Does compensatory hyperparathyroidism predispose to ischemic stroke?

BACKGROUND

Parathyroid hormone (PTH) is vasoactive, and the endothelium is one of the target tissues of this hormone. Hyperparathyroidism is frequently associated with hypertension.

OBJECTIVE

To determine if hyperparathyroidism, which develops particularly in elderly women as a compensatory mechanism to osteoporosis, may be a risk factor for ischemic stroke.

METHODS

Serum PTH levels and bone mineral density (BMD) in 107 elderly patients with ischemic stroke (>or=65 years old) were assessed on the day of onset. The control group consisted of 107 healthy volunteers matched for age and sex.

RESULTS

BMD was significantly lower and serum PTH higher in female stroke patients than in control subjects; there was a negative correlation between these two measurements. One-third of the female stroke patients had a serum PTH level higher than the mean + 2 SD of the control subjects (high PTH group), and the interval between menopause and the stroke was significantly longer in the high PTH group than in the normal PTH group. Multiple logistic analyses revealed hypertension and ischemic heart disease were more prevalent in the high PTH group. BMD and PTH were normal in male stroke patients.

CONCLUSION

High serum PTH level may be associated with high incidence of ischemic stroke in women, possibly through the increased incidence of hypertension.