This study is part of a recent Administrative Data Research initiative, funded by the United Kingdom (UK) Economic and Social Research Council (ESRC), to develop the use of routinely collected administrative data for research purposes. In this instance the population of interest is drawn from the Northern Ireland (NI) 2011 Census enumerated population. While the general mechanisms involved in evolving and building the database spine (in this case the whole enumerated 2011 Census population) are detailed elsewhere [22, 23], the data linkages for this study include both this and electronically captured data on medications prescribed through Primary Care and dispensed by pharmacists, data gathered initially for pharmaceutical audit [22] and held on the Business Services Organisation (BSO) Enhanced Prescribing Database (EPD). The databases are managed and maintained by the Northern Ireland Statistics and Research Agency (NISRA): all data is classed as confidential; is held in, and accessed from, a secure setting; by accredited researchers, each of whom must adhere to stringent protocols obviating disclosure issues; and using data de-identified prior to researcher access.

The study population included 109,627 persons aged between twenty and fifty-nine (women), and twenty and sixty-four (men) in the 2011 Census: 61,639 females and 47,988 males, of whom 33,338 (54.1%) and 9,702 (20.2%) respectively were employed in the Health and Care (HSC) Sector. For both groups the residual populations comprised a reference group of professionals not involved in health and care (Table 2). Overall, 1.93% (n = 2,116) of people working in the HSC sector self-reported chronic mental health problems at census, and 15.18% (n = 16,639) psychotropic drug use for a common mental disorder (Table 1). In most cases, relative to the reference population, those in the HSCare sector were more likely to obtain psychotropic medication.The frequency of psychotropic drug use is higher among those in nursing (19.47%: n = 2,459), welfare (20.22%: n = 775), formal caring (26.49%: n = 3,933) and management (21.83%: n=222) roles than the other occupation groups. These groups also record higher levels at ten or more prescriptions: 4.71%, 5.14%, 7.25% and 4.92% respectively for each. However, HSC managers are, in absolute terms, a very small group within this sector.

Table 2 reports both the numbers (and proportions) of the various sub-populations of interest in the study, and the Odds Ratios (ORs) associated with self-reported mental health problems and psychotropic prescription receipt. Models are stratified by gender and fully adjusted for socio-demographic and socio-economic associations and HSC occupation type (with this indicator the reference group comprises all those in full-time employment in professional occupations other than in HSC occupations). A number of the cells in the frequency columns were classed by the data custodians as disclosive. To obviate this problem we had to remove the equivalent cells from male/female frequencies.

Self-reported mental health problems were higher in females working in a formal welfare role (OR = 1.35: 95%CI = 1.04–1.74). As expected, excess likelihood for receipt of psychotropic medication were recorded for both males and females employed in nursing, welfare and formal caregiving roles. Males in managerial roles and those working as therapy professionals also recorded higher likelihoods of CMD, with psychotropic prescription use (OR = 1.55: 1.07–2.25 and OR = 1.48: 1.01–2.15 respectively).

More generally, while self-reported mental health problems increased with age, minority ethnic status appears protective (OR = 0.41: 0.26–0.65 and OR = 0.56: 0.32–0.97 for females and males respectively when compared with their white peers), as does marriage and higher educational qualifications. Excess likelihoods were noted for those in rented housing (when compared against those in owner-occupation). Excess likelihoods were recorded for men in a lone parenting role and for women in an informal caring role (OR = 1.65: 1.12–2.42 and OR = 1.16: 1.02–1.33 respectively).

Factors associated with psychotropic medication for both men and women mostly follow the patterns described above: for example, marital status, household car access, and locale of residence; age and ethnicity. Excess likelihoods were recorded for women in a lone-parenting role (OR = 1.27: 1.17–1.37) and for both women and men in an informal caring role (OR = 1.15: 1.09–1.21 and OR = 1.18: 1.09–1.28 respectively). Finally, excess likelihoods were recorded for those in rented housing when compared with the most affluent owner-occupation (OR = 1.56: 1.35–1.79 and 1.51: 1.29–1.77 for women and men respectively).

Table 3 shows the sex-specific relationships between HSC occupation role and number of prescribed medications, firstly age-adjusted and then fully adjusted (with those receiving no medication as the reference category). For brevity and to allow focus, only the findings for HSC occupations are presented. The extended findings are available on request. For women, both the age-adjusted and fully adjusted models are consistent: nurses, welfare professionals and care workers show excess likelihoods across all prescription groups (with the exception of care workers receiving twenty or more). However, while women in HSC management roles show higher (age-adjusted) ORs this excess disappears on full adjustment. For men similar patterns were recorded: higher levels in nursing, welfare and caring occupations.

This study confirms evidence that people working in the caring sector are at higher risk of poor mental health outcomes when compared to other occupations. This is all the more compelling because we have obtained not only data on self-reported mental health problems but separately obtained administrative data on receipt of psychiatric medication. Investigations of the use of psychotropic drugs employing data from population-based studies are justified by the high and increasing prevalence of the consumption of these drugs in particular segments of society, especially anxiolytics and antidepressants [25]. However, we only note dispensed prescriptions and cannot identify usage or therapeutic drugs prescribed in the absence of mental illness. Importantly too, our findings show that even within health and social care, some jobs carry more risk of mental illness than others, with social care workers having exceptionally high levels of psychiatric medication compared to other health professions and the general population. Socioeconomic circumstances, unsurprisingly, were also associated with higher risk of mental health problems, as was lone-parent status and low educational attainment.

However, we additionally show that informal caregiving greatly increases the risk of mental health problems among men and women, supporting earlier evidence on the challenges of caring [18]. There is a considerable body of evidence that family or informal caregivers are at high risk of stress and common mental disorders [26, 27]. However, variation in caregiving risk is often mediated by age, gender, relationship, condition and symptoms [28]. While we were unable to show which caregiver or care-receiver factors influence these outcomes, we could show that caregiving, independent of other major socioeconomic factors, contributes to poor mental health. We noted that minority ethnic status appears to be protective against mental health problems, with this finding on self-reported ill-health replicated in other studies [18]. This may reflect an emergent healthy migrant effect, that immigrants self-report a better health status than natives [29], or cultural differences related to stigma, explanatory models of mental illness or lower access to primary care [30].

Previous studies have shown that, regardless of age, those self-reporting poor mental health were more likely to redeem antidepressant prescriptions [31]. This contrasts with our study, where self-reported mental health status is derived from the census. Again, this may be the stigma of mental illness, deterring people from seeking medical help or access to non-medical treatment [31].

Work and personal relationships are central to daily life and powerfully influence well-being. It may be the case that health professionals because of their knowledge and expertise feel less stigmatised by mental illness and are therefore less inhibited to seek help and medication, compared to non-health sector. However, in the UK over the past decade the HSC workforce, their organisational setting and mental health outcomes, have received growing attention [5].

National Health Service (NHS) staff work under the impact of fiscal austerity and funding cuts, in services under intense pressure, with professional apprehensions about quality of care, patient safety and staff retention [32]. The NHS is the world’s fifth largest employer with a workforce of 1.7 million, with reported sickness absence at 3–4% and over a quarter of staff illness attributable to mental ill-health [33]. An earlier UK based study reported that the prevalence of psychiatric disorder amongst health associated professionals was slightly lower than the average amongst all workers (11% compared to an overall prevalence of 13%). However, certain occupations within the healthcare sector had a higher prevalence of psychiatric disorder than expected, for example, nurse auxiliaries and care assistants [34].

More recently, data from the Second UK Survey of Psychiatric Morbidity amongst adults living in private households in Britain reported higher prevalence of CMD in occupations including primary and secondary teachers, welfare community, youth workers, security staff, waiters, bar staff, nurse auxiliaries and care assistants [3]. These occupations involve an emotional labour in working closely with the general public, including a degree of responsibility and unpredictability in personal interactions. High expectations from the public, risk of violence and verbal aggression can result in the professional masking their personal emotional needs to their detriment in terms of mental health [3]. Other studies have found that those working in minority, typically female dominated occupations such as teaching, healthcare and social work, are at increased risk of CMD. However, selection may account for this too [35]. Nevertheless, high levels of staff absence have important economic consequences and are negatively associated with healthcare service quality, including patient safety and effective patient care [33]. Dealing with this challenge across the NHS is parallel to analogous challenges existing around funding of HSC services [5, 6].

A possible explanation for higher CMD among those working in the HSC sector might relate to increased exposure to psychological distress, including role conflict, emotional labour, risk of medical error/litigation and strained relationships with patients/caregivers [36]. High job stress, low reward and moral injury have led to staffing shortages which contribute to increased stress across HSC professions due to fragmentation of responsibility for workforce issues at a national level; poor workforce planning; cuts in training place funding; insecurities surrounding potentially restrictive immigration policies exacerbated by Brexit rhetoric; and high levels of healthcare providers leaving their jobs prematurely. Staff shortages increase workload for those remaining and, with on-going staffing deficiencies, patient waiting lists will increase and quality of care diminish.

Protecting the mental health of those working in HSC is imperative, and career appropriate support should be available [37] to improve job-related difficulties [38]. High staff turnover is associated with mental ill-health [39] and is detrimental to budget maintenance in medical institutions [40]. The trends in psychotropic treatment might represent over-prescribing and lack of access to psychological therapies. Psychotropic medication uptake within the workplace in the absence of self-report might be stigma-related. Furthermore, self-reported mental illness and lack of psychotropic treatment appears to be associated with socioeconomic inequity. It might be argued that these are contextual issues. First, different from other UK jurisdictions, HSC is integrated in NI. However, while integrated care should be beneficial to staff, evidence of high levels of CMD presented here suggests otherwise. According to the recent Bengoa Report [41] recommendations to improve workforce strategy have not yet been adequately implemented. Cutbacks in funding are also blamed for a lack of progress on full implementation of earlier Bamford recommendations and roll-out of good practice initiatives across NI. Organisational context is an important contributor to the uptake of psychotropic medication among employees. Policy-makers should consider how to implement organisational change in the workplace, providing appropriate interventions and improving conditions that currently may pose risks for employee mental health.