Social determinants of sleep quality: association between sleep quality and living environment among older individuals

Healthy sleep contributes to the prevention of various chronic diseases and improves health outcomes [1]. Many epidemiological studies have shown that ensuring sufficient sleep is beneficial for maintaining good health [2, 3]. Although sufficient sleep is important for all age groups [3], insufficient or excessive sleep has been shown to have an alarming impact on health and mortality outcomes, especially in the elderly [4]. Recently, it has become clear that ensuring sleep quality is also important for maintaining good health [5–7]. Individual measures have been focused to address poor sleep quality, which can be caused by chronic diseases, including sleep disorders and chronic medical conditions, medications prescribed for them [8], and poor sleep hygiene, including sleep environment, lifestyle, and personal preferences for alcohol, caffeine, and nicotine [9].

Recently, social determinants of health based on social disparities and other factors have gained attention [10]. Generally, this is a concept for environmental and attributional factors that are difficult to address adequately through individual efforts, including economic status, living environment, educational opportunities, employment, access to medical care, and so on [11]. This is a notable topic because it is likely to affect sleep health as well.

In the issue of Sleep and Biological Rhythms, Wang and the coauthors examined the relationship between sleep quality and living environments in older individuals residing in urban and rural areas of Anhui Province, China [12]. Sleep quality was measured using the Pittsburgh Sleep Quality Index (PSQI), and sleep dysfunction was recognized as the cutoff point (10 <) of the PSQI total score. Multivariate logistic regression analysis indicated that living alone and in rural areas were significantly associated with a high incidence of sleep dysfunction. Living near a park and footpaths suitable for exercise or walking were significantly associated with a low incidence of sleep dysfunction. Additionally, individual factors, such as women and depression, have been associated with a high incidence of sleep dysfunction [12].

Various studies have reported these factors as those that can worsen health [13], and worsening sleep quality may be an intervening factor. Physiological interventional studies have demonstrated that increased physical activity improves sleep quality [14], and living in an environment conducive for physical activity can contribute to improved sleep quality.

As the authors discussed sleep quality is determined by combined factors [15], improving these social determinants of sleep health should be considered, regardless of the importance of the causal relationship. The current study may motivate further work on obtaining all the facts about the social determinants of sleep health, as no one will be left behind in the wave of social sleep health promotion.

Declarations

Conflict of interest

KK has received grant support from Otsuka Pharmaceutical Co., Ltd, and Shionogi Pharma, Eisai, MSD, and Takeda Pharmaceutical Co., Ltd; personal fees from Meiji Seika Pharma, Eisai, MSD, Takeda Pharmaceutical Co., Ltd, Mitsubishi Tanabe Pharma and Sumitomo Pharma; advisary fees from Eisai, Shionogi Pharma, and Nxera Pharma outside the submitted work.