Introduction
Schizophrenia is considered one of the most disabling psychiatric illnesses in the world.Reference Harvey and Strassnig 1 , Reference Murray and Lopez 2 Schizophrenia is incredibly complex and impacts not only the individual suffering from this illness, but also the families and communities who often struggle with finding ways to support and care for them.Reference Ayano, Tesfaw and Shumet 3 Schizophrenia is most often associated with the presentation of its positive symptoms (eg, hallucinations, delusions, thought disorganization, and paranoia) and negative symptoms (eg, alogia, blunted and flat affect, stereotyped behaviors and thinking, and social withdrawal) that are used to diagnose the psychiatric illness. Thus, many outcome studies focus on the reduction of these symptoms as measured by such instruments as the Positive and Negative Syndrome ScaleReference Kay, Fiszbein and Opler 4 (PANSS) or the Brief Psychiatric Rating ScaleReference Overall and Gorham 5 (BPRS) for measuring the presence and severity of symptoms associated with psychiatric disorders such as schizophrenia. While these instruments have strong psychometric properties and measure an important aspect of the illness, the impact of schizophrenia on functional outcomes goes beyond just the symptomatology of the illness. For instance, individuals with schizophrenia have higher mortality rates and experience more health issues, cognitive deficits, and functional capacity limitations. These individuals have greater involvement in the criminal justice system, increased risk of being both the victims and perpetrators of violence, increased rates of homelessness, and often struggle with everyday functioning. Moreover, they report lower levels of QoL.
While these topics have been researched by others, to this author’s awareness, there has not been a paper that synthesizes the mortality, cognitive, criminal justice, violence, and QoL-related functional outcomes of schizophrenia. Moreover, this paper will discuss the impact that pharmacology and outpatient services can have on improving these broader functional outcomes. The author posits that to promote a more holistic, integrated, and meaningful life, clinicians, researchers, and policymakers need to have a broader conceptualization of “real-world” functional outcomes in individuals diagnosed with schizophrenia that extend beyond just management of psychosis symptomatology.
Mortality rates and health status
The diagnosis of schizophrenia is associated with one of the highest mortality risks of all psychiatric disorders.Reference Vermeulen, van Rooijen, Doedens, Numminen, van Tricht and de Haan 6 Studies have suggested that individuals diagnosed with severe mental illness (including schizophrenia) die 15–20 y prematurely compared to the general population.Reference Vancampfort, Rosenbaum and Schuch 7 While the reduced lifespan with individuals diagnosed with schizophrenia is well documented, the underlying causes are less understood. In a systematic review and meta-analysis of 135 cohort studies comparing 4.5 million individuals with schizophrenia to 1.11 billion individuals in the general population, Correll and colleagues examined the risk and attenuating factors associated with mortality in people with schizophrenia.Reference Correll, Solmi and Croatto 8 Their findings revealed that the all-cause mortality rates in individuals diagnosed with schizophrenia was 2.9 times higher when compared with the general population.Reference Correll, Solmi and Croatto 8 A lower but still statistically significant 1.6-fold increase in all-cause mortality was observed when compared with diseased-matched general population controls.Reference Correll, Solmi and Croatto 8
Suicide was identified as the highest relative risk factor for individuals diagnosed with schizophrenia. Specifically, Correll and colleagues identified a 9.7-fold increase in relative risk in mortality by suicide, as well as a 7.4-fold increase in relative risk for all-cause mortality for first episode schizophrenia when compared with the general population.Reference Correll, Solmi and Croatto 8 The suicide-related mortality risks were higher for those individuals who were under the age of 40 y.Reference Correll, Solmi and Croatto 8 While not examined specifically in this study, others have highlighted that suicide attempts increase with severity of psychotic and depressive symptoms at first psychotic episode.Reference Díaz-Caneja, Pina-Camacho, Rodríguez-Quiroga, Fraguas, Parellada and Arango 9
Non-natural causes of mortality, including poisoning (8- to 9-fold increase) and pneumonia (7-fold increase), were also higher when compared to the general population.Reference Correll, Solmi and Croatto 8 The mortality risk remained higher in individuals diagnosed with schizophrenia for infectious, respiratory, and endocrine diseases (3.7- to 3.8-fold increase), as well as injury or accidents (3.3-fold increase) when compared to the general population.Reference Correll, Solmi and Croatto 8 Unlike suicide-related mortality, natural cause mortality was not observed as being higher in those under the age of 40 y. Comorbid substance use disorder (SUD) increased all-cause mortality as well, which is most likely related to the adverse physical impact of substances, as well as the adverse impact related to injury and suicide-related behaviors.Reference Correll, Solmi and Croatto 8 Substance use in general, but particularly cannabis use, was associated with poorer antipsychotic medication adherence.Reference Correll, Solmi and Croatto 8
Overall, these findings support the significant impact that schizophrenia has on outcomes related to all-cause mortality compared to the general population. The importance of early and accurate diagnosis, suicide and SUD screening, and treatment in individuals with schizophrenia is critical to reducing these relative risks.Reference Correll, Solmi and Croatto 8 Moreover, these findings highlight that earlier detection and treatment are critical for better health and mortality outcomes for individuals diagnosed with schizophrenia.
Functional capacity in everyday functioning
Aside from mortality rates and lifespan, arguably one of the most disabling impacts of schizophrenia is on an individual’s ability to manage everyday life. While seemingly straightforward, operationalizing everyday functioning can be quite challenging as there are many abilities and factors that go into these daily activities, including stable employment, social connections, and independent living. To navigate the demands of daily living, a person must have the ability to perform the necessary life skills, the motivation to perform these skills, and the situational recognition to know when these skills are likely to be successful.Reference Harvey and Strassnig 1 Undergirding the ability, motivation, and situational recognition of everyday functioning is a complex interconnection of cognitive performance, functional capacity, social cognition, clinical symptoms, fitness and health status, and environmental factors.Reference Harvey and Strassnig 1 While all of these are important, this section will focus on the impact of schizophrenia on cognitive performance and functional capacity in daily life tasks.
Cognitive functioning, as measured by neuropsychological assessment, is comprised of specific domains including attention, language, memory and learning, processing speed, and executive functioning. Deficits in these areas can impact a person’s ability to efficiently and effectively perform the daily tasks of life. As summarized in Harvey and Strassnig, several studies have shown small-to-moderate correlations between individual cognitive domains (eg, attention) and global indices of everyday functioning.Reference McClure, Bowie and Patterson 10 Composite scores (ie, multiple cognitive domains), on the other hand, show moderate-to-large correlations with everyday functioning.Reference McClure, Bowie and Patterson 10 , Reference Green, Kern, Braff and Mintz 11 Cognitive function is strongly associated with independent residential living,Reference Bowie, Leung and Reichenberg 12 which is a critical aspect of everyday functioning. While cognitive performance is clearly associated with everyday outcomes (eg, independent living), there is a growing body of literature on the concept of functional capacity as a more direct correlate of day-to-day functioning.
Functional capacity is defined as “an individual’s capability, under controlled conditions, to perform tasks and activities that are necessary or desirable in their lives.”Reference Patterson and Mausbach 13 (p.13) Given these elements, assessing functional capacity must take into consideration the specific task or ability, the context this is being performed in, and the nature of the disorder or disability that is impacting an individual’s functioning.Reference Patterson and Mausbach 13 Studies have found that measures of functional capacity are similarly correlated with performance-based neuropsychological measures on real-world functional outcomes.Reference Harvey and Strassnig 1 , Reference Bowie, Leung and Reichenberg 12 While it is still unclear as to how exactly cognitive performance and functional capacity interact to impact everyday function, there is growing evidence that functional capacity has a more direct role.Reference Harvey and Strassnig 1 Understanding the impact of cognitive and functional capacity deficits is critical, as there are specific cognitive rehabilitation interventions that can target these areas of challenge. Clinicians, researchers, and policymakers would be remiss if they did not consider cognitive and functional capacity dimensions when conceptualizing real-world functioning.
Criminalization, violence, and homelessness
It is well documented that individuals with serious mental illness (SMI; eg, schizophrenia, bipolar disorder, schizoaffective disorder) are at increased risk of arrest and incarceration.Reference Van Dorn, Desmarais, Petrila, Haynes and Singh 14 , Reference Munetz, Grande and Chambers 15 Reports have indicated that approximately 14% of state prisoners, 8% of federal prisoners, and 26% of jail inmates have reported symptoms that are commensurate with “serious psychological distress.”Reference Maruschak, Statistician and Bronson 16 , Reference Bronson 17 Moreover, about 43% of state and 23% of federal prisoners had a history of mental health problems.Reference Maruschak, Statistician and Bronson 16 Individuals with schizophrenia who are incarcerated often experience disruptions in their treatment and can experience significant increases in symptomatology while languishing in jails and prisons. Much has been written on the topic of the criminalization of the mentally ill, and readers are encouraged to review those resources.Reference Warburton and Stahl 18
While most individuals with schizophrenia are not violent, the presence of psychosis is a well-established risk factor associated with violence.Reference Douglas, Guy and Hart 19 Specifically, individuals with schizophrenia had a 6-mo prevalence of 19%, with approximately 3.6% of those constituting “serious violent behavior.”Reference Swanson, Van Dorn, Monahan and Swartz 20 Serious violent behavior was associated with positive psychotic symptoms (eg, persecutory ideation), depressive symptoms, childhood conduct problems, and victimization.Reference Swanson, Van Dorn, Monahan and Swartz 20 A similar prevalence of violence in 2–13% of outpatient individuals within a 6-mo to 3-y time frame has been observed by others.Reference Choe, Teplin and Abram 21 While the public tends to be more concerned that individuals with schizophrenia are highly likely to commit acts of violence, the research indicates that individuals with SMI are more likely to be the victims of violence. Compared with 2–13% of individuals with SMI perpetrating violence, 20–34% had been violently victimized within the same time frame.Reference Choe, Teplin and Abram 21 Studies that combined both inpatient and outpatient samples reported that 12–22% had perpetrated violence in the past 6 to 18 mo as compared to 35% who were the victims of violence during that same period.Reference Choe, Teplin and Abram 21
Many factors contribute to homelessness, including victimization of violence (such as domestic violence), poverty, disability, unemployment, adverse childhood experiences, substance abuse, and the presence of SMI.Reference Ayano, Tesfaw and Shumet 3 Individuals who are homeless have a higher prevalence of psychiatric disorders, including schizophrenia.Reference Ayano, Tesfaw and Shumet 3 A meta-analysis of 31 studies involving 51,925 individuals worldwide showed a higher prevalence of psychosis (21.2%) and schizophrenia (10.3%) among homeless people.Reference Ayano, Tesfaw and Shumet 3 Homelessness among those with schizophrenia was higher in developing (22.2%) as compared to developed countries (8.9%).Reference Ayano, Tesfaw and Shumet 3 Overall, this meta-analysis highlights that schizophrenia has a significant impact on incarceration rates, being both the perpetrator and victim of violence, as well as homelessness.
Quality of life
Most of the research reviewed for this paper examined “objective” functional measures associated with a diagnosis of schizophrenia. However, an important overlooked perspective associated with schizophrenia is the subjective experience of the one diagnosed with this disabling psychiatric condition. The literature on QoL for those diagnosed with schizophrenia is complex and often contradictory due to a host of factors, including differing operational definitions, measurement methodology (eg, subjective QoL vs. “objective” measures of QoL), domains measured (eg, physical, psychological, social, and health-related), and the impact of symptom severity and the level of insight.Reference Eack and Newhill 22 , Reference Bobes, Garcia-Portilla, Bascaran, Saiz and Bouzoño 23 Early research raised doubt as to the “accuracy” of subjective QoL judgments due to the cognitive impairments and lack of insight related to schizophreniaReference Bobes, García-Portilla, Sáiz, Bascarán and Bousoño 24 and findings of poor agreement in self-ratings as compared to the clinician and family members.Reference Sainfort, Becker and Diamond 25 However, studies have shown that individuals with schizophrenia are able to accurately report on their social deficits and living situations,Reference Skantze, Malm, Dencker, May and Corrigan 26 and comparable convergent validity in perceptions of QoL between individuals and clinicians has been observed.Reference Lehman, Postrado and Rachuba 27 While there are many ways to define the concept, arguably the most recognized definition of QoL is “an individual’s perception of their position in life in the context of the culture and value systems in which they live and in relation to their goals, expectations, standards, and concerns.” 28 Relevant to the current paper, recent meta-analyses elucidate the relevance of QoL in the conceptualization of functional outcomes associated with schizophrenia.
There is considerable variability in the findings of published studies regarding QoL among individuals diagnosed with schizophrenia. Several recent studies, including two meta-analyses, examining individuals diagnosed with schizophrenia consistently report lower levels of QoL in domains of physical and psychological health, environmental domains (eg, accessing resources), and in social relationships when compared to the general population and healthy controls.Reference Bobes, Garcia-Portilla, Bascaran, Saiz and Bouzoño 23 , Reference Dong, Lu and Zhang 29 , Reference Attepe Özden, Tekindal and Tekindal 30 Longer durations of illness, symptom severity, poverty, and earlier onset of illness were associated with lower subjective reports of QoL.Reference Bobes, Garcia-Portilla, Bascaran, Saiz and Bouzoño 23 , Reference Migliorini, Harvey, Hou, Wang, Wang and Huang 31 While subjective ratings of QoL can vary significantly over a person’s lifetime, one study found the most significant predictor of subjective QoL was age at time of illness onset, with later onset being associated with higher levels of QoL.Reference Migliorini, Harvey, Hou, Wang, Wang and Huang 31 In this study, earlier age at onset of illness was associated with more relapses, hospitalizations, and poorer outcomes associated with social, occupational, and general functioning.Reference Migliorini, Harvey, Hou, Wang, Wang and Huang 31
Overall, these studies underscore the value of considering QoL when conceptualizing overall functional outcomes. As several studies observed, QoL ratings can fluctuate over the course of one’s life and that despite all of the challenges associated with schizophrenia, some groups reported their subjective QoL to be good.Reference Migliorini, Harvey, Hou, Wang, Wang and Huang 31 In the next section, we will examine the impact of pharmacological treatment and outpatient services on the functional outcomes reviewed in this paper.
The impact of medications and outpatient services on functional outcomes
As noted previously, individuals diagnosed with schizophrenia have higher mortality rates and health issues, significant cognitive deficits and functional capacity limitations, greater involvement in the criminal justice system, increased risk of being both the victims and perpetrators of violence, are overly represented among the homeless, and report lower levels of QoL. While there is no simple solution, there are some consistent interventions that have been shown to improve the functional outcomes reviewed in this paper.
Correll and colleagues showed that prescribing antipsychotic medications can protect against all-cause mortality in individuals diagnosed with schizophrenia.Reference Correll, Solmi and Croatto 8 Moreover, the second-generation antipsychotics (SGAs), long-acting injectables (LAIs), clozapine, and SGA–LAIs offered the most significant reductions in mortality rates.Reference Correll, Solmi and Croatto 8 The impact of LAIs and clozapine has been shown to improve continued treatment with cardiometabolic medications, such as statins, antidiabetic, and hypertensions medications.Reference Solmi, Tiihonen, Lähteenvuo, Tanskanen, Correll and Taipale 32 Moreover, LAIs have been shown to improve medication adherence, relapse prevention, and psychotic symptoms control, as well as improved cognitive functioning in first-episode schizophrenia patients.Reference Subotnik, Casaus and Ventura 33
Even the simple possession of consistent medication prescriptions, especially during the first 90 d post discharge, as well as routine outpatient services, offers one of the most significant protections against reincarceration for adults with schizophrenia.Reference Van Dorn, Desmarais, Petrila, Haynes and Singh 14 High medication possession, which was defined as having medication to cover 80% or more of the days in a 30-d period, was associated with a reduction in arrest.Reference Van Dorn, Desmarais, Petrila, Haynes and Singh 14 Interestingly, the reduction in arrests for medication possession was not observed for individuals who had medication possession for less than 90 d post discharge, indicating that consistent medication possession is critical for the observed reductions in arrests.Reference Van Dorn, Desmarais, Petrila, Haynes and Singh 14 Also, monthly routine outpatient services were associated with the reduction of misdemeanor arrests.Reference Van Dorn, Desmarais, Petrila, Haynes and Singh 14 Those who were arrested utilized systems (eg, psychiatric hospitalizations and emergency services) associated with higher acute care costs as compared to those who were not arrested; those who were not arrested had higher outpatient and pharmacological costs, which were still considerably lower than the more expensive acute care costs.Reference Van Dorn, Desmarais, Petrila, Haynes and Singh 14 Economic modeling of the Van Dorn and colleagues’Reference Van Dorn, Desmarais, Petrila, Haynes and Singh 14 study shows that the potential fiscal impact to state government, with a hypothetical 20% increase of antipsychotic medication upon release from incarceration, could lead to direct cost savings of $1.7 million over a 3-y period.Reference Lin, Muser, Munsell, Benson and Menzin 34 Thus, consistent medication possession among this population could result in direct cost savings for local and state governments by improving efficiency and reducing unnecessary expenditures.
Van Dorn and colleagues have demonstrated that violence perpetration was a positive indicator of both itself and victimization, drug use, and affective symptoms, while cognitive disorganization was associated with a decrease in violence perpetration.Reference Van Dorn, Grimm, Desmarais, Tueller, Johnson and Swartz 35 Violent victimization was positively indicated by itself and violence perpetration, as well as affective symptoms and alcohol.Reference Van Dorn, Grimm, Desmarais, Tueller, Johnson and Swartz 35 Their study also showed that violent victimization, alcohol or drug use, and inpatient hospitalization were associated with an increased likelihood of homelessness. The findings of this study support the use of outpatient services (eg, trauma informed therapy and cognitive behavioral therapy) and pharmacological interventions that target the affective symptoms associated with schizophrenia, which can reduce events of violence.Reference Van Dorn, Grimm, Desmarais, Tueller, Johnson and Swartz 35 Similarly, combined pharmacological and psychotherapeutic treatment, well-managed medication side effects, and integration into community programs (as opposed to being institutionalized) have been associated with higher subjective reports of QoL.Reference Bobes, Garcia-Portilla, Bascaran, Saiz and Bouzoño 23
Conclusion
While symptom identification and monitoring are critical for diagnostic clarification and treatment, the findings of this brief literature review highlight the critical need to incorporate functional outcomes associated with schizophrenia that extend beyond just symptom management and reduction. The key point of these studies is that consistent matched treatment that includes both pharmacological and outpatient services has been shown to improve all functional outcomes. Consistent matched treatment and outpatient services that prioritizes improved medication adherence with SGAs, clozapine, and LAIs can significantly improve mortality rates (most notably related to suicide and injury), everyday functioning, and QoL in individuals disabled by schizophrenia. Clinicians are strongly encouraged to incorporate brief health measure screenings to identify illness risk and reduce mortality. Furthermore, consistent matched treatment and outpatient services that incorporate substance abuse screenings and treatment, trauma informed therapy, cognitive behavioral therapy, and pharmacological treatment that targets both psychosis and affective symptoms have been shown to reduce arrests, violence (both perpetration and victimization) rates, and homelessness. And finally, consistent matched treatment and outpatient services that include neurocognitive and social cognitive training have been shown to improve cognitive and functional capacity dimensions, which are essential for managing everyday life. Better community integration, managed symptoms, improved health, and purposeful living have been shown to improve QoL. Clinicians, researchers, and policymakers need to broaden their conceptualizations of “outcomes” to go beyond the management of psychosis symptomatology. This paper presents a conceptual framework for advancing more holistic, real-world functional outcomes that promote enhanced community integration and safety, as well as meaningful life experiences for individuals diagnosed with schizophrenia.
Author contribution
Conceptualization: S.E.E.
Open access
