Loneliness is the subject of many investigations in public health because of its significant prevalence and impacts on health [1]. Loneliness is therefore a public health issue which may affect the entire population [2].
There are several different definitions of loneliness. The most commonly used is that of Perlman and Peplau [3], who describe loneliness as the gap between a person's preferred and actual level of social contact which is a subjective perception.
Researchers have distinguished loneliness from related concepts such as living alone and social isolation [1, 4]. At its most basic level, social isolation has been defined as an objective state of having minimal social contact with other individuals (i.e., emotional loneliness) or to close friends and family (i.e., relational loneliness), which can be self-selected [5].
Perceived loneliness is measured using a variety of more or less standardized tools, leading to confusion about its prevalence in the literature [6].
Then, the prevalence of loneliness among adults varies greatly because of the different tools used, underlying concepts, and populations investigated. In Europe, the average prevalence is 7%, but loneliness is unequally distributed across countries [7]. In France, the prevalence of loneliness is estimated in the general population as being between 10 and 19%, depending on the measurement tools used [8], compared to 27% of people aged 75 and over and 16% for caregivers of older people [9].
Loneliness is an independent risk factor for frailty [10]. Furthermore loneliness is associated with depression, sleep disorders and fatigue [11], with increased risk of obesity [12] and diabetes [13] and adverse outcomes like functional decline and early death [14], emergency visits or early admission in homecare [15]. Risk factors for loneliness include living alone [16], loss of a partner, poor social networks and resources, low socioeconomic status [17], and poor physical and mental health [18].
The factors associated with loneliness vary according to age and life stages [19]. Indeed, loneliness has a non-linear trajectory according to age and affects specific age groups, such as young adults or the oldest old persons, especially in relation to low income levels, greater functional limitations or relational status.
Family caregivers (FCGs), especially those of older people, are particularly affected by loneliness [20]. FCGs are defined as people who provide unpaid, ongoing assistance to people with long-term conditions or limitation in activities of daily living (ADLs), such as grooming, feeding, bathing, walking, dressing, or instrumental activities of daily living (IADLs), such as shopping, meal preparation, housekeeping, and managing finances [14].
In France, there are 15 million FCGs [21], corresponding to 1 in 6 inhabitant.
Informal caregiving by FCGs is important to the health and social care systems because it supports those with disability in their own homes for longer [22]. The reliance on such informal care will increase in the coming decades given the demographic projections of an aging world population [23].
Providing health and/or social care is not without consequences for FCGs who can experience adverse impacts on their physical and mental health [24] and even decreased life expectancy [25], as a consequence. Factors associated with higher burden on FCGs, include the high number of hours spent caring, a poor relationship with the care recipient [26] or poor social networks [27].
Most studies on loneliness target specific populations such as older people or the vulnerable, e.g. with a financial and social vulnerability [28]. Few studies have focused on FCGs who have their personal and social environment reduced due to the lack of time left after their professional life and their caregiving relationship [29]. It is therefore important to explore the loneliness of FCGs.
Thus, we hypothesized that the loneliness of FCGs is a factor related with their burden, health, and frailty. The main objective was to study factors related to loneliness of family caregivers caring for independent older people.