Evaluation of the Effects of an Intervention Intended to Optimize the Sleep Environment Among the Elderly: An Exploratory Study

Figures & data

Table 1 Themes and Components of the Brief Intervention on Optimization of the Sleep Environment

Themes	Information Shared	Optimization Proposals
Air quality and odors	The sleep environment is the most polluted place in a home. It contains chemical contaminants, dust mites, fungi and bacteria. Under the sheets, many factors contribute to poor air quality: high level of humidity, high temperature, low volatility, high molecular weight of pollutants, and poor ventilation. Good air quality and adequate ventilation are important to ensure quality sleep.	- Aerate as much as possible - Vacuum the floor and the mattress - Use an air purifier with a HEPA filter - Wash the bedding frequently in hot water - Use protective covers on the pillow and mattress - Replace your pillow and mattress from time to time Supplement: The positive effects of lavender essential oil on sleep have been scientifically demonstrated in most people.
Luminosity	Human beings have an internal clock called the circadian rhythm, which lasts approximately 24 hours. The most powerful synchronizer of this clock is light. Melatonin, also known as the sleep hormone, is a sleep aid. It is strongly associated with lower body temperature, decreased vigilance and performance, and a heightened state of fatigue. It promotes sleep onset. Exposure to typical indoor lighting before bedtime delays the secretion of melatonin by about 90 minutes. Exposure to lighting as weak as 5 lux during the night is sufficient to act on melatonin and modify sleep architecture.	- Dim the light in the evening and avoid all sources of blue light (TVs, computer screens) - Install roller blinds and opaque curtains - Sleep with a blindfold (sleep mask) Supplement: It has been scientifically demonstrated that exposure to a very bright source of light as quickly as possible after waking up in the morning will reduce awakenings and increase the quality of sleep during the next night.
Noises and sounds	Noises and sounds are processed by the brain even during sleep. Among the sources of noise pollution that hinder sleep, urban traffic is the most common. Processing sounds during the night may disrupt sleep cycles by lengthening the amount of time spent in the stages of light sleep (stages 1 and 2) and may consequently reduce time spent in deep sleep (stages 3 and 4). Beyond 10 to 14 awakenings per hour, sleep would be so fragmented that upon waking up in the morning, seniors would be more likely to feel pain.	- Use earplugs - Turn on a machine that emits a constant noise (eg, fan) to mask intermittent noises - Replace the windows - Sleep in a room farthest from sources of noise Supplement: It has been scientifically demonstrated that listening to 20 to 45 minutes of relaxing music before going to bed favors the ability to fall asleep and improves the quality of sleep after about three weeks of daily practice.
Comfort of the mattress	The role of the mattress is to support the spinal column in a similar position to the vertical position, to distribute the weight load equitably and minimize biomechanical stress on some body structures. A comfortable mattress should facilitate necessary changes in posture to avoid overloading the soft tissue and preventing muscle stiffness that can affect the quality of sleep. A moderately firm mattress is recommended. The use of a new, well adapted mattress can alleviate pain significantly and enhance sleep quality. These gains persist six months later, and improvement appears to continue over time.	- Procure a mattress that is well adapted to your preferences and particular needs
Comfort of the pillow	The main role of the pillow is to support the neck bones in an optimal position to reduce biomechanical stress on the spinal column structure. Feather pillows are to be avoided. These pillows were rated lowest in terms of comfort (neck stiffness), quality of sleep and temperature regulation among all types of pillows. When evaluating three thicknesses of latex pillows (5, 10 and 14 cm), the 10 cm version was considered the most comfortable. It also maximally promotes muscle relaxation. Nonetheless, the current state of knowledge does not allow us to precisely affirm which characteristics of a pillow favor sleep in different populations. The choice of a pillow is therefore largely dictated by personal preference.	- Procure a pillow that is well adapted to your preferences and particular needs
Temperature	During both daytime and nighttime, internal temperature and skin temperature interact to attain a balance between heat loss and heat production. Moderate exposure to heat or cold during the night has a negative impact on sleep quality, particularly in older people. During sleep, several factors interact: internal body temperature, skin temperature, ambient temperature, ventilation, humidity rates, night clothes, and bedding. A sleep environment with a temperature between 17°C and 28°C and a humidity rate between 40% and 60% can generally create a microclimate (under the sheets) of 34°C to 36°C, which favors sleep, given the normal body temperature of 36.6°C. Sleep is disturbed more by heat than by cold.	- Choose sleepwear and bedding that is easily adaptable during the night - Use a fan or air conditioner - Install programmable thermostats - Use a humidifier or dehumidifier Supplement: Scientific studies have shown that taking a hot bath 90 to 120 minutes before going to bed benefits sleep. A foot bath before bedtime also has positive effects.

Table 2 Socio-Demographic Characteristics of the Participants

Characteristics	Frequency (n)	Percentage (%)
Gender  Male  Female	19 25	43.2 56.8
Marital status  Married and living as a couple  Living as a couple but not married  Divorced and living alone  Widowed and living alone  Single but previously lived as a couple  Single and never lived as a couple	21 8 7 3 4 1	47.7 18.2 15.9 6.8 9.1 2.3
Education  Primary  Secondary  College  University	1 8 15 20	2.3 18.2 34.1 45.5
Annual income  Less than $20,000  $20,000 to $29,999  $30,000 to $39,999  $40,000 to $49,999  $50,000 and over	5 8 7 11 13	11.4 18.2 15.9 25.0 29.5
Chronic illness  Yes  No	16 28	36.4 63.6
Body mass index (BMI)  Underweight  Normal weight  Overweight  Obese	2 13 21 7	4.7 30.2 48.8 16.3

Table 3 Means and Standard Deviations at T1 (Prior to the Intervention), T2 (One-Month Follow-Up), and T3 (Four-Month Follow-Up)

	T1	T2	T3	F
ISI	11.88 (6.50)^a	10.82 (6.82)^b	8.48 (5.27)^ab	11.500***
Total PSQI score	7.89 (4.23)^a	7.44 (4.40)	6.59 (3.75)^a	5.527**
PSQI components
Subjective sleep quality	1.57 (0.89)^a	1.38 (0.85)	1.13 (0.64)^a	8.186***
Sleep latency	1.29 (1.18)^a	1.37 (1.08)^b	0.97 (0.79)^ab	6.340**
Sleep duration	1.07 (1.00)	0.90 (0.96)	0.83 (0.82)	2.401
Sleep efficiency	1.26 (1.08)^a	1.05 (1.11)	0.89 (1.03)^a	3.506*
Sleep disturbances	1.43 (0.50)	1.43 (0.50)	1.40 (0.54)	0.070
Use of sleeping medication	1.09 (1.34)	1.07 (1.28)	1.07 (1.32)	0.049
Daytime dysfunction	0.93 (0.83)	0.88 (0.82)	0.79 (0.74)	0.732
GAI	5.84 (6.03)^a	5.34 (5.91)^b	3.89 (4.79)^ab	4.978**
GDS	5.15 (4.31)	5.44 (5.14)	5.18 (5.54)	0.217
WHOQOL-BREF domains
Physical health	15.13 (2.61)	15.59 (2.33)	15.81 (2.48)	3.217
Psychological health	15.38 (2.21)	15.60 (2.40)	15.66 (2.26)	1.101
Social relationships	14.98 (3.22)	15.22 (2.78)	15.30 (2.40)	0.433
Environment	16.31 (1.93)	16.42 (1.77)	16.30 (1.85)	0.187
Perception of QOL	4.30 (0.77)	4.40 (0.69)	4.39 (0.69)	0.332
Health satisfaction	3.77 (0.96)	3.91 (0.94)	3.94 (1.00)	1.179
SWLS	28.37 (4.89)	28.23 (5.47)	28.51 (4.67)	0.099
GPM	22.29 (21.86)	23.34 (20.97)	21.62 (19.72)	0.576

Note: *p<0.05; **p<0.01; ***p<0.001; Superscript letters denote significant differences between groups by Bonferroni post hoc analyses.

Abbreviations: ISI, Insomnia Severity Index; PSQI, Pittsburgh Sleep Quality Index; GAI, Geriatric Anxiety Inventory; GDS, Geriatric Depression Scale; WHOQOL-BREF, World Health Organization Quality of Life-BREF; SWLS, Satisfaction with Life Scale; GPM, Geriatric Pain Measure.