Midnight salivary cortisol secretion and the use of antidepressants were associated with abdominal obesity in women with type 1 diabetes: a cross sectional study.

Abdominal obesity is a risk factor for cardiovascular disease. The aim was to explore the influence of midnight salivary cortisol (MSC), antidepressants and sex on abdominal obesity in type 1 diabetes (T1D). We controlled for physical inactivity, smoking, depression and alexithymia.

Cross sectional study of 190 T1D patients (86 women/104 men, 18-59 years, diabetes duration 1-55 years), consecutively recruited from one specialist diabetes outpatient clinic. Anthropometrics, blood pressure, saliva and blood samples were collected, supplemented with data from electronic medical records. Depression and alexithymia were assessed by self-report instruments. MSC (nmol/l) was categorised into 3 levels: high MSC: (≥ 6.7) (n = 64); intermediate MSC: ≥ 3.7- < 6.7) (n = 64); low MSC (< 3.7) (n = 62). Abdominal obesity was defined as waist circumference (meters) ≥ 0.88 for women and as ≥ 1.02 for men. Multiple logistic regression analyses (Backward: Wald) were performed. The Hosmer and Lemeshow test for goodness-of-fit and Nagelkerke R² were used to evaluate each multiple logistic regression analysis model.

The prevalence of abdominal obesity was three times higher in the women than in the men (24% versus 8%) (p = 0.002). Antidepressants were used by 10% of the women and by 4% of the men (p = 0.09). The prevalence of high MSC was 1.7 times higher in the women (43% versus 26%); the prevalence of both intermediate MSC (28% versus 38%) and low MSC (29% versus 36%) were lower in the women (p = 0.048). Significant associations with abdominal obesity were for all 190 patients: female sex (adjusted odds ratio (AOR) 3.4 (confidence interval (CI) 1.4-8.2)) and the use of antidepressants (AOR 4.3 (CI 1.2-14.8)); for the 86 women: high MSC (AOR 18.4 (CI 1.9-181)) and use of antidepressants (AOR 12.2 (CI 2.0-73.6)); and for the 104 men: alexithymia (AOR 5.2 (CI 1.1-24.9)).

Clear sex differences were demonstrated with a distinct higher prevalence of abdominal obesity, as well as a distinct higher prevalence of high midnight salivary cortisol in the women with type 1 diabetes. High midnight salivary cortisol secretion and the use of antidepressants were independent risk factors for abdominal obesity in the women.