Objective: The aims of this study were to test for a diurnal pattern in hot flashes in a multiethnic population living in a hot, humid environment and to examine the rates of concordance between objective and subjective measures of hot flashes using ambulatory and laboratory measures.
Methods: Study participants aged 45 to 55 years were recruited from the general population of Hilo, HI. Women wore a Biolog hot flash monitor (UFI, Morro Bay, CA), kept a diary for 24 hours, and also participated in 3-hour laboratory measures (n = 199). Diurnal patterns were assessed using polynomial regression. For each woman, objectively recorded hot flashes that matched subjective experience were treated as true-positive readings. Subjective hot flashes were considered the standard for computing false-positive and false-negative readings. True-positive, false-positive, and false-negative readings were compared across ethnic groups by χ2 analyses.
Results: Frequencies of sternal, nuchal, and subjective hot flashes peaked at 1500 ± 1 hours with no difference by ethnicity. Laboratory results supported the pattern seen in ambulatory monitoring. Sternal and nuchal monitoring showed the same frequency of true-positive measures, but nonsternal electrodes picked up more false-positive readings. Laboratory monitoring showed very low frequencies of false negatives. There were no ethnic differences in the frequency of true-positive or false-positive measures. Women of European descent were more likely to report hot flashes that were not objectively demonstrated (false-negative measures).
Conclusions: The diurnal pattern and peak in hot flash occurrence in the hot humid environment of Hilo were similar to results from more temperate environments. Lack of variation in sternal versus nonsternal measures and in true-positive measures across ethnicities suggests no appreciable effect of population variation in sweating patterns.
In the hot and humid environment of Hilo, HI, the diurnal peak in hot flashes occurred at 15:00 ± 1 hour with no difference by ethnicity. Sternal and nuchal monitoring showed the same frequency of true positive measures, and there were no ethnic differences in the frequency of true positive measures, suggesting no appreciable effect of population variation in sweating patterns on hot flash measures.
From the Departments of 1Anthropology, 2Mathematics and Statistics, University of Massachusetts Amherst, Amherst, MA; and 3Department of Anthropology, University of Hawaii at Hilo, Hilo, HI.
Received August 26, 2009; revised and accepted October 26, 2009.
Funding/support: This work was supported by National Institutes of Health Grant S06-GM08073-34.
Financial disclosure/conflicts of interest: None reported.
Address correspondence to: Lynnette Leidy Sievert, PhD, Department of Anthropology, University of Massachusetts Amherst, Machmer Hall, 240 Hicks Way, Amherst, MA 01003-9278. E-mail: firstname.lastname@example.org