Kidney Stones May Increase Women’s CHD Risk

A history of kidney stones is associated with an increased risk of coronary heart disease (CHD) in women but not in men, reports a study in the Journal of the American Medical Association.

The analysis included data on a combined group of more than 45,000 men and 196,000 women from three prospective follow-up studies of health care professionals, all initially free of CHD. A history of kidney stones was analyzed as a risk factor for CHD, defined as fatal or nonfatal myocardial infarction (MI) or coronary revascularization.

Overall, 8.1 percent of participants had a history of kidney stones. At follow-up times of up to 24 years in men and 18 years in women, there were nearly 17,000 incident cases of CHD.

A history of kidney stones was associated with a higher risk of CHD in women. The CHD incidence rate was 754 versus 514 per 100,000 in one cohort of female registered nurses and 144 versus 55 per 100,000 person-years in a second cohort. In multivariable analyses, the hazard ratios for CHD associated with kidney stones were 1.18 and 1.48, respectively.

For women, kidney stones were associated with the individual outcomes of fatal and nonfatal MI and revascularization. Men showed no association between kidney stones and CHD risk.

The prevalence of kidney stones appears to be increasing. Some previous studies have found an increased risk of MI among patients with a history of kidney stones.

The new analysis supports the association between kidney stones and CHD in women, although not in men. The authors discuss possible explanations, including cardiovascular risk factors, shared dietary risks, and deterioration of kidney function related to kidney stones. Further study will be needed to evaluate these mechanisms and to determine whether an association is truly sex specific [Ferraro PM, et al. History of kidney stones and the risk of coronary heart disease. JAMA 2013; 310:408–415].