Impaired mood homeostasis associated with low mood, history of depression

Individuals with low mood or a history of depression appeared to have impaired mood homeostasis, according to a study of two large population samples published in JAMA Psychiatry.

“We propose that a fundamental — yet unexplored — underlying mechanism of depression may lie in some people’s inability to stabilize mood through their choice of everyday activities,” Maxime Taquet, BMBCh, PhD, of the department of psychiatry at University of Oxford, and colleagues wrote. “This idea was inspired by recent large-scale studies showing a robust pattern of associations between mood and choices of activities in the general population, termed the hedonic flexibility principle. According to this principle, people have a higher propensity to engage in mood-increasing activities when their mood is low and to sustain useful but mood-decreasing activities when their mood is high.”

The investigators hypothesized that this principle helps stabilize mood among healthy people via a homeostatic mechanism; however, if this mechanism is weak or absent, it may increase depression risk.

In the current study, Taquet and colleagues aimed to determine whether mood homeostasis could be a therapeutic target by testing the hypothesis that people with vs. without a history of depression and people with low vs. high mean mood exhibited impaired mood homeostasis. They computed the quantitative association between daily activities and mood in two large case-control studies based on the 58sec data set, which consisted of self-enrolled participants from high-income countries, as well as the WHO Study on Global Aging and Adult Health (WHO SAGE), which consisted of nationally representative participants in low- and middle-income countries recruited through cluster sampling. As the main outcome, the researchers used difference in mood homeostasis between 28,212 participants of the 58sec study with high vs. low mean mood and between 30,116 participants of the WHO SAGE study with vs. without a history of depression.

Among the 58,328 total participants, results showed mood homeostasis was significantly lower among those with low (0.63; 95% CI, 0.45-0.79) vs. high (0.96; 95% CI, 0.96-0.98) mean mood, as well as among those with a history of depression (0.03; 95% CI, 0.26 to 0.24) vs. those without one (0.68; 95% CI, 0.55-0.75). Dynamic simulations revealed that lower mood homeostasis was associated with more depressive episodes that lasted longer.

“As a quantitative approach, measuring mood homeostasis may play a role in personalized psychiatry by identifying the patients most likely to benefit from a variety of treatments,” the researchers wrote. “Additional studies are needed to demonstrate a causal link between mood homeostasis and depression. We believe our findings thus open the door to new research avenues that may ultimately help reduce the disease burden of depression.” – by Joe Gramigna

Disclosures: Taquet reports grants from the Royal College of Psychiatrists and the Foulkes Foundation. Please see the study for all other authors’ relevant financial disclosures.