Age- and sex-specific analysis of the impact of bipolar disorder in Iran and its provinces: Prevalence, incidence, and disability-adjusted life years: Global burden of disease 2021

Objectives: This study sought to deliver a prevalence, incidence, and Disability-Adjusted Life Years (DALYs) of bipolar disorder in Iran, covering both national and subnational scales. The results were broken down by age group and sex, alongside an analysis of trends in bipolar disorder from 1990 to 2021. The estimates gathered were further compared to global averages to offer deeper insights into the prevalence and impact of bipolar disorder in Iran. Methods: This study analyzed data from the Global Burden of Disease 2021 framework to assess various health metrics. Key indicators such as prevalence, incidence, and Disability-Adjusted Life Years (DALYs) were examined using all-age count estimates and age-standardized rates per 100,000 individuals. The analysis spanned the years 1990 to 2021, with results categorized by sex, age group, and geographic location. Furthermore, percentage changes over this period were calculated. To enhance the reliability of the findings, all reported estimates included a 95 % uncertainty interval. Results: In 1990, the age-standardized prevalence rate of bipolar disorder in Iran was 770.09 per 100,000 individuals [95 % UI: 657 to 902], and by 2021, it slightly increased to 780 per 100,000 [95 % UI: 667 to 915]. The percentage change over the period from 1990 to 2021 was 0.01 %. In 2021, the total number of bipolar disorder cases in Iran was reported at 724,891, with a 95 % uncertainty interval ranging from 614,626 to 848,263. Among these cases, 376,813 were observed in females and 348,077 in males. Notably, individuals aged 10 to 24 accounted for 127,388 of the overall cases, making this age group the most affected. The age-standardized incidence rate (per 100,000) of bipolar disorder was estimated to be 52 [95 % UI: 44 to 61] in 1990 and 53 [95 % UI: 45 to 62] in 2021, reflecting a minimal change of 0.01 % over this period. Similarly, the age-standardized disability-adjusted life years (DALYs) rate (per 100,000) for bipolar disorder was recorded at 164 [95 % UI: 107 to 240] in 1990 and 166 [95 % UI: 109 to 241] in 2021, with an equivalent negligible change of 0.01 % from 1990 to 2021. Discussion: In Iran, the burden of bipolar disorder has been found to exceed global averages, and due to demographic changes, young population, regional stressors this burden has grown significantly over the past three decades. Therefore, it remains crucial to focus increasing access to mental health care by increasing mental health care infrastructure in the country, especially in densely populated areas.