Chilliness: a vasomotor symptom in Japan

To examine the differences between biomedical and Japanese women's concepts of vasomotor symptoms and the relationships between the symptom of chilliness (hieshō) and menopause status, other vasomotor symptoms, and environmental factors such as soy isoflavone intake and exposure in Japan.

Participants were healthy Japanese women, aged 45 to 55, living in Kyoto and Fukushima prefectures, divided into menopausal groups based on menstrual patterns. Women recalled 82 general health symptoms during the previous 2 weeks and collected finger-prick dried blood spots and matched 24-hour dietary records, which were analyzed, respectively, for isoflavone concentration by high-performance liquid chromatography coulometric electrode array detection and for soy isoflavone intake using a Japanese phytochemical database.

An examination of kōnenki (Japanese for climacteric) symptoms suggests that chilliness (hieshō), which was reported by 29.3% of participants compared with a range of 3.0% to 22.1% for hot flushes, constitutes an important vasomotor symptom. Chilliness prevalence differed significantly between premenopausal and other menopausal status groups, with positive correlations with other estrogen-influenced sexual-vasomotor symptoms and negative correlations with isoflavone concentrations. Negative correlations with soy isoflavone intake were also found for sweating, although not for nobose and hoteri (two Japanese terms for hot flush).

Chilliness seems to be a more important vasomotor symptom than hot flushes and sweats in Japanese women and may reflect differing thermoregulatory physiology, possibly influenced by dietary soy.