Abstract
BACKGROUND: Observationally, family and social support are important for optimal diabetes self-management; however, interventions targeting family/social support have not consistently been effective. A novel, diabetes-specific family functioning typology offers the opportunity to classify types of baseline family functioning to determine for whom family interventions may be effective. PURPOSE: We examined the effects of an intervention by baseline type of family functioning post hoc, to inform differential benefit from interventions. METHODS: Participants were randomized to enhanced treatment as usual or a 9-month, mobile phone-delivered, family-focused, self-care support intervention. Adults with type 2 diabetes (N = 318) who participated in the randomized clinical trial (RCT) and provided baseline data were included. We determined participants' diabetes-specific family functioning types at baseline using a validated, survey-administered, typology assessment tool. We investigated the associations between type and engagement (eg, attending coaching sessions and responding to text messages) and psychosocial (eg, well-being and diabetes distress) and glycemic outcomes at mid- and post-treatment. RESULTS: Despite overall high engagement, there was variability across types in engagement and effects. WantMoreInvolvement benefited the most; Satisfied withLowInvolvement showed early improvements that waned; Collaborative &Helpful were highly engaged but derived minimal benefits from the intervention; and CriticallyInvolved benefitted the least and may have experienced some harm. CONCLUSIONS: We demonstrated the utility of a novel diabetes-specific family functioning typology to explain variability in response to a family-focused intervention. Findings from this work answer the calls for systems-level consideration in precision behavioral medicine and drive hypothesis generation for future, tailored interventions. REGISTRATION: The larger RCT is registered with ClinicalTrials.gov (NCT04347291).