Three studies investigating quality indicators for the treatment of substance use disorders and comorbidity: continuity of care, treatment need and patient satisfaction

Abstract

It has been suggested that existing standard treatments for substance use disorders do not adequately meet the complex needs of patients with comorbidity (co-occurrence of substance use disorders and mental disorders), thus subjecting patients to suboptimal treatment quality and outcomes. To date, there remains limited knowledge on the quality of treatments currently received by patients with comorbidity at existing services. The overarching aim of this thesis was to investigate three quality indicators in the treatment of substance use disorders and comorbidity: continuity of care, treatment need and patient satisfaction. The objective was to compare the quality of treatment received by patients with and without comorbidity at existing standard treatments, to identify the unique needs of patients with comorbidity, and to provide practical recommendations for future research, service delivery and healthcare policy. The thesis was informed by a concurrent mixed-methods design, which included a series of three research studies. Each contributing study aimed to investigate a different aspect of the overarching thesis aim, and utilised a different methodological approach. The series of studies included a theoretical review of the literature, qualitative study using semi-structured interviews and quantitative study using survey research methods. Continuity of care is considered critical in the treatment of comorbidity; yet there exists little agreement as to its meaning, application and measurement in this treatment context. Similarly, it is unknown whether patients with comorbidity experience poorer continuity of care when compared to patients with single diagnoses, and if improvements to continuity of care are associated with positive outcomes. A systematic search of the literature identified 18 studies (total n=199,442 participants) that investigated continuity of care in the treatment of comorbidity. Continuity of care was found to be variably defined, as both a singular or multidimensional construct. Five core types of continuity emerged as critical in the treatment of this patient group. There was unclear evidence from four studies (total n=1,649 participants) that patients with comorbidity are subject to poorer continuity of care in treatment, when compared to patients with single diagnoses. However, this inconsistent data might be explained the variable measurement of CoC across contributing studies. Some consistent evidence from three studies (total n=1,451 participants) suggested achieving continuity of care improves patient and treatment-related outcomes for this patient group. To date, efforts to assess the quality of available treatments for comorbidity have involved quantitative objective methods. These methods may be considered limited in this context, as they fail to capture the quality of care received by patients. In addition, there is a common belief that patients with comorbidity are less satisfied with standard treatments when compared to patients with single diagnoses. However, studies conducted to date have failed to control for a number of variables which have shown importance in single diagnoses samples. A series of two studies were designed to address these aforementioned gaps in the literature. A qualitative study was designed to explore patients’ perceptions of treatment for alcohol use disorders, in relation to the quality indicators: continuity of care, treatment need and patient satisfaction. Responses from semi-structured interviews were examined using the framework method of analysis, and data were compared among patients with (n=15) and without (n=19) comorbidity. Similarly, a cross-sectional quantitative study was conducted using survey methods. This study assessed patient satisfaction with treatment for an alcohol use disorder, in a properly powered sample of 89 patients. Patient satisfaction with treatment was compared among patients with (n=40) and without (n=49) comorbidity. This study also assessed and controlled for treatment setting, treatment readiness, locus of health control and general life satisfaction. Unexpectedly, the series of studies found that patients with comorbidity did not report global deficits in the quality of treatment received, when compared to patients with single disorders. Results produced from the qualitative study found that the major themes relating to continuity of care, treatment need and patient satisfaction were comparable between the groups. Similarly, results from the quantitative study found no differences in patient satisfaction with treatment amongst patients with (M= 25.10, SD = 8.12) and without (M= 25.43, SD= 6.91) comorbidity (p= 0.56), even after controlling for the impact of treatment setting, treatment readiness, locus of health control and general life satisfaction (p= 0.75). In the context of this research, existing standard treatments appear to be suitable in meeting the overall needs of patients with comorbidity. However, an item-by-item comparison of the satisfaction instrument found patients with comorbidity were significantly more dissatisfied with staffs’ understanding of the type of help they wanted in treatment. In addition, data produced from the qualitative study unveiled five basic themes which were uniquely valued by patients with comorbidity, when compared to patients with single diagnoses. Unique themes related to patients’ desire for services to target psychological symptoms through effective medications, psychological treatments, dependable relationships with staff and better coordination of care with services for mental illness. Clinicians, services directors and policy makers are encouraged to consider the suggestions outlined in this research, to improve the treatment of patients with comorbidity in existing services. Improvements to treatment quality might be achieved through staff education and training in the treatment of mental illness, staff selection criteria, better management of staff rostering, improved coordination between addiction and services for mental illness and best practice service provision frameworks. Findings highlight the importance of achieving uniformity in the application and measurement of continuity of care, using multidimensional validated instruments. However, findings produced from this thesis are limited, in that patients included in the sample had been engaged in treatment for at least five days. Thus, findings do not reflect the experiences of patients who were unable to access treatment, those who prematurely dropped out of treatment and patients who had been engaged in lengthy treatment periods. Next, research should look to examine the impact of treatment quality on accessing treatment, ongoing treatment prognosis and long-term outcomes for patients with comorbidity.