Utilization of somatic specialist services among psychiatric immigrant patients: the Norwegian patient registry study

An alarmingly high proportion of mental disorder patients have a higher risk of morbidity and mortality, particularly patients with severe mental disorders such as schizophrenia, bipolar disorder, or depression [1‐6]. The high burden of somatic diseases is the main contributor for excess morbidity and mortality, i.e., about 60% of excess mortality is due to somatic problems [7, 8]. In particular, cardiovascular diseases (CVD) and infectious diseases (e.g., pneumonia, tuberculosis and chronic viral infections) are identified as major comorbid somatic diseases in patients with mental disorders [9‐11]. For example, a review of studies reported that people with depression have a 50% greater risk of CVD [12]. The prevalence of hepatitis among people with severe mental illness is approximately 5 to 11 times higher than the estimated population rates of this infection [12, 13]. Studies have suggested that such somatic comorbidities may even be greater among immigrant psychiatric patients, particularly among refugees with post-traumatic stress syndrome and depression [14, 15].

Despite such a high burden of somatic comorbidities, rates of undiagnosed and untreated somatic illness are greater in mental disorder patients than in the general population [16]. Mental disorder patients are also subject to unacceptably high levels of disparity in healthcare access and utilization, which contribute to poor somatic health outcomes [16]. In particular, such disparities could be much worse among immigrant patients where underutilization of healthcare services is highly prevalent compared with non-immigrant patients [17, 18]. For instance, our recent research work found that the majority of immigrant groups in Norway have generally lower utilization rates of specialist mental healthcare compared to ethnic Norwegians [19]. However, there is little research investigating utilization of somatic medical services among psychiatric immigrant patients. This study therefore aims to examine the use of specialist somatic healthcare services among psychiatric patients with and without immigrant backgrounds.

Mental ill individuals in general may face a number of barriers to use and access to healthcare services, which are associated with patient- and illness-related factors as well as factors related to healthcare providers and the healthcare system. Such factors may influence the recognition and management of somatic illness. Particularly, patients with immigrant backgrounds may experience a number of such barriers. For instance, they might lack information regarding the healthcare system, little knowledge about health behaviours, or inconsistencies between their expectations and what healthcare providers are able to offer [20]. Moreover, access to care might not be straightforward, as a result of waiting lists or a tendency for lower medical referral rates amongst immigrants. Such factors can impact upon an already under-utilised system leading to significant unmet needs amongst psychiatric immigrant patients.

In this study, we therefore aimed to examine differences in the utilization of specialist somatic healthcare between immigrant and ethnic Norwegian psychiatric patients. Specifically, the study describes differences in rates of outpatient visits and hospital admission for circulatory system diseases and infectious diseases since psychiatric patients seem to be particularly affected by these disease categories. The rationale of the study is to identify utilization patterns of somatic healthcare which could suggest specific needs among immigrant psychiatric patients compared to ethnic Norwegian psychiatric patients. The empirical knowledge provided by this study will ultimately inform about inequalities in use and access to somatic healthcare, which will be vital in efforts to improve the coordination of care across the somatic and mental healthcare delivery system for vulnerable groups.

Our study found that the majority of non-Western immigrant patients have lower rates of utilization of somatic healthcare services for diseases of the circulatory system. In particular, the rate of hospitalization was significantly lower in most immigrant groups, except for psychiatric patients with African backgrounds. Prior research findings have revealed that immigrant psychiatric patients, particularly refuges and asylum seekers, have a higher burden of somatic comorbidities, e.g., hypertension, diabetes and cardiovascular diseases [14, 15, 22, 23]. Based on this evidence, we suggest that underutilization is likely among non-Western immigrants, in the sense that comorbidities between mental disorders and circulatory system diseases that would normally trigger specialist healthcare for Norwegians, do not lead to specialist healthcare for many non-Western immigrants. Specifically, it seems that under-utilisation of somatic healthcare services is unlikely to be due to lack of availability or need. This may lead to lack of detection or treatment of circulatory system diseases in immigrant psychiatric patients, or late diagnosis resulting in poor prognosis, treatment responses and outcomes [9, 24, 25].

In contrast, we found less disparities in the utilization rates of somatic specialist healthcare for infectious diseases, especially for the outpatient services. The findings rather reveal that African psychiatric patients had higher outpatient and hospital admission rates for infectious diseases. This could be due to the heightened attention given to screening on arrival and management of infectious diseases among immigrants, especially for those from high burden countries, e.g., African immigrants. Such increased attention from both health personnel and policy makers towards prevention and management of infectious diseases could contribute in reducing inequalities in access and utilization of somatic care for infectious diseases as well as improve coordination of care across the somatic and mental healthcare delivery system.

This study indicates that immigrants from non-Western countries are especially faced with a double barrier to health care. As shown in an earlier paper, immigrants have less utilization of mental health services in general [19], and those who access mental health services have a higher barrier to get somatic services. There is an urgent need to inform policy makers and health care workers about these disparities and address them accordingly.

One strength of the present study is that it has investigated use of specialist somatic healthcare among immigrants with high-quality register data which cover the entire population, implying that selection bias is practically absent. Only a very small number of private-practising physicians, psychologists, psychiatrists and hospitals are not obliged to report on their activities to the Norwegian Patient Registry. Thus, the patients analysed here will cover practically all patients in specialist psychiatric care during the study years, and the estimated utilization rates in specialist somatic healthcare are likely to be quite precise. Another strength is that the data provided by Statistics Norway include all registered immigrants in Norway, meaning that each immigrant world origin was represented by a sample of usable size. Further, the registry offers data concerning the origin of patients making it possible to explore based on world regions of origin rather than heterogeneous groups, i.e., western vs. non-western immigrants or immigrants from high vs. low income countries. The study period 2008–2011 coincides with the ‘Great Recession’ in Europe which was followed by austerity measures in the health care of many countries. However, since the international financial crisis had few effects in Norway, the time period analysed here did hardly differ from previous or later years.

Various limitations may nevertheless have affected the reported results of this study. The outcome variables indicate whether the psychiatric patients had at least one outpatient visit or at least one hospital admission for circulatory conditions or infectious diseases during the observation period, but they do not distinguish between few and many visits and hospital stays. Only registered inhabitants are included on the register, thereby, migrants staying in Norway without being registered, and asylum seekers whose applications have not been decided on, are not part of the analyzed samples, implying that particularly vulnerable migrants are not analysed here. A weakness which affects the present study as well as most other investigations based on administrative registers, is that the information available is often very limited and possibilities for testing hypotheses and detailed explanations will be restricted. Research of the themes addressed in this study will benefit from data more suitable for exploring explanatory mechanisms.

This study has served to highlight significant differences in the uptake of somatic healthcare services for circulatory diseases between psychiatric patients based upon their world regions, though there are less variations for infectious diseases. Underutilisation of hospitalisation is most likely amongst patients from Asia and Latin America. The findings suggest that interventions addressing inequalities in access to and utilization of somatic healthcare should primarily target non-Western psychiatric immigrant patients with diseases of the circulatory system. Policy-makers and service providers should try to implement measures which improve the responsiveness of somatic healthcare services to the needs of psychiatric immigrant patients. Such measures should emphasize a much stronger follow up of somatic disorders in mental health care and an improved cooperation between mental and somatic health care.