The study involved more than 1,500 ex-soldiers who were receiving help for their PTSD. Participants in the study had moderate to severe symptoms of PTSD as measured on a scale.
None of the veterans had type 2 diabetes at the start of the study period. At the end of the study period, which lasted 12 months, 105 of the participants had developed type 2.
The participants began the study periods with PTSD symptom scores between 50 and 85 on the scale. A strong improvement in PTSD symptom scores was deemed to be a lowering on the scale of 20 points or more.
5.9% of veterans that did not experience a 20-point lowering on the scale went on to develop type 2 diabetes within the study period. The results showed a much lower rate of type 2 diabetes for those who experienced the strong lowering of PTSD symptom scores. Of these, a much lower 2.6% of veterans developed type 2 within the 12-month study period.
The statistics showed that those who experienced a strong lowering in PTSD symptoms were 49% less likely to develop type 2 diabetes.
Jeffrey Scherrer, lead author of the study and researcher at Saint Louis University School of Medicine, said: “Some people consider PTSD a lifelong sentence for poor health, but this study demonstrates this is not the case if PTSD treatment leads to clinically meaningful PTSD symptom reduction or if PTSD symptoms remit spontaneously.
“We hope patients who have not sought treatment would see these results as additional incentive to obtain evidence-based PTSD psychotherapy.”
There are several reasons why suffering from PTSD might increase the risk of type 2 diabetes. The research team said chronic stress can cause elevated blood glucose levels which can also increase the risk of obesity and depression. Those with PTSD may also be more likely to be inactive, smoke and drink heavily.
Dr Scherrer said: “Clearly these behaviours are correlated with a dysfunctional stress response,” Scherrer said. “The pathway to diabetes in patients with PTSD is likely due to many correlated factors.”
The study is published in the JAMA Psychiatry journal.