Calculating the dim light melatonin onset: the impact of threshold and sampling rate.
Calculating the dim light melatonin onset: the impact of threshold and sampling rate.
复制标题
DOI：
10.3109/07420528.2011.597531
复制
发表时间：
2011-10
影响因子：
2.8
通讯作者：
Burgess HJ
中科院分区：
文献类型：
--
作者：
Molina TA;Burgess HJ
The dim light melatonin onset (DLMO) is the most reliable circadian phase marker in humans, but the cost of assaying samples is relatively high. Therefore, the authors examined differences between DLMOs calculated from hourly versus half-hourly sampling and differences between DLMOs calculated with two recommended thresholds (a fixed threshold of 3 pg/mL and a variable “3k” threshold equal to the mean plus two standard deviations of the first three low daytime points). The authors calculated these DLMOs from salivary dim light melatonin profiles collected from 122 individuals (64 women) at baseline. DLMOs derived from hourly sampling occurred on average only 6–8 min earlier than the DLMOs derived from half-hourly saliva sampling, and they were highly correlated with each other (r ≥ 0.89, p < .001). However, in up to 19% of cases the DLMO derived from hourly sampling was >30 min from the DLMO derived from half-hourly sampling. The 3 pg/mL threshold produced significantly less variable DLMOs than the 3k threshold. However, the 3k threshold was significantly lower than the 3 pg/mL threshold (p < .001). The DLMOs calculated with the 3k method were significantly earlier (by 22–24 min) than the DLMOs calculated with the 3 pg/mL threshold, regardless of sampling rate. These results suggest that in large research studies and clinical settings, the more affordable and practical option of hourly sampling is adequate for a reasonable estimate of circadian phase. Although the 3 pg/mL fixed threshold is less variable than the 3k threshold, it produces estimates of the DLMO that are further from the initial rise of melatonin.
登录
查看更多内容
影响因子：
4.8
作者：
Smith, Mark R.;Revell, Victoria L.;Eastman, Charmane I.
通讯作者：
Eastman, Charmane I.
影响因子：
3.5
作者：
Benloucif, S;Guico, MJ;Zee, PC
通讯作者：
Zee, PC
影响因子：
2.8
作者：
Portaluppi, Francesco;Smolensky, Michael H.;Touitou, Yvan
通讯作者：
Touitou, Yvan
影响因子：
2.9
作者：
Smith, Mark R.;Cullnan, Erin E.;Eastman, Charmane I.
通讯作者：
Eastman, Charmane I.
影响因子：
10.3
作者：
Revell, VL;Kim, H;Eastman, CI
通讯作者：
Eastman, CI