Constipation is a common gastrointestinal condition characterised by unsatisfactory defecation as a result of infrequent stools, difficult stool passage or both. Overall, the average prevalence of constipation globally is estimated to be 16%. It affects approximately 14.3% of the population in Hong Kong. The condition incurs significant costs, with more than £162 million in associated costs in the UK National Health Service from 2017 to 2018. Similar expenses have been reported in Hong Kong and many Western countries. Previous studies have shown that constipation can lead to serious health complications, including paralytic ileus, faecal impaction, bowel obstruction and even premature death. It not only causes patient discomfort and reduces quality of life but also increases treatment costs.

Psychiatric patients, particularly those on psychotropic drugs such as antipsychotics and antidepressants, are more susceptible to constipation, with more than one third of such patients affected in Europe. This high prevalence may be due to the side effects of these drugs, as well as factors such as a sedentary lifestyle, negative symptoms of schizophrenia, a poor mental state, an unhealthy diet and insufficient fiber intake. The physical health of individuals with severe mental illness, including constipation, has become a major concern in recent years. However, the issues are often overlooked and under-researched, making their management a critical aspect of mental health care.

Common treatments for constipation include pharmacological and non-pharmacological interventions. While pharmacological interventions can effectively alleviate symptoms, they are short-term solutions. The long-term use of laxatives can cause serious side effects, such as bloating, allergic reactions, abdominal pain, metabolic disturbances and hepatotoxicity, which far outweigh the therapeutic effects. Alternative non-invasive interventions, such as auriculotherapy and behavioural therapy, have been found to be ineffective. Only one randomised controlled trial (RCT) of abdominal massage therapy in 60 older adults with constipation in Sweden showed decreased constipation severity and increased bowel movement frequency. However, this did not lead to a decrease in laxative intake, and the intervention requires a therapist to perform. These factors may reduce the accessibility and sustainability of the intervention. Therefore, the investigators propose to test a simpler and less expensive intervention to manage constipation in adult psychiatric out-patients. This intervention will incorporate the concept of self-help, acupressure.

Self-help concept: Since the 19th century, self-care has been a crucial element of healthcare systems. It is defined as a deliberate action undertaken by an individual to enhance their health or manage a disease. Florence Nightingale underscored the significance of personal hygiene and environmental factors in health, thereby establishing self-care as a fundamental principle in public health nursing. Orem further developed the notion of self-care, classifying it into three categories: universal self-care requisites, developmental self-care requisites and health-deviation self-care requisites. Barofsky divided self-care activities into four types: regulatory, preventive, reactive and restorative self-care. Both the World Health Organization and Pender accentuated the function of self-care in health enhancement, disease prevention and health restoration. In Orem's self-care model, patients perceived as active contributors to their own care.

Acupressure: Acupressure involves the application of constant pressure using a fingertip, thumb or the palm of the hand to specific acupoints to stimulate the flow of the life force known as 'Qi' in the meridians. In TCM, health problems are deemed to be due to pathogenic changes in Qi and an imbalance of 'Yin' and 'Yang'. Dysfunction of the viscera and bowels is induced by a deficiency or an excess of Qi in the body. Acupressure is based on the meridian theory, namely that Qi flows through the body along certain channels (meridians), which, if blocked, can cause illness. Stimulation at precise locations (acupoints) along these channels by a healthcare provider or the patients themselves can unblock the flow of Qi, relieving pain and restoring health. Acupressure is able to influence autonomic functions, which can affect the functioning of defecation. In addition, some studies have found that acupressure improves the symptoms of constipation in older adults and patients with stroke or with a vegetative status. Acupressure may have the positive effect of improving constipation. However, there have been no trials (RCTs or non-RCTs) assessing this in psychiatric out-patients. Therefore, the investigators propose to test the intervention in psychiatric out-patients.

Inclusion Criteria:

1. Hong Kong Chinese residents
2. Aged 18 or above
3. Meet the Rome III diagnostic criteria for constipation
4. Mentally stable and competent to perform self-care and learn acupressure, as recommended by their attending psychiatrists through letter/email
5. Able to understand the questionnaire and follow instructions for training

Exclusion Criteria:

1. Have an anatomical or physiological disorder of the gastrointestinal tract, such as malrotation, fistula or colonic neuropathy
2. Have a metabolic or endocrine disease
3. Have lead poisoning or vitamin D intoxication
4. Have had previous training in acupressure
5. Have a physical disability involving the upper limbs
6. Have planned surgery during the study period
7. Pregnant
8. receiving other kinds of "Qi" restoration-based treatment
9. Going to change medication or changed recently
10. Not in any other study or interventions that may improve constipation e.g. consulting dietitian, exercise programme etc.