Type 2 diabetes, arguably the world's fastest-growing chronic condition, really has it out for women, says a new study. Compared with men with diabetes, diabetic women are 44% more likely to go on to suffer coronary heart disease, which is the leading cause of death for men and women alike in the United States.
Women with diabetes were also 44% more likely than men with the condition to die of heart disease, the researchers found.
The study, published Thursday in the European journal Diabetologia, follows the recent publication in the Lancet of research by the same authors. That earlier study found that a woman with diabetes is on average 25% more likely to suffer stroke than a diabetic man.
The striking findings on diabetes' gender discrimination emerge from a new meta-analysis -- an aggregation of findings from separate but similar studies. The authors, a team of epidemiologists from Britain, Australia and Johns Hopkins University in Baltimore, suggest that the stage is most likely set for women's greater risk of heart disease during the prediabetic state. During that period, affected women tend to be fatter than diabetic men, and their risk factors for heart attack -- often unrecognized and untreated by physicians -- are both "chronically elevated" and mounting quickly, the authors said.
They conclude that their findings should mobilize new efforts to identify and treat prediabetes earlier in women. Prediabetes is defined as having blood sugar levels that are above normal but that fall short of the clinical definition of diabetes. But such metabolic abnormality is often accompanied by the appearance of other key risk factors for heart disease, including high blood pressure, a worrisome cholesterol profile and an expanding waist circumference.
Mounting research suggests that long before it arouses clinical concern, a chronic state of elevated blood sugar -- the result of either impaired insulin production or of growing insulin insensitivity in the cells (or both) -- may impair the function of tiny blood vessels throughout the body. And the systemic inflammation that comes with prolonged metabolic impairment may also weaken blood vessels and make heart attacks more likely.
In women, especially those whose metabolic abnormalities fall short of full-blown diabetes, the authors suggested that physicians may be slow to discern the makings of heart disease and to act aggressively to head it off with medication or lifestyle counseling. But they said that undertreatment of women is unlikely, alone, to explain such a chasm between diabetic men and women when it comes to heart disease.
The challenge of heading off diabetes and its ills in women was, coincidentally, the subject of a second study published this week, which underscored the protective effect that exercise can have on overweight or obese women as they head into middle age. Published ahead of print this week by the Journal of Clinical Endocrinology & Metabolism, the new research found that in overweight and obese women around the time of menopause, engaging in high levels of physical activity was the only factor that delayed or prevented the transition from "metabolically healthy" to "at risk" of developing diabetes or cardiovascular disease.
That study also found that in 866 overweight and obese women between the ages of 42 and 52, those who had impaired fasting glucose at the outset, as well as those who were obese to begin with and who gained weight continually through those years, were most likely to shift from the "metabolically healthy" category to the "at risk" category.
The Lancet study culled the findings from 64 separate populations of geographically and ethnically diverse patients -- nearly 900,000 study participants altogether, among whom there were roughly 28,000 cases of coronary heart disease. Men who developed Type 2 diabetes certainly suffered the downstream health consequences of their condition: compared with men without diabetes, they were 2.16 times as likely to develop heart disease.
But for women with diabetes, the odds of developing heart disease were 2.82 times higher than for women without diabetes. After taking into account such factors as smoking, ethnicity and men's generally higher level of coronary heart disease, the researchers concluded that diabetic women's risk of developing -- or dying from -- coronary heart disease was 44% higher than that of their male counterparts.