Panic Disorder and Chronic Caffeine Use: A Case-control Study

Coffee and mental disorders: How caffeine affects anxiety and depression

Caffeine, the main psychoactive component in coffee, has garnered significant attention for its potential impact on the most prevalent mental health conditions like anxiety and depression. This chapter comprehensively examines the neurobiological effects of caffeine, its influence on anxiety and depression, and relevant clinical studies. Caffeine exerts its psychostimulant effects primarily through antagonizing adenosine receptors, modulating neurotransmitter systems, and influencing intracellular calcium signaling in the brain. Caffeine exhibits dose-dependent effects. While moderate caffeine consumption is safe in healthy adults and may offer benefits for mental health, excessive intake is linked to adverse effects on neurological and psychiatric health and can aggravate symptoms, highlighting the importance of adjusting consumption patterns. High caffeine intake correlates with elevated anxiety levels, especially in individuals predisposed to anxiety disorders. However, the relationship between caffeine consumption and the risk of depression is intricate, with some studies suggesting a potential protective effect of moderate intake, while others find no significant association. Individual variations in caffeine metabolism, sensitivity, and genetic factors considerably impact responses to caffeine. The chapter also explores the therapeutic potential of caffeine as an adjunct treatment and outlines challenges and future research directions in elucidating caffeine's multifaceted role in mental health.

Prevalence of energy drink consumption world-wide: A systematic review and meta-analysis

BACKGROUND AND AIMS

The increasing market for energy drinks (EDs) in recent years, as well as the health risks caused by their consumption, prompt calls to estimate the prevalence of ED use among different countries. This systematic review and meta-analysis aimed to synthesize the prevalence of ED use in different continents and age groups.

METHOD

We searched two databases (i.e. PubMed and PsycInfo) on 31 March 2023 to identify studies reporting the prevalence of ED use. A total of 192 studies (196 distinct samples; n = 1 120 613; 53.37% males) from the United States, Europe, Asia, Oceania and Africa were included in the analysis. A random-effects model was applied to estimate the overall pooled prevalence at several time-periods. Subgroup analyses were performed to provide prevalence based on continent and age group. The quality of articles was assessed using Joana Brigg's Institute (JBI) critical appraisal checklist. Measurements included prevalence of ED use (i.e. life-time, past 12 months, past 30 days, past 7 days and daily use), continent and age group (i.e. children, adolescents, young adults and adults).

RESULTS

The life-time ED use world-wide-pooled prevalence was estimated to be 54.7% [95% confidence interval (CI) = 48.8-60.6; I2  = 99.80], 43.4% (95% CI = 36.1-50.6; I2  = 99.92) in the past 12 months, 32.3% (95% CI = 28.8-35.8; I2  = 99.82) in the past 30 days, 21.6% (95% CI = 18.7-24.5; I2  = 99.95) in the past 7 days and 8.82% (95% CI = 6.3-11.4; I2  = 99.95) daily ED use. Subgroups analyses showed significant differences in ED life-time use within age groups (P = 0.002) and continents (P = 0.035).

CONCLUSIONS

The world-wide prevalence of energy drink use appears to be high, particularly among adolescents and young adults.

Effects of caffeine on anxiety and panic attacks in patients with panic disorder: A systematic review and meta-analysis

BACKGROUND

Caffeine has been purported to have anxiogenic and panicogenic properties, specifically salient in patients with panic disorder (PD). However, compilations of the magnitude of the effect of caffeine on anxiety and panic attacks are lacking and potential dose-response relationships have not been examined.

OBJECTIVES

In the present systematic review and meta-analysis, we aimed to examine the acute effects of placebo-controlled caffeine challenge on occurrence of panic attacks and subjective anxiety in patients with PD and healthy controls (HC), including dose-response relationships.

METHODS

Systematic searches were performed in six databases. We included blinded placebo-controlled studies of acute caffeine challenge on panic attacks and/or subjective anxiety in adult patients with PD.

RESULTS

Of the 1893 identified articles, ten met our inclusion criteria. The 9 studies investigating panic attacks included 237 patients, of which 51.1% had a panic attack following caffeine, but none after placebo. Six of these studies compared 128 patients with 115 healthy controls (HC), finding that patients (53.9%) were more vulnerable than HC (1.7%) for panic attacks following caffeine (log RR: 3.47; 95% CI 2.06-4.87). Six studies investigated subjective anxiety in 121 patients and 111 HC following caffeine, with an overall effect indicating increased sensitivity to the anxiogenic effects of caffeine in the patient group (Hedges' g = 1.02 [95% CI: 0.09-1.96]). The restricted range of caffeine employed [400-750 mg] and few studies (3) not using 480 mg prevented any meaningful analysis of a dose-response relationship.

LIMITATIONS

Of the ten studies included, only 2 reported anxiety data for the placebo condition, precluding a proper meta-analysis comparing anxiogenic effects of caffeine and placebo. The restricted dose range used prevented assessment of dose-response relationships.

CONCLUSIONS

The results confirm that caffeine at doses roughly equivalent to 5 cups of coffee induces panic attacks in a large proportion of PD patients and highly discriminates this population from healthy adults. Caffeine also increases anxiety in PD patients as well as among healthy adults at these doses although the exact relationship between caffeine-induced anxiety and panic attacks remains uncertain. The results suggest that caffeine targets important mechanisms related to the pathophysiology of PD.

IMPLICATIONS

Future studies should employ a wider range of caffeine doses and investigate contributions of biological and psychological mechanisms underlying the anxiogenic and panicogenic effects of caffeine. In the clinic, patients with PD should be informed about the panicogenic and anxiogenic effects of caffeine, with the caveat that little is known regarding smaller doses than 480 mg. Registration. PROSPERO (www.crd.york.ac.uk/prospero) registration number CRD42019120220.