Effects of nonpharmacological therapies on anxiety and cortisol: A meta-analysis

Although pharmacotherapy is considered the standard of care for the treatment of anxiety, a subset of the patients remains resistant or intolerant to iatrogenic adverse effects. Nonpharmacological and nonpsychotherapeutic interventions, sometimes referred to as "complementary treatments," have emerged as possible alternatives in the treatment of anxiety. We conducted a meta-analysis of placebo-controlled studies to assess the efficacy of nonpharmacological therapy on anxiety. In addition, because serum and salivary cortisol levels are elevated during anxiety, we conducted a separate meta-analysis of pre- and posttreatment cortisol levels.

A search was conducted to identify randomized controlled trials published from January 2010 to May 2017 that measured the effects of nonpharmacological therapies on State Trait Anxiety Index (STAI) scores and cortisol levels before and after treatment.

Four studies met the criteria for inclusion. Our meta-analysis reveals that participants receiving nonpharmacological therapy had a statistically significant decrease in STAI scores (d = -.340; 95% confidence interval [CI], -.639, -.041; P = .026), but no statistically significant decrease in cortisol levels (d = -.085; 95% CI, -.396, .226; P = .591) after intervention.

Our meta-analysis data suggest that "complementary" therapies improved the clinical manifestations of anxiety and thus may be useful as adjunctive approaches to drug treatment.