Shedding light on the association between social support and adherence in hypertension: a comment on Magrin et Al.

Improving adherence to medical recommendations among patients with chronic conditions such as hypertension remains one of the most important yet intractable problems in healthcare. Studies repeatedly demonstrate that because of inadequate adherence, there are consistent and clinically significant gaps between treatment efficacy in controlled trials and health outcomes in real-world populations. Psychosocial factors have long been implicated in medication non-adherence, and social support in particular has received extensive attention, resulting in a vast multidisciplinary literature that is challenging to navigate. It is therefore heartening to see the meta-analyses conducted by Magrin and colleagues [1] in this issue, in which the authors evaluate the role of social support in adherence among people diagnosed with hypertension. In this meticulously conducted study, the authors found that functional, but not structural, support was associated with adherence. In other words, the mere presence of a spouse or other person in the patients’ social network was not in and of itself sufficient to improve adherence; rather, such an individual had to be actively involved in disease management. This was true for adherence to medications, as well as to recommendations about diet, physical activity, and smoking. As the authors note, these findings mirror those of the often-cited study by DiMatteo et al. [2] but within a hypertensive population. These authors succeeded in synthesizing a vast and unwieldy literature on the role of social support for adherence in hypertension and make an important new contribution by providing clear evidence of the value of functional support. The meta-analysis also highlights key limitations in existing studies and, in doing so, provides direction to further research. Foremost, the majority of the studies so far have been crosssectional, suggesting an urgent need for prospective observational studies that can help tease apart the causal link between functional support and adherence. There is also a strong need to operationalize functional support. As the authors noted, structural support was consistently defined as the presence of a spouse or significant other. However, functional support included emotional support, practical (i.e., instrumental) support, and educational or information-based support. Prospective, observational studies may allow us to compare the unique contributions of each of these subtypes. Finally, the mechanisms through which functional support enhances adherence deserve closer examination. The possible mediators of the relationship include depression, literacy, and division of responsibilities, but warrant closer examination. The meta-analysis highlights other limitations of the current literature. Social support should be examined not as a static construct but one that changes over time and one that differentially interacts with patient characteristics such as loneliness and depression. Historically, social support has been measured by patients’ perceived social support, which may differ from the perception of the social support provider or more objective criteria. This discrepancy may be an important marker of stress in the patient-supporter relationship. It is also time to gather more data directly from social support providers (caregivers) to provide a fuller picture of how social support enhances adherence. For people with chronic conditions such as dementia, heart failure, and diabetes, engaging both cohabitating caregivers and non-cohabitating caregivers has been shown to improve adherence by giving them R. B. Trivedi (*) Center for Innovation to Implementation, VA Palo Alto Health Care System, Department of Psychiatry and Behavioral Sciences, Stanford University, 795 Willow Rd Bldg 324, Menlo Park, CA 94025, USA e-mail: ranak.trivedi@va.gov