Significant improvement in symptoms of posttraumatic stress disorder (PTSD) is associated with a lower risk for type 2 diabetes (T2D), according to study results published in JAMA Psychiatry.
Previous studies have reported that PTSD is associated with increased risk for T2D, most likely because of the high prevalence of obesity, glucose dysregulation, inflammation, depression, and other risk factors. However, there is no information regarding the association between a reduction in PTSD symptoms and T2D risk.
The goal of this study was to explore whether or not a clinically meaningful PTSD symptom reduction affects risk for T2D.
Clinically meaningful improvement in PTSD symptoms was defined as reduction of ≥20 point in PTSD Checklist score during a 12-month period. The primary outcome was incidence of T2D diagnosis during a 2- to 6-year follow-up period.
The retrospective cohort study used medical record data from Veterans Health Affairs patients who attended a PTSD specialty clinic at least twice between 2008 and 2012. Follow-up continued until 2015. A total of 5916 patients had a PTSD Checklist score above the probable PTSD threshold (50 or higher) and a second PTSD Checklist score recorded in the following 12 months (≥8 weeks after the first score). After exclusion, data from 1598 patients (mean age, 42.1±13.4 years; 84.3% men) with PTSD but without T2D were available for analysis.
Older age (hazard ratio [HR], 1.05; 95% CI, 1.04-1.07; P <.001), black race (HR, 1.86; 95% CI, 1.23-2.83; P =.004), and minimally adequate PTSD psychotherapy duration (HR, 1.73; 95% CI, 1.17-2.55; P =.006) were associated with incident T2D.
The incidence rate of T2D was 18.0 per 1000 person-years, with a lower age-adjusted T2D incidence rate among patients with clinically meaningful PTSD score decrease (7.3 per 1000 person-years) compared with those without similar improvement in PTSD symptoms (16.0 per 1000 person-years; P =.005). Significant improvement in PTSD symptoms, compared with less than clinically significant or no improvement in symptom score, was associated with a 49% lower risk for incident T2D (HR, 0.51; 95% CI, 0.26-0.98; P =.04).
The researchers acknowledged several study limitations, including relatively short follow-up time and missing data regarding the types of traumatic events leading to PTSD. Furthermore, the results may be limited to Veterans Health Affairs patients.
“A decrease in [PTSD Checklist] score, whether through treatment or spontaneous improvement, may help mitigate the greater risk of T2D in patients with PTSD,” concluded the researchers. “Patient education regarding potential health benefits of PTSD treatment may [incentivize] psychotherapy use.”
Scherrer JF, Salas J, Norman SB, et al. Association between clinically meaningful posttraumatic stress disorder improvement and risk of type 2 diabetes [published online August 21, 2019]. JAMA Psychiatry. doi:10.1001/jamapsychiatry.2019.2096