EPIDEMIOLOGY AND BURDEN OF DISEASE OF MAJOR DEPRESSIVE DISORDER (MDD) WITH ANHEDONIA IN ASIA PACIFIC
Authors: Herr *Keira Joann , Berk Michael , Huang Wei-Lieh , Kato Tadafumi , Lee Jung Goo , Ng Chong Guan , Wang Zhen , Webb Thomas , Kasahara-Kiritani Mami , Vandervoort Lawrence , Grillo Vince 
Published: February 2025

Abstract

Background
Major depressive disorder (MDD) is a pervasive mental health condition with a substantial global disease burden. Anhedonia is a core symptom of MDD and has been associated with poorer disease prognosis and suboptimal treatment response [1–3], however, the prevalence of anhedonia and its impact on health related quality of life outcomes is not well-understood. There is a paucity of data on the burden of MDD with anhedonia in Asia Pacific (APAC) [4–6], this is potentially due to anhedonia not typically being managed distinctly from MDD [4,5]. This study aims to provide an overview of the prevalence and quality of life of MDD with anhedonia in Asia Pacific (APAC), with focus on Australia, Mainland China, Japan, Malaysia, South Korea, and Taiwan.

Methods
This cross-sectional web-based survey was conducted in April - May 2023 with 38,623 adults (aged 18 or over years without self-reported bipolar disorder or schizophrenia) among the general populations in Australia, Mainland China, Japan, Malaysia, South Korea, and Taiwan. Respondents, having self-reported MDD diagnosis, and Patient Health Questionnaire-9 (PHQ-9[7]) score 10 or over were classified as MDD respondents and were sub-categorized based on Snaith-Hamilton Pleasure Scale (SHAPS [8]) into anhedonia (cut-off score&gt;2) (MDD-ANH) and non-anhedonia (MDD non-ANH) groups.
Bivariate analysis was used to analyze data pertaining to sociodemographic and health-related QoL (HRQoL). To ensure representativeness, the outcomes were age- and gender-weighted using United Nations population estimates of each country/territory [9].

Results
The anhedonia prevalence among MDD in APAC was estimated 52.5%, ranging between 45.1% in Malaysia and 66.9% in Japan among MDD patients. The MDD point prevalence ranged from 3.4% in Japan to 21.9% in Australia (region: 16.1%). Across APAC, MDD-ANH reported worse HRQoL than MDD non-ANH through RAND mental health composite (RAND MHC [10]) (23.79 vs 30.59, p&lt;.0001) and EuroQol-5- dimension index (EQ-5D [11]) (0.67 vs 0.72, p&lt;.0001). MDD-ANH respondents in all countries/territories reported worse RAND MHC (except South Korea) and EQ-5D (except Australia and South Korea) than MDD non-ANH (p&lt;0.05).

Discussion and Conclusion
This is the first large-scale study to quantify ANH prevalence amongst MDD patients in APAC, with 52.5% of patients reporting anhedonia. The point MDD prevalence in APAC was estimated 16.1%, ranging between 3.4% in Japan to 21.9% in Australia, indicating an increase on previous studies [12–18]. MDD participants with anhedonia reported a consistently lower HRQoL. This suggests anhedonia is associated with a greater disease burden and is an area of unmet need warranting targeted evidence based therapeutic considerations.

References
[1]American Psychiatric Association. Diagnostic and statistical manual of mental disorders: DSM-5. 5th ed. Washington, D.C.: American Psychiatric Publishing; 2013.
[2]Lally N, et al. Anti-anhedonic effect of ketamine and its neural correlates in treatment-resistant bipolar depression. Transl Psychiatry 2014;4:e469– e469.
[3]Lambert C, et al. Anhedonia in depression and schizophrenia: A transdiagnostic challenge. CNS Neurosci Ther 2018;24:615–23.
[4]Cao B, et al. Pharmacological interventions targeting anhedonia in patients with major depressive disorder: A systematic review. Prog Neuropsychopharmacol Biol Psychiatry 2019;92:109–17.
[5]Barthel AL, et al. Anhedonia is Central for the Association between Quality of Life, Metacognition, Sleep, and Affective Symptoms in Generalized Anxiety Disorder: A Network Analysis. J Affect Disord 2020;277:1013–21.
[6]Trostheim M, et al. Assessment of Anhedonia in Adults With and Without Mental Illness: A Systematic Review and Meta-analysis. JAMA Netw Open 2020;3:e2013233.
[7]Kroenke K, et al. The PHQ-9. J Gen Intern Med 2001;16:606–13.
[8]Snaith RP, et al. A Scale for the Assessment of Hedonic Tone the Snaith– Hamilton Pleasure Scale. Br J Psychiatry 1995;167:99–103.
[9]United Nations, Department of Economics and Social Affairs, Population Division. World Population Prospects 2022. New York: United Nations; 2022.
[10]Hays RD, et al. The rand 36-item health survey 1.0. Health Econ 1993;2:217–27.
[11]Herdman M, et al. Development and preliminary testing of the new five-level version of EQ-5D (EQ- 5D-5L). Qual Life Res 2011;20:1727–36.
[12]Chiu E. Epidemiology of depression in the Asia Pacific region. Australas Psychiatry Bull R Aust N Z Coll Psychiatr 2004;12 Suppl:S4-10.
[13]Santomauro DF, et al. Global prevalence and burden of depressive and anxiety disorders in 204 countries and territories in 2020 due to the COVID-19 pandemic. The Lancet 2021;398:1700–12.
[14]Fisher JR, et al. Mental health of people in Australia in the first month of COVID-19 restrictions: a national survey. Med J Aust 2020;213:458–64.
[15]Shi L, et al. Prevalence of and Risk Factors Associated With Mental Health Symptoms Among the General Population in China During the Coronavirus Disease 2019 Pandemic. JAMA Netw Open 2020;3:e2014053.
[16]Shukri MIM, et al. Prevalence and factors associated with depression, anxiety and stress in Malaysia during COVID-19 pandemic: A systematic review. PLOS ONE 2023;18:e0288618.
[17]Shin C, et al. Prevalence and Associated Factors of Depression in General Population of Korea: Results from the Korea National Health and Nutrition Examination Survey, 2014. J Korean Med Sci 2017;32:1861–9.
[18]Liu S-I, et al. Validation of Patient Health Questionnaire for depression screening among primary care patients in Taiwan. Compr Psychiatry 2011;52:96–101.