Mental illness takes a toll not only on the mind, but also on the heart

A new study published in the journal BioMedical Engineering points to a link between mental illness and large blood pressure fluctuations, which can lead to cardiovascular disease and organ damage

National University of Singapore researcher Dr Ren Lim and colleagues at Universiti Malaysia said there was clear evidence that mental illness interferes with the body's autonomic functions, including blood pressure, heart rate, body temperature and breathing

"We reviewed 12 studies of people with anxiety, depression and panic disorder and found that regardless of age, psychiatric disorders were significantly associated with larger changes in daytime blood pressure," said Dr.

"We also found that in people with mental illness, their heart rate is not adapted to external stressors

"Contrary to what many people think, a healthy heart doesn't beat like a metronome

Decreased heart rate variability (HRV) is common in people with psychiatric disorders, suggesting that the body has a poor stress response, exacerbating the negative effects of chronic stress

Unlike a person's heart rate -- the number of heartbeats per minute -- which is usually consistent, HRV is more complex and is the time between heartbeats, which should vary based on external stressors

"Our goal is not a constantly changing heart rate, but high heart rate variability

Low HRV occurs when a person's body is in "fight or flight" mode, is prone to stress, and is commonly seen in people with chronic medical conditions, including cardiovascular and mental health issues

While high blood pressure variability (BPV) during the day is not ideal, nighttime systolic blood pressure should drop by 10% - 20% to allow the heart to rest

This decline (less than 10%) may be due to a number of factors, including autonomic dysfunction, poor sleep quality, and disturbances in the circadian rhythm that regulates the sleep-wake cycle

"The takeaway from this research is that we need to pay more attention to the physical impact of mental illness," Dr Lim said

"This is a significant global burden, affecting 11% - 18% (1 billion people) of the global population

The research was carried out by the University of Malaya, University of South Australia, University of Kebangsaan Malaysia and University of Tonku Abdul Rahman

Journal Reference :

1. Nur Husna Shahimi, Renly Lim, Sumaiyah Mat, Choon-Hian Goh, Maw Pin Tan, Einly Lim.