The impact of side-effects of antipsychotic agents on life satisfaction of schizophrenia patients: a naturalistic study
Introduction
Antipsychotic medications have a wide range of adverse effects that may cause physical and psychological harm to schizophrenic patients. Moreover, adverse events are considered a major source of subjective discomfort, and non-compliance with treatment (Fenton et al., 1997, Lader, 1999, Cabeza et al., 2000). Findings concerning the effects of adverse events on quality of life (QOL) of psychiatric patients are controversial: some studies have found negative correlation of subjective QOL with dosage of antipsychotics and number of side-effects (Kemmler et al., 1994, Packer et al., 1997, Voruganti et al., 1997, Young et al., 1998), while others did not (Browne et al., 1966, Larsen and Gerlach, 1996, Gerlach and Larsen, 1999). Empirical comparison data on the effects of conventional and atypical antipsychotics on QOL ratings are also equivocal. Findings of better QOL outcomes for patients receiving atypical versus conventional agents have been reported (Franz et al., 1997, Rosenheck et al., 1997, Awad and Voruganti, 1999, Revicki et al., 1999), but not replicated (Essock et al., 1996, Awad et al., 1997b, Tempier and Pawliuk, 2001). This inconsistency could result from the fact that clinicians focus on observable side-effects, while patients tend to report more subjective adverse events (akathisia, dysphoric mood, or emotional indifference) (Gerlach and Larsen, 1999). Another possibility is inconsistent use of observer-based versus self-report QOL measurements (Voruganti et al., 2000). Finally, the contribution of adverse events to QOL appraisal may be merely overestimated, as this body of research tends to lack controls for confounding variables. However as previous studies found adverse effects to be negatively associated with subjective QOL of schizophrenia patients, it is unclear if the relationships are spurious.
The concept of quality of life is distinct from health, though related to it. Most conceptualizations of health related quality of life include the dimensions of physical functioning, social functioning, role functioning, mental health and general health perceptions with important concepts such as energy, fatigue, pain, and cognitive functioning included in these broader categories (Wilson and Cleary, 1995). These physical, psychological, and social domains of health, are seen as distinct areas that are influenced by a person’s experiences, beliefs, expectations, and perceptions (Testa and Simonson, 1996). While there is no universal operational definition of QOL, most researchers agree that patients’ statements on satisfaction with major life domains of daily functioning are relevant indicators of subjective QOL (WHOQOL Group, 1995, Lehman, 1996, Priebe et al., 2000). Awad (1992) proposed a conceptual model focusing on the impact of antipsychotic medication on the subjective QOL of schizophrenic patients. In his model, QOL is viewed as one’s perception of the outcome of an interaction between psychotic symptom severity, side-effects including subjective responses to antipsychotics, and the level of psychosocial performance. Multiple regression analysis showed that severity of symptoms, subjective distress caused by akathisia and neuroleptic dysphoria accounted for nearly half of the variance in subjective quality of life scores, while the contribution of psychosocial indicators was negligible (Awad et al., 1997a). This model has limited applicability as it fails to consider many important psychosocial factors potentially affecting QOL, such as self-efficacy, coping devices, and social support.
In this naturalistic survey we sought to evaluate the influence of adverse effects of antipsychotic drugs, severity of clinical symptoms and psychosocial factors on perceived QOL of schizophrenic inpatients in the framework of a distress/protection model. The distress/protection model of QOL includes dimensions of satisfaction with physical health, subjective feelings, leisure activities, social relationships, general activities, medication, and involves measures of psychopathology, adverse events and concomitant distress, personal and social resources (Ritsner et al., 2000). The specific contribution of antipsychotic adverse effects to the QOL appraisal in this model was not previously explored.
Section snippets
Experimental procedures
This study is part of a larger project evaluating QOL of hospitalized patients with severe mental disorders (SMD): schizophrenia, schizoaffective, major depression, and bipolar disorders (Sha’ar Menashe Longitudinal Study of Quality of Life; SMLS-QOL). Data collection, sociodemographic and clinical profiles of the participants were reported in detail elsewhere (Ritsner et al., 2000). Briefly, a list of all SMD patients consecutively admitted to closed, open, and rehabilitation wards prior to
Adverse events
A total of 138 patients (85.7% of the entire sample), revealed one or more adverse events, more likely to be mental (80.1%, n=129) than somatic in nature (63.4%, n=102; χ2=10.4, df 1,161, P<0.01). No significant correlation between DSAS indices and length of current hospitalization, dosage of antipsychotics, as well as adjunctive antidepressants, anxiolytics or mood stabilizers was found.
Patients with established adverse events reported significantly less satisfaction with life domains of
Discussion
The primary strength of this naturalistic study is that data were collected from a systematically ascertained sample of schizophrenia patients from various hospital settings, representing routine hospital practice. Unlike earlier studies (Essock et al., 1996, Awad et al., 1997a, Franz et al., 1997, Awad and Voruganti, 1999, Revicki et al., 1999, Gerlach and Larsen, 1999), we investigated the influence of side-effects, combined with clinical and several psychosocial factors on subjective QOL
Acknowledgements
We wish to thank O. Rivkin, MD, Y. Nechamkin, MD, E. Bistrov, MD, and our research assistant M. Z’ada for their assistance in data collection, and R. Kurs, BA for editing the manuscript. This study was partly supported by the Ministry of Absorption, State of Israel.
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