A randomized, double-blind, placebo-controlled, crossover trial evaluating the effect of intranasal insulin on cognition and mood in individuals with treatment-resistant major depressive disorder.
Level 2 - randomized trial
Randomized, double-blind, placebo-controlled crossover trial
PubMed 28013123 · doi:10.1016/j.jad.2016.12.006
What was done
A randomized, double-blind, placebo-controlled crossover trial evaluated the effects of intranasal insulin on mood and cognition in 35 adults (aged 18–65, mean age 47.09 ± 9.89 years) meeting DSM-IV-TR criteria for a major depressive episode. Participants were randomized to 4 weeks of intranasal insulin 40 IU four times daily (QID, n = 19) or placebo (n = 16) without stratification based on baseline cognitive deficits. Outcomes included change from baseline on the Montgomery-Åsberg Depression Rating Scale (MADRS), the Positive and Negative Affect Schedule (PANAS), a global index of neurocognition, and patient-reported quality of life.
What was found
No between-group differences were observed for: - Change from baseline on total MADRS score (baseline mean 25.98 ± 2.81). - Positive or Negative subscales of the PANAS. - Global index of neurocognition. - Self-reported quality of life outcomes. Exact numerical values for changes, confidence intervals, and p-values were not reported in the abstract.
Why it matters
Targeting cognitive dysfunction is a major objective in depression treatment, but these findings show no evidence of cognitive or mood improvement from short-term intranasal insulin in this population.
Limits
The sample size was small (n = 35). Potential practice effects and carryover effects in the crossover design could not be excluded. Participants were not stratified by baseline cognitive impairment, which may have reduced the ability to detect benefits in cognitively impaired subgroups. The abstract omits detailed numerical results and statistical values.
Cited by
- supports Clinical trials have evaluated intranasal insulin for the treatment of depression and cognitive impairment.