Publications

STUDY OBJECTIVES

To compare causes of sleep disturbance and to compare self-reported sleep duration among groups of late premenopausal women and early perimenopausal women.

METHODS

In a longitudinal study of a community-based sample of healthy women 40 to 50 years of age, menstrual cycle and symptom data were collected every 2 months; anthropometric measures, a urine sample for follicle stimulating hormone (FSH), and the Pittsburgh Sleep Quality Index (PSQI) measures were collected every 6 months.

RESULTS

At 12 to 18 months, 206 women remained premenopausal and 69 women became perimenopausal. Poor sleep quality (PSQI score > 5) was experienced by 42% of the total cohort. Awakening to use the bathroom was the most frequent reason (81%) for sleep disturbance in the entire cohort, followed by feeling too hot (26%). However, premenopausal women were significantly more likely to awaken to use the bathroom than perimenopausal women ( = .047), and perimenopausal women were more likely than premenopausal women to awaken because of feeling too hot ( = .002). Women in early perimenopause reported shorter sleep duration ( = .007) and worse sleep quality ( = .05) than premenopausal women of similar age.

CONCLUSIONS

Sleep disturbance is a significant issue for midlife women regardless of age or reproductive stage. Identification of salient factors that disrupt sleep, such as nocturia prior to menopausal transition or feeling too hot early in menopausal transition, will provide direction for developing tailored intervention strategies to improve sleep and quality of life.

COMMENTARY

A commentary on this article appears in this issue on page 1095.

Optogenetics is a transformative technology based on light-sensitive microbial proteins, known as opsins, that enable precise modulation of neuronal activity with pulsed radiant energy. Optogenetics has been proposed as a means to improve auditory implant outcomes by reducing channel interaction and increasing electrode density, but the introduction of opsins into cochlear spiral ganglion neurons (SGNs) in vivo has been challenging. Here we test opsin delivery using a synthetically developed ancestral adeno-associated virus (AAV) vector called Anc80L65. Wild-type C57BL/6 mouse pups were injected via the round window of cochlea with Anc80L65 carrying opsin Chronos under the control of a CAG promoter. Following an incubation of 6-22 weeks, pulsed blue light was delivered to cochlear SGNs via a cochleosotomy approach and flexible optical fiber. Optically evoked auditory brainstem responses (oABRs) and multiunit activity in inferior colliculus (IC) were observed. Post-experiment cochlear histology demonstrated opsin expression in SGNs (mean = 74%), with an even distribution of opsin along the cochlear basal/apical gradient. This study is the first to describe robust SGN transduction, opsin expression, and optically evoked auditory electrophysiology in neonatal mice. Ultimately, this work may provide the basis for a new generation of cochlear implant based on light.