To the best of our knowledge, this is the first randomized controlled study exploring the effect of a community pharmacist’s intervention on the QoL of older adult patients receiving warfarin therapy in rural areas. In the present study, a pharmacist’s intervention had a positive impact on the QoL of the patients on warfarin therapy.
As this is the first study of its kind, there are no previous studies that would allow direct comparison of findings. As such, we discuss our findings in the context of previous studies that involved a different population or setting. For example, a meta-analysis performed by Mohammed et al., which included 48 studies, found that pharmaceutical care interventions can significantly improve at least one domain of health-related QoL [11]. However, only one of the included studies involved patients on anticoagulants. This study was performed in tertiary care setting and compared pharmacist-led warfarin self-management program with standard care at an anticoagulation clinic, showing benefits of the pharmacist-led program [12].
Overall, at the end of the study, we observed improved QoL and satisfaction in the intervention group across all 3 domains of the questionnaire. Our results are consistent with data published by Elewa et al. [13] In their nonrandomized study, the overall QoL score of patients attending an anticoagulation clinic run by pharmacists in Qatar was 63, which is comparable to the score achieved in the intervention group in our study. It should be noted that the DASS questionnaire used in their study was modified in a cultural adaptation process, and one question was left out (regarding consumption of alcoholic beverage), bringing the questionnaire to 24 items.
In an observational study, Hasan et al. found that the QoL of patients taking warfarin over 1 year declined significantly [5], which might not be surprising given the side effects, periodic monitoring that entails discomfort for the patient, and other therapy-associated limitations. Furthermore, Matchar et al. have shown that the QoL increases when the patient is less dependent on a visit to the doctor or laboratory and can monitor the INR at home, using a portable device (known as point-of-care testing [POCT]) [14]. The same authors have also emphasized that such testing does not affect clinical outcomes or mortality. Similarly, Sølvik et al. [15] concluded that QoL was improved in patients who self-control INR and self-titrate warfarin doses. According to these authors, patients who switch from conventional care to the self-care model after 2 years have a significantly higher QoL, probably because they are less dependent on going to the doctor. In contrast, Carris et al. found that anticoagulation satisfaction following extended interval monitoring, as measured by the DASS questionnaire, did not change or may have marginally worsened after an extended interval follow up, which was contrary to expectations [16]. The authors suggest that less frequent feedback and patient-provider interaction might have resulted in reduced patient perception of benefit from anticoagulation and reduced self-management activities [16]. We agree with the last observation and believe that intervention group in our study benefited from more frequent patient-provider interaction.
Our secondary aim was to establish factors predictive of QoL. Among 9 analyzed variables, only pharmacist intervention and experience of ADRs predicted QoL. Experience of the ADRs was identified as the strongest predictor for lower QoL. Hemorrhagic events negatively influenced QoL in a previous study by Lancaster et al. [17]. In contrast, they did not influence QoL in a study by Casais et al. [18]. Although other studies have reported different findings on the association between ADRs and QoL, based on our results, we recommend focusing on the management of ADRs to increase QoL of patients on warfarin. As most of the ADRs recorded in our sample were not serious (i.e. bruising), we believe that counseling patients on minor bleeding signs would increase patients’ overall satisfaction with warfarin therapy.
Concurrently, other studies have identified socio-demographic factors that influence QoL in patients on warfarin [5, 19]. Although Hasan et al. have shown that men score higher [5], in our study this effect has not been confirmed. Neither years played a role unlike other studies [5, 19], probably because our sample was more homogeneous, that is, it included only elderly people. Almeida et al. have shown that, in a cohort of Brazilian patients who were 67 years old, QoL was influenced by experience of side effects, age, comorbidities, drug interactions, level of education, and duration of treatment [19].
We believe that our results significantly contribute to the QoL and pharmaceutical care research. Measuring humanistic outcomes in the form of health-related QoL, in addition to clinical and economic outcomes, provides a comprehensive picture of the impact of a healthcare intervention [20]. Improving or maintaining patients’ QoL is a fundamental goal of pharmaceutical care services [11]. Well-known definitions of pharmaceutical care by Hepler and Strand, and later by Cipole et al., stress the importance of QoL in pharmaceutical care stating that pharmaceutical care is the responsible provision of drug therapy for the purpose of achieving definite outcomes that improve and maintain a patient’s QoL [21, 22].
Depending on a country’s development, rural areas might face difficulties in providing quality healthcare and clinical pharmacist services, as documented by Patterson et al. in a sample of more than 3 million patients [23]. Warfarin patients require frequent visits to the laboratory and doctor, which can be difficult in a rural context. Even in well-developed countries and health systems, such as the United States, in urban areas, patients with atrial fibrillation received warfarin more often than did patients in rural areas, despite comparable risk of stroke [24]. A large study by Rose et al., involving 56,490 older patients, showed that there was a loss to follow-up for such patients and that they did not engage with regular laboratory monitoring, while the risk of loss to follow-up was associated with race, poverty, dementia, depression, and remoteness [25]. The present study highlights that community pharmacists are an important factor to overcoming barriers to care experienced by some warfarin patients.
These observations have important clinical implications for rural regions and are especially applicable in countries where pharmacists-managed anticoagulation monitoring services are not common. Patients living in socially deprived regions with restricted access to healthcare facilities and who need support with their warfarin therapy could benefit from a community pharmacist-managed service.
Limitations
Since the QoL instrument was not applied before and after the pharmacists’ intervention, we were not able to observe the magnitude or the direction of change in the QoL. Nevertheless, the randomized controlled design of our study allowed observing a positive effect in the intervention group. This aspect notwithstanding, our results are applicable to a specific population and cannot be generalized. The isolation of these patients, low level of education, and increased availability of healthcare could have created a stronger positive impact of the pharmacy-based interventions in the study patients.