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The right light can keep the doctor away

‘Do no harm’

This excellent editorial makes an impassioned appeal for lighting that supports the sleep-wake cycle of patients with all the benefits to health and well-being for all those who spend their lives in the hospital setting. It’s worth noting the various commercial interests in the conflict of interest statement. But the points are still well-made. – Do no harm: the beginning of the age of healthy hospital lighting

James Greenberg, Richard Lang and the team at Cincinnati Children’s Hospital Medical Centre have been putting some of that thinking into practice in their state of the art neonatal intensive care unit- Spectral Lighting: Novel Science Leads to Innovative NICU Design

Light and pain

An estimated 40% of the US population suffer from chronic pain – a shocking statistic. This classic paper reviews the different sensory components of the hospital environment and how they might help us to manage pain- including lighting.

‘Patients were randomly assigned to a bright or dim room in the hospital. Bright rooms were exposed to 46% more natural light than dim rooms. Patients in the bright rooms required 22% less opioid-equivalent analgesic medications which resulted in 21% decrease in medication costs. Bright room patients reported significantly greater decreases in stress and some decreases in pain.’ 

This more recent paper looks at some of the mechanisms involved in the regulation of pain in more detail pointing to a reciprocal relationship between circadian rhythms and pain. It notes some interesting new work on single-coloured light (e.g. green) and offers some fascinating insights into potential mechanisms at the cellular level. You may need to grab a strong coffee but it’s a real eye-opener. – Pain in its Environmental Context: Implications for Designing Environments to Enhance Pain Control

Bright light and dementia

A growing number of papers suggest that bright light therapy can reduce dementia symptoms and cognitive function without side-effects. This study in Taiwan invited Dementia patients to spend one hour in two different lighting conditions (2,500- 2,600 lux v 4,000 – 4,400 lux) every morning between 10 and 11am over a number of weeks. The results were impressive. ‘Neuropsychiatric Inventory scores were reduced by 65% by the 5th and by 78% by the 9th week. At the same time, Mini-Mental State Examination scores increased by 19% and 28% respectively’.

A major limitation is that this study does not elaborate on the spectral distribution of the light source – simply stating ‘full-spectrum light, products developed by the National Yang Ming Chiao Tung University industry-university cooperation) in a special room. The ambient lights were placed on the ceiling within a 45° visual field) – Pilot Study of the Effects of Bright Ambient Therapy on Dementia Symptoms and Cognitive Function

Lighting can also help to improve accuracy. 

It’s sobering to know that one in five medications are administered incorrectly in hospital. This study shows how better lighting can help care teams to read the small print -especially older care staff. They noted significantly fewer errors at 1,000 lux compared to 500 lux, especially when the font size was small – Light for patient safety: Impact of light on reading errors of medication labels

But brighter isn’t always better… 

This fascinating review of the impact of indoor environmental quality in four elderly care homes in China on the health and well-being of the residents confirms that the quality of light in these settings can make a significant difference. It also notes that above a certain illuminance level, satisfaction with the lighting actually goes down and that this relates to seasonal changes too. Another case for controls… – Indoor Environmental Quality of Residential Elderly Care Facilities in Northeast China

And one for the math geeks…

Please join Professor Brian Sutton and a team of young mathematicians and I for a lecture about light and symmetry and to build a quasiperiodic pattern using a single tile on the 27th and 28th of June- the first time this has ever been done! –

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