Stress alters our glucose metabolism, sometimes pushing the phenotype towards a more insulin resistant, diabetic, profile. It can be seen in patients with diabetes undergoing surgical care whose insulin requirements or responses are altered as well as the occasional surgical patient found to have elevated blood sugars without being “pre-diabetic.” If acute stress can raise your blood sugar, what are the effects of chronic stress? A group of psychiatrists is reporting now on a similar finding in veterans with a very different type of stress, post-traumatic stress disorder (PTSD).
The researchers viewed medical records of veterans that carried a diagnosis of PTSD and who completed the PTSD Checklist, a civilian version can be found here, on at least two occasions. The test is a self-reported assessment with a score of over 50 correlating with a diagnosis of PTSD. Higher scores are related to higher levels of PTSD [1]. They looked retrospectively at about 1600 veterans, median age 42, predominantly male and Caucasian who initially had a PTSD score higher than 50 and were entered into treatment. They divided the veterans into two groups based upon an improvement in their scores by more or less than 20 points – scores were acting as a proxy of stress. A reduction in a score by more than 20 points was deemed clinically meaningful.
The two groups were well matched differing by about two years in age, the clinically meaningful group was older at 43.6 years of age, and had a slightly higher initial PTSD score by roughly 2 points at 66.1. There were no differences in obesity, hypertension, or elevated cholesterol nor psychiatric comorbidities [2]. The group with a greater reduction in their PTSD scores received more psychotherapy, fewer anti-anxiety and anti-psychotic medications.
Over 2 to six years of follow up, the incidence of Type 2 diabetes was noted. For the entire population, as you might expect, hypertension, obesity, and elevated cholesterol were associated with a higher incidence of diabetes by two to three-fold; older individuals also had a slightly higher incidence rising by a statistically significant but clinically irrelevant 5%. But a clinically significant reduction in PTSD scoring resulted in a 50% reduction in the risk of Type 2 diabetes, as well as an improvement in self-assessed general health. Interestingly, there was no associated reduction in BMI or Hemoglobin A1c.
The researchers are cautious in explaining the findings but suggest reductions in cortisol levels may play a key role. They point out that depression has been linked to cardiometabolic diseases, more specifically, that glycemic control improves in the face of diminished symptoms of depression. They also suggest a role for PTSD-related inflammation as a source of glucose dysfunction.
The study is limited, males, caucausian, limited information on a range of medical details. But if we are considering the big picture, I think there is clear evidence that glucose dysfunction and the unmasking of a diabetic phenotype is accelerated by stress. It is not the only factor, but it is one that some individuals may find easier to control than their diet and exercise. Perhaps the recommendation for a healthful life should include not just those dietary and exercise injunctions but a suggestion to chill out a bit.
[1] PTSD levels range from the normal stress response, acute stress disorder, uncomplicated PTSD, PTSD with comorbidities, and complex PTSD in ascending order.
[2] The list of psychiatric issues is genuinely frightening and should give every citizen pause in considering how we truly thank our veterans, “for their service.” Depression 73%, anxiety 26%, sleep disorders 44%, alcohol abuse or dependence 40%, drug abuse or dependence 28%, and smoking 50%.
Source: Association between clinically meaningful posttraumatic stress disorder improvement and risk of type 2 diabetes JAMA Psychiatry DOI: 10.1001/jamapsychiatry.2019.2096
