Testing a syndemics perspective on the effects of multiple adversities on depression and anxiety symptoms in a representative population sample.

Purpose: Considerable empirical evidence indicates that stressful life experiences may have a negative impact on mental health. However, it is unclear how multiple adverse experiences may intersect to influence symptoms of depression and anxiety. Using a syndemics approach to identify potential synergistic effects between major stressors, we aimed to quantify the roles of multiple recent adverse life experiences on depression and anxiety symptoms.

Methods: A population-representative sample of 1090 Australian adults (53% women, M_age 47 years) completed a cross-sectional survey in 2022 that assessed mental health and retrospective reports of nine specific stressful life experiences in the past year.

Results: The most common adverse life experiences in the past year were financial problems (64%), loneliness (63%), or a major health problem (51%). In multivariate logistic regression analyses, financial problems, personal health problems, health problems in a close contact, relationship problems and loneliness were significantly associated with both depression and anxiety symptoms (p < 0.05). There was just one synergistic interaction and one buffering interaction of combined adversities on anxiety, and no synergistic interactions of adverse experiences on depression. The perceived impact of combined adversities was associated with both depression (b = 0.59, p < 0.001) and anxiety (b = 0.48, p < 0.001).

Conclusion: Adversity was strongly associated with depression and anxiety. Inconsistent with a syndemics framework, there were very few synergistic relationships between different types of adversities, suggesting that different adverse experiences may independently influence mental health. The findings indicate important opportunities for early intervention to prevent depression and anxiety during difficult times.