothesis are warranted.”
Ong SL, Abbasi F, Watson K, Robakis T, Myoraku A, Rasgon N. Family history of diabetes moderates metabolic depression endophenotypes in overweight/obese adults. J Psychiatr Res. 2022;151:583-589. doi:10.1016/j.jpsychires.2022.05.018