According to National Comorbidity Replication study data, the prevalence of anxiety disorders in US adults aged 18 and older has been steadily increasing. Last year, the occurrence of anxiety disorders was 19.2% among US adults. An average of about 31.2% of US adults experience one or another anxiety disorder at some point in their lives.

In the US, major depression is the most common mental disorder. According to the National Survey on Drug Use and Health, an average of about 21.1 million adults in the US had experienced at least one of the major depressive disorders. The occurrence of major depressive disorders was highest among individuals aged 18–25.

According to a scientific report by the WHO, the global occurrence of anxiety, stress, and depression has increased drastically by 26% during the first year of COVID-19. Concerns about mental health conditions had increased with the COVID-19 pandemic. Understanding the neurobiology of stress would be helpful in alleviating stress.

The UNODC World Drug Report stated that nearly 276 people used drugs in the previous year, and about 36 million people had been diagnosed with addiction disorders. During the COVID pandemic, there was a rise in the use of cannabis. An average of about 5.5 percent of the population between the ages of 15 and 64 were found to have used it at least once in the previous year.

Globally, about 10% of children and adolescents encounter a mental disorder; however, the majority do not seek care or assistance. Mental conditions, namely childhood epilepsy, anxiety, behavioural disorders, developmental disabilities, and depression, contribute to disability and illness in young people.

As the global population is ageing at a faster pace. More than 21% of the older population suffers from either a mental or a neurological disorder. The most prevalent mental and neurological disorders among the older population are dementia and depression. Nearly 3.8% of the older population is affected by anxiety disorders. The older population is prone to abandonment, financial, verbal, and psychological abuse.

Based on the National Comorbidity Survey Replication, the prevalence of bipolar disorder was estimated at 2.8% of US adults in the previous year. Around 4.4% of US adults were found to have encountered bipolar disorder at some point in their lives.

As per the WHO report, nearly 25 million people were affected by schizophrenia across the globe. The rate of prevalence is 0.50% among adults. Individuals with schizophrenia are not getting mental health care. Nearly 50% of people in mental hospitals receive a schizophrenia diagnosis, and only 30.3% get specialist mental health care. Effective care is required for individuals with schizophrenia.

According to the study conducted in Austria, conduct disorder was the most common behavioural disorder among the children. Nearly 17.5% of children ages 2–8 are suffering from a mental, behavioural, or developmental disorder. The other disorders, such as ADHD, anxiety, and depression, are more typical as children get older.

As per the study by the WHO, in 2019, around 970 million people of the world's population were living with a mental disorder, of which anxiety and depression disorders were the most common. In 2020, the number of individuals suffering from anxiety and depression increased significantly due to the COVID-19 pandemic. This is an appeal to mental health professionals to address this problem.

As per the NIMH report, the occurrence of obsessive-compulsive disorder was estimated to be 1.2% in US adults aged 18 and up. OCD occurrence rates were estimated to be higher among females (1.9%) than males (0.6%). Nearly more than 50% of adults with OCD encounter serious illness.

Based on diagnostic interview data, the occurrence of post-traumatic stress disorder (PTSD) among US adults was 3.8% in the previous year. The lifetime occurrence of PTSD was 6.9%. Among adults, the occurrence of PTSD was higher for women (5.3%) than men (1.9%). Approximately 36.1 percent encountered serious illness, 33.2 percent encountered moderate impairment, and 30.6% encountered mild illness.

The estimated prevalence of psychosomatic disorders in the US is 4.1% to 6.3%. Women are more affected by psychosomatic disorders. Nearly 21 to 16 percent of individuals with acute somatic symptoms are prone to develop chronic somatic illness. In a gynaecological context, chronic pelvic pain is hard to manage. For this illness, GBP 159 million is spent in the UK each year, and USD 882.5 million is spent in the US.

According to a survey, an estimated 202–510 million people meditate around the world. Anxiety, depression, and stress are regarded as the three major health problems. Nearly 64.6% reported having a positive impact through mediation. Meditation improves not only the physical health but also the mental health of an individual. Employee productivity has increased by 125% when 50% of employers provide mindfulness training to their employees.

Every year, around 710,000 deaths occur by suicide. For every death, there are up to 20 suicide attempts. Suicide not only takes away lives but also has certain ripple effects on families, friends, and communities. Suicide is the second leading cause of death, after automobile accidents. Understanding and recognising the causes of suicides will help to prevent them.

The occurrence of seasonal affective disorder is estimated to be 0.5–5 % in the general population. About10–200% of individuals with major depressive disorder and 25% of individuals with bipolar disorder are affected by seasonal affective disorder.

Adolescents who use digital media for more than 3 hours are at higher risk of mental health issues. Around 13% of children aged 12–17 is reported to have depression, and 32% have anxiety. Cyberbullying or online harassment was experienced by approximately 58% of teens in the United States.

The global psychiatric rehabilitation market size is increasing at a CAGR of 3.8% from 2021 to 2030. The market size in 2021 was USD 150 billion and is estimated to reach USD 198.23 billion by 2029. With the COVID-19 pandemic, the cost of psychiatric rehabilitation is increasing rapidly.

The most common health condition prevailing in the US is mental illness. Nearly half of all people will be diagnosed with a mental illness or disorder at some point in their lives. The prevalence of mental illnesses such as major depression, schizophrenia, and bipolar disorder was estimated at 1 in every 25 US lives. The global mental health market, estimated at USD 381.35 billion in 2020, is expected to reach USD 538.37 billion by 2030, increasing at a CAGR of 3.6%.

In mental health and psychology, case studies are crucial for the development of new ideas and hypotheses. The reports are used to analyse the causes, symptoms, treatments, and possible outcomes. This section focuses on case study methodologies and benefits. Detailed Case studies are frequently used to describe people who have rare, unusual, or abnormal conditions. The ability to frame a psychological condition from a case report aids in the development of new clinical inventions and therapeutics.