The tapes were then reviewed and every statement made by either spouse was scored for its degree of hostility and whether it was submissive or controlling in nature. Comments like "Oh, that's a good idea, let's do it," were considered to be both friendly and submissive. While if someone said, "If it's important to you, I'll do what you want," it was scored as less friendly, but still submissive. In comparison, a statement like, "I'll do what you want if you get off my back," was considered to be both hostile and submissive.
The most negative of the comments like, "You can be so stupid," were scored as both hostile and dominant.
The degree of atherosclerosis in each couple was measured both before the session and two days later with a CT scan.
Interestingly, different forms of quarrelling caused negative effects in each gender. Women who either acted hostile towards their mate or were faced with hostility from him showed more atherosclerosis in the subsequent scan. The husbands, on the other hand, had more hardened plaques on their arteries when there were controlling statements made—either by the men, themselves, or their wives.
These differences, according to Smith, show the inherent gender gap in spousal roles. "Conventional views of harmony versus discord—warm versus hostile interactions—are indeed important for women," he says. "But a different dimension of quality is more important for men, and that has to do with power and control in relationships."
Marital difficulties can be a source of chronic stress, says Smith, who emphasizes that all sources of stress need to be considered when trying to lower the risk of heart disease. Backed up by previous research, which shows the benefit of close relationships for heart health, Smith reminds all couples that no matter how they argue, "a low-quality relationship is a risk factor for cardiovascular disease."