Social Network Trajectories in Myocardial Infarction Versus Ischemic Stroke

Abstract

Background: Changes in social networks are rarely examined before and after various diseases because of insufficient data. CHS (The Cardiovascular Health Study) offers an opportunity to compare social network trajectories surrounding well-adjudicated myocardial infarction (MI) or stroke events. We tested the hypothesis that social networks will be stable after MI and decrease after stroke.

Methods and results: We examined trajectories of the Lubben Social Network Scale score (LSNS, range 0-50) before and after vascular events over 11 years. The LSNS assesses engagement in family networks, friends' networks, and social supports. We used a linear mixed model with repeated measures and fixed effects to compare the change in social network score before and after events in 395 people with MI and 382 with ischemic stroke. Over a mean of 12.4 years of follow-up for MI and 11.1 years for stroke, we examined an average of 4 social network scores for each participant. We controlled for sociodemographics, baseline cognitive function, and comorbidities. The participants' mean age was 73.5, 51% were women, and 88% were non-Hispanic white. After MI, the social network trajectory remained stable compared with the baseline trajectory (-0.06 points per year, adjusted P=0.2356). After stroke, the social network trajectory declined compared with the baseline trajectory (-0.14 points per year, adjusted P=0.0364).

Conclusions: Social networks remained stable after MI and declined after stroke. This small and persistent decline after adjustment for potential confounders is notable because it deviates from stable network trajectories found in CHS participants and is specific to stroke.

Keywords: epidemiology; myocardial infarction; social environment; social support; stroke.

Figure 1

Flow diagram of study participants. Grayed boxes are participants included in trajectory analysis. Of note, 175 patients had both events (86 had MI after stroke and 89 had stroke after MI) and were included in both trajectory analyses. Confirmed dead were during the mean follow‐up of 12.4 years for MI and 11.1 years for stroke. MI indicates myocardial infarction.

Figure 2

Conceptual depiction of the course of social network scores before and after vascular event. In the analysis, the “Annual change in LSNS score before vascular event”, or baseline trajectory, is compared with 0. The “Difference in LSNS score at time of vascular event” compares the mean scores before and after the vascular event. The “Additional annual change of LSNS score after vascular event” is compared with the baseline trajectory. LSNS indicates Lubben Social Network Scale.

Figure 3

Social network trajectories in MI vs stroke. After MI, social network trajectories remained stable compared with baseline trajectories (−0.06 points per year, adjusted P=0.2356). After stroke, social network trajectories declined compared with baseline trajectories (−0.14 points per year, adjusted P=0.0364). *P<0.05. MI indicates myocardial infarction.