Psychological distress refers to non-specific symptoms of stress, anxiety and depression. High levels of psychological distress are indicative of impaired mental health and may reflect common mental disorders, like depressive and anxiety disorders . It is commonly measured with self-report rating scales like the General Health Questionnaire  or MHI-5, derived from the RAND-36 questionnaire . As psychological distress also predicts sickness absences and work disability among the working-age population [4,5], it is important to understand the factors that contribute to psychological distress among those who are working.
According to previous studies, women in the Western world are more prone to psychological distress, depression and anxiety than men [6-9]. Proposed explanations for the gender difference include biological, psychological and social risk factors [10,11]. Social factors involve, e.g. different societal roles and expectations for men and women. The roles at work and in the family as well as the challenges in combining them may be one factor contributing to gender differences [12-14]. However, the combination may also create more content and satisfaction in life, including with respect to possible gender differences .
Work-to-family conflict, family-to-work conflict and work-family enrichment load
Contradictions between work and family, a work-family conflict involves two separate, but related domains. One is work-to-family conflict, also called work-family interference or work interference with family, which occurs when participation in family life is made more difficult by work-related demands . Family-to-work conflict, also called family-work interference or family interference with work, occurs when family life interferes with work . In contrast, work-to-family enrichment means that the experiences at work improve one’s performance and satisfaction within the family [15, 18]. Role accumulation theory claims that multiple roles and meaningful content in life create a positive conception of oneself .
Work-family conflict has been found to be more common in women, although the gender difference in European countries is currently small . Women still perform most of the domestic work in families . Both having children and providing informal care to elderly relatives may increase the experience of work-family conflict . One negative consequence of work-family conflict suggested by previous research is that women may reduce their contribution in work domain and that in turn may hinder career advancement . According to European statistics, when the time spent travelling between home and the workplace and doing unpaid work are taken into account, women work on average 64 hours a week compared to 53 hours for men. Women spend on average 26 hours taking care of children and elderly relatives, whereas men spend only nine hours . It seems that especially during parenting, women have more problems in coordinating work and family life [17, 23, 24].
According to a 2010 European Social Survey, mothers and higher educated employees report the highest rates of work-family conflict . Highly educated parents tend to experience more work-family conflict than less educated parents because of longer working days and greater difficulty in separating work from leisure time. A work position where an individual has much authority and responsibility for making decisions has been found to increase the risk of psychological distress .
Other work-related factors
According to a meta-analysis , a low level of job satisfaction is associated with a higher risk of psychological distress, burnout, anxiety and depression. Significant gender differences in job satisfaction have not been found, although women are less likely to work in managerial jobs and their salary is commonly lower [28, 29, 30].
Mental and physical work strain may affect mental health. Mental strain is common in human service work, but while working in these professions may increase the risk of emotional exhaustion and psychological distress, it may also provide meaning in work . Physical work strain has been found to have a stronger effect on mental health in men than in women .
Social support, loneliness and other social environmental factors
Perceived social support refers to a person’s sense that emotional or practical support is available from others when needed. A lack of social support from one’s partner and close relatives, parents and friends is a risk factor for psychological distress . There are indications that it operates in different ways for men and women , such as the fact that emotional support is more protective against depression for women than for men . Women benefit from support more than men in both work and family contexts  and have more supportive networks than men do . In contrast, women seem to receive less support from their spouses than men do from theirs .
Social support, especially emotional support, is often related to leisure-time activities, such as hobbies or cultural activities, and women tend to gain more benefit from social participation than men [34, 38]. It seems that leisure-time activities are associated with better mental health, especially when they include social contacts, and this is true particularly for men .
Emotional loneliness is the absence of someone to turn to in times of need, while social loneliness is the absence of a social network . Loneliness, which women report experiencing more commonly than men in the general population, co-occurs with mental disorders and psychological distress [41, 42], and its association is partly independent of perceived social support . Accordingly, emotional loneliness is more strongly associated with distress and mental disorders than social loneliness . Among college students, loneliness has a greater impact on women’s mental health than it does on men’s , but differences between genders have not been found among community dwelling adults .
Marital status appears to be a significant feature in loneliness. Marriage, compared to widowhood and divorce, has been found to be associated with better mental well-being in both genders [46, 47], while becoming widowed has more long-term effects among men than among women . Living alone has mostly been associated with a greater risk of experiencing mental health problems , in some studies particularly among men , and men especially experience greater mortality rates from mental disorders than do women . However, findings, especially among elderly people, have also shown that living alone is not associated with reduced emotional well-being  or psychological distress .
Studies on parenting and mental health have mainly focused on how parental stress and depression affects children  and a depressed parent’s behaviour as a parent . Parenthood itself as a risk or protective factor has been studied less often. Some studies have found that parenthood is associated with less mental health problems [56, 57], whereas no association between mental health and parenthood has been found when different types of family statuses, like single parenthood and divorce or living alone, have been taken into account .
Harmful lifestyle factors, like smoking and heavy alcohol intake, have been found to be associated with an increased risk for depressive symptoms [59–62]. Cigarette smoking is more common in lower socioeconomic groups and among people with mental disorders . The comorbidity of substance use disorders with anxiety and depressive disorders is nevertheless common, and it is partly explained by shared genetic liability [64, 65].
Financial difficulties have been found to be a risk factor for reduced mental health [66, 67]. It is not just poverty that causes psychological distress, but also the stigma associated with receiving public assistance . The risk of suffering common mental disorders, e.g. depression and anxiety disorders, among men and women appears different when viewed by income category; women’s risk is greater than men’s risk in all other categories except the lowest one, , whereas financial difficulties in covering household costs seem to have equal negative effects on mental health both in men and women [70, 71].
Informal caregiving, e.g. helping elderly parents, may increase psychological distress, and a recent study has found this to be true for women but not for men . However, other studies have not found an association between informal caregiving and mental health .
Aims of the study
The aim of the current study was to investigate factors contributing to psychological distress among those working full-time, with a special reference to gender differences. A large and representative general population-based survey sample was used, and variables were chosen in the regression models so that they would cover the most important domains that potentially influence psychological distress. Our hypothesis was that factors related to work, family and conflicts in their coordination would be particularly relevant for gender differences associated with psychological distress in the general population.