Unmedicated major depressive disorder in women was associated with lower forearm vascular conductance during passive heating compared to non-depressed (P=0.03) and SSRI-treated women (P=0.01).
Observational (n=64)
Does SSRI or SNRI therapy ameliorate blunted reflex cutaneous vasodilation and sweating responses during passive heating in women with major depressive disorder?
Unmedicated women with MDD exhibit blunted reflex thermoregulation during heat stress, an impairment that appears to be ameliorated by SSRI or SNRI pharmacotherapy.
p-value: p=0.03
Major depressive disorder (MDD) is associated with alterations in the mechanistic regulation of body temperature, including altered circadian temperature profiles, reduced sweating, and blunted cutaneous vasodilation. Selective serotonin reuptake inhibitors (SSRIs) and serotonin norepinephrine reuptake inhibitors (SNRIs) may affect vascular function and sweating; however, heat stress thermoregulation in MDD and during SSRI or SNRI therapy has not been measured. The purpose of this study was to measure reflex cutaneous vasodilation and sweating responses during passive heating in women with MDD who were non- or chronically-treated with either SSRI or SNRI monotherapy. Sixteen women (aged 18-36 yrs) with unmedicated MDD, 16 women with SSRI-treated MDD, 16 women with SNRI-treated MDD, and 16 non-depressed women were passively heated using a water-perfused suit to increase core temperature (T c ) by 1.0°C. Forearm blood flow (FBF; venous occlusion plethysmography) was measured at every 0.1°C increase in T c , normalized to mean arterial pressure (MAP), and expressed as forearm vascular conductance (FVC). Skin blood flow (SkBF; laser-Doppler flowmetry) and local sweat rate (LSR; ventilated sweat capsule) were continuously measured. FVC was lower in unmedicated MDD compared to non-depressed (P=0.03) and SSRI-treated (P=0.01). FVC in SNRI-treated was not different from non-depressed (P=0.09) or MDD (P=1.0) but lower than SSRI-treated women (P=0.03). Greater increases in mean body temperature from baseline were required for onset of LSR and SkBF in unmedicated MDD compared to all other groups (all P<0.05). Together, these findings suggest alterations in reflex thermoregulation in unmedicated women with MDD; these effects may be ameliorated by antidepressant pharmacotherapies.
Fisher et al. (2026) conducted an observational in Major depressive disorder (n=64). SSRI or SNRI monotherapy vs. Unmedicated MDD and non-depressed women was evaluated on Forearm vascular conductance (FVC) during passive heating (p=0.03). Unmedicated major depressive disorder in women was associated with lower forearm vascular conductance during passive heating compared to non-depressed (P=0.03) and SSRI-treated women (P=0.01).