This study contributed new insight into changes in the general population’s healthcare seeking for psychological concerns in the early aftermath of large-scale terrorist attacks using pre- and post-attack primary care data from the entire population. It used administrative data on healthcare utilisation in emergency primary care for mental health concerns, both before and after terrorist attacks. The analysis unveiled an overall increase in contacts with emergency primary care for psychological disorders and concerns in the week after the terrorist attacks on 22 July 2011 in Norway. When the population was divided into sub-groups, according to geographical closeness to the attacks, sex and age, the results did not indicate an increase in Oslo, where an attack occurred, but in the rest of the country. Furthermore, a significant increase in the number of contacts were detected for youths, young adults, and middle-aged people, but not for other age groups. Finally, an increase was found for both males and females.
Previous studies that have found reactions among indirectly affected populations when analysing data before and after terrorist attacks have used data from specialised health services and outcomes that are likely to mainly pertain to populations that had either already received mental health treatment [10, 11] or were at elevated risk for conditions of relatively low incidence [9] prior to the attacks. In a gatekeeping system, many of the patients included in studies based on data from psychiatric services will already be in specialised mental healthcare when the attack in question occurs, because healthcare data are studied short-term and referral to these services can take time. Studying data from emergency primary care, on the other hand, will to a larger extent capture contacts that are initiated acutely after the attack in question, because patients generally do not book appointments in advance, but seek help from these services acutely. Moreover, it will cover both contacts that were treated in emergency primary care without further referral as well as those that lead to a referral to specialised mental healthcare.
While this study found an overall increase in contacts for the population as a whole, the results concurrently give reason to stress the importance of distinguishing between different groups of the population, in terms of vulnerability for experiencing reactions. An important task for research is hence to identify these groups. There continues to be uncertainty regarding the mechanism through which the population’s health is affected by the occurrence of terrorist attacks. However, perceptions of proximity, including psychological proximity to the directly affected, or being in geographical proximity to attacks, have been suggested as possible explanations [2, 11, 19]. Contrary to our expectations, the geographical proximity theory could not be confirmed in the current study. Here it is important to note, though, that we examined healthcare contacts due to psychological concerns, and not psychological reactions per se. Psychological reactions do not necessarily lead to healthcare contacts. In the case of Oslo, there is a possibility that the population exerted absenteeism, assuming that the healthcare services would be overwhelmed in the immediate aftermath of the attack. Similar findings were made regarding emergency primary mental healthcare utilization during the initial phase of the Covid-19 pandemic [31]. In addition, the fact that many people across the country knew someone potentially affected by the attacks could be part of the explanation of the increases observed outside Oslo. The attack on Utøya island affected a diverse population in terms of geographical belonging, as camp participants came from all over Norway. Previous research has documented that a relatively high proportion of the population was in psychological proximity to the attacks, e.g., through reporting to have worried about the safety of loved ones, or through knowing someone directly affected by the attacks [2]. Finally, we were only able to evaluate the importance of geographical proximity in the case of Oslo, a large city, but not in the case of Hole municipality, a small community, where the Utøya attack occurred. The importance of geographical proximity might have been more elevated for the population of the smaller municipality than what would be the case in a city, but the design of the current study did not enable us to test this.
At the same time, other studies have observed reactions to terrorism very far away geographically from the attack epicenter, including in other countries [8, 10, 11], suggesting that other factors besides psychological and geographical proximity may be of importance. One such factor could be a perceived social proximity—that is, identifying with direct victims, although not being in any actual psychological or geographical proximity to them. This perceived social proximity could potentially be linked to feeling similar to those directly affected, e.g., in terms of demographic, cultural or socioeconomic characteristics, without actually knowing any victims personally. This could be an additional possible explanation for why an increase in contacts was observed among youths and young adults, as many of those directly affected in the 22 July 2011 terrorist attacks were of that age. Furthermore, it could be a possible explanation for the increase observed among middle aged individuals as these were the same age as many of the parents of the directly affected. This, however, needs to be explored in further studies. Again, there is a possibility that the results in part reflect patterns of healthcare utilisation. The fact that the increase in healthcare contacts due to psychological concerns pertained to certain age groups only does not necessarily mean that the same applied for psychological reactions. Some age groups might indeed have been less likely to access emergency primary care themselves, e.g., children and the elderly.
When separate analyses were conducted for males and females, an increase was found for both groups. Often, the female sex has been reported as a risk factor for developing stress reactions, such as post-traumatic stress disorder [32]. However, not many studies have studied sex differences in health outcomes in the general population after terrorism. Our findings also highlight the importance of not underestimating stress reactions in the male population in the aftermath of terror. Studying contacts with primary emergency care related to mental health could also be particularly relevant when considering the needs of the male population in this regard. In Norway, men are consistently overrepresented in contacting emergency primary care services for psychological disorders or concerns, whereas women are highly overrepresented in seeking help with general practitioners for the same concerns [33]. Studying emergency primary care services specifically could therefore be important in order to capture reactions in both sexes. Nonetheless, given that women to a larger extent tend to seek help with their GP rather than emergency primary care for psychological concerns, our study may have failed to identify potential sex differences in overall healthcare seeking for psychological concerns.
Finally, characteristics of the attacks could also be an explanatory factor for why reactions are observed in certain contexts, but not in others. Byrne et al. [1] discuss whether the lack of mental health reactions observed in the general population in their study could be ascribed to characteristics of the attack studied, which was the March 2019 mosque shootings in Christchurch, New Zealand. More specifically, the attack in their case targeted a minority population in the country. Byrne et al. [1] link this to the extent to which populations empathise or sympathise with the direct victims. An alternative explanation could be linked to perceptions of threat, including whether members of the population perceive that they themselves or someone close to them are unsafe due to the attack [4]. The attacks studied in the current paper targeted members of the majority population, which could imply that larger segments of the population felt threatened.
Strengths and limitations
A major strength of the current study is that it included data on emergency primary care utilisation from the entire population before and after a terrorist attack. This enabled the investigation of potential changes in the wake of the attacks without the selection and recall biases that may hamper survey-based research, or the lack of comparison data that characterises cross-sectional studies. Furthermore, previous studies using registry or administrative data on healthcare utilisation or diagnoses have often only included data from the entire population without information on potential differences according to geographic closeness to the attacks, age and sex. Still, why certain groups appear to be affected more strongly is discussed widely in the literature. The ability to differentiate these groups is a strength of the current study. At the same time, a limitation of this study is that the data utilised were not collected for research purposes. This means that we were not able to isolate factors such as direct exposure to the attacks. Since we used aggregated data, we could also not investigate individual factors such as, e.g., previous history of mental illness. This is a relevant factor given that individuals with previous mental illness at the time of the attack appear to be more vulnerable to experiencing psychological reactions after the event [34]. Furthermore, we could not directly evaluate the importance of psychological proximity, including knowing someone directly affected, which has been found to be associated with increased distress in previous studies [2]. Finally, how contacts are coded by healthcare personnel could potentially lead to error in the data; however, we have no reason to assume that this follows a systematic pattern.
It should also be noted that emergency primary care services will provide consultations for certain psychological or psychiatric disorders more than others. The type of mental health concerns treated at emergency primary care facilities are typically of an acute character, given that these are out-of-hours services that take in patients whose disorder or concern is so serious that treatment cannot wait for them to get in touch with their GP. Strand et al. [9], e.g., found an immediate increase in episodes of schizophrenia/psychosis after the terrorist attacks. These are conditions that will typically require acute treatment, and it could therefore be that our findings in part reflect those of Strand et al. [9]. If this is the case, the current study still provides important information about where in the system health concerns end up needing treatment – in this case, in the primary care services. Furthermore, the current study gives information about reactions in diverse groups of the population, divided according to age, sex and geographical closeness to the attacks. To our knowledge, this has not been assessed earlier.
It should be noted that these data only capture mental health reactions that lead to help-seeking behaviour. There could be reactions in the population that are not captured through this study, because persons did not seek help from the healthcare system, or because the healthcare system does not have sufficient resources to take in everyone. The latter can be particularly relevant in a crisis situation, such as the immediate aftermath of a terrorist attack. Particularly in Oslo, the emergency primary care services had a central role in taking care of individuals affected by the bombing yet with less severe physical injuries or none at all. It is reasonable to assume that this implied a specific strain on the clinics in Oslo, which could lead to a lack of resources to take in other patients. At the same time, the smaller and uncertain estimated change in Oslo could suggest that the observed effects were not due to directly affected individuals only. Furthermore, those directly affected at the government quarters in Oslo received immediate psychosocial assistance through an extraordinary service, organised outside regular services at emergency primary care [35].
An important dimension when considering reactions after terrorist attacks is that of time. Hypothesising a priori what we expect the impact of the intervention to be on the times series is an important, although sometimes overlooked, aspect of ARIMA modelling [28]. Based on findings from previous literature [9], we hypothesised that any change in the number of contacts would be immediate. The study can therefore not say anything about development with more time or any potential long-term effects. However, as time passes, it becomes increasingly difficult to isolate whether the effects measured could be ascribed to the attacks. For this reason, the modelling of effects at longer time spans, with the notable exception of child and maternal health, which can arguably be isolated in a longer time span [6], is challenging.
The study utilised an analytical method that has previously been used in similar studies, and this was done to increase the possibilities for comparison of results, facilitating the isolation of whether any diverging findings are due to different study contexts or different methods utilised. Furthermore, the study utilised aggregated data, so that the method can be replicated in other settings where data availability from registries and administrative databases may be limited to aggregated data only. This is considered an important strength of the current study. A novelty of the approach utilised was to study disaggregated data, according to geographical proximity to the attacks, age, and sex. While this provided valuable information about how the terrorist attacks affected groups of the population differently, this disaggregation came with certain limitations that should be noted. First, the 22 July 2011 terrorist attack occurred in two separate locations: the capital of Oslo and Utøya island in Hole municipality, which both would have been relevant to consider when evaluating the importance of geographical proximity. However, the analysis could only be conducted in the case of Oslo. The utilization of registry data in the current study entailed that the data were anonymous, not only in the presentation of results, but also for the team of researchers conducting the analysis. The population size of Hole municipality was 6,140 in 2011 [36]. This meant that Hole was too small, both in terms of population size and the number of daily or weekly consultations to allow for separate analysis of that municipality. In addition, Hole municipality does not have its own emergency primary care unit but is cooperating with other municipalities in providing this service, which also would have made it challenging to single out consultations from Hole only. For these reasons Hole could not be considered when the importance of geographical proximity was evaluated. Due to the small size of the population, however, any potential increase in the number of consultations in Hole due to geographical proximity to the Utøya attack, would be too small to affect the results covering the entire population, when being compared to Oslo. Second, the disaggregated analysis of different age groups should be interpreted with care, given the disaggregation of the material into a fairly high number of sub-groups and the partly overlapping confidence intervals.
The findings from the current study are not necessarily transferable to all other contexts of terrorism. As warned by Chatignoux et al. [13], for instance, other trajectories may be observed, e.g., in cases of repeated attacks, where stress levels in the population may be elevated over time or develop according to a habituation response [21]. Furthermore, the findings of this study must be understood in the context of primary care in a gatekeeping healthcare system. Still, the findings of this article are important contributions to existing literature in questioning whether pathology should be expected in the population at large after terrorist attacks and establishing the need to differentiate between different subgroups.