Cardiometabolic disease among sexual minority individuals in the United States is underexplored, despite being the leading cause of death for all adults across populations [1], [2], [3]. The limited research that exists focuses on individual-level influences, and there is a dearth of research using objective measures. Beyond the individual level, intimate partners may be an especially important influence on cardiometabolic health for sexual minority couples. Different-sex couples are known to influence each other’s cardiometabolic risk, including hypertension and overweight/obesity [4], however, the role of partners on cardiometabolic risk factors is underexplored in same-sex relationships [5], [6], [7].

Growing literature demonstrates the benefits of couple-based interventions in chronic conditions, including cardiometabolic risk and disease management [8], [9], [10]. Compared to individual-level engagement, adherence to cardiac risk reduction strategies is maintained when both partners in a couple are engaged [11]. Similarly, lifestyle-related risk factor modification for secondary cardiovascular disease prevention is improved in patients with a participating partner [12], [13]. However, most studies of such couple-level interventions have either focused solely on different-sex couples, or have not clearly distinguished between different-sex and same-sex couples. Interventions which identify and target the unique dyadic influences in intimate same-sex partnerships, focused on cardiometabolic health, are lacking.

There are several reasons to believe that partner influences on cardiometabolic risk may be especially important in sexual minority relationships, necessitating interventions tailored specifically towards intimate partnerships in this population. First, available evidence suggests that concordance of self-reported health may be higher in same-sex than different-sex partnerships [5]. Second, sexual minority individuals may have inadequate support from families and communities of origin due to stigma and discrimination, making chosen family members (including partners) a particularly salient source of support and influence [14], [15]. Third, an integrated model of Minority Stress and Stress Proliferation postulates that shared experiences with homophobia and other discrimination adversely impact the health of same-sex couples, beyond individual-level effects [16]. Despite these indications that partners are a critical influence on health, existing studies of same-sex couples and health have focused mostly on communicable disease treatment and prevention (including HIV), and relationship dynamics [17], [18], [19], [20], [21], [22].

As a first step towards addressing these gaps in the literature, this manuscript answers two questions. First, what is the concordance of cardiometabolic risk factors, as measured by objective anthropometric measurements (weight, height, blood pressure), among middle-aged and older same-sex couples in the United States? Second, what data are currently available, and required in the future, to characterize cardiometabolic risk concordance among same-sex couples?