Sleep Duration and Blood Pressure During Sleep

The purpose of this study is to examine the impact that sleep duration has on blood pressure (BP) levels during sleep. The investigator will examine the effect of an 8-week sleep hygiene/extension intervention vs. control on sleep BP.

Short sleep duration (SSD), defined as sleeping less than 7 hours per night, affects over 33% of US adults and is associated with increased mortality. SSD is a modifiable risk factor for obesity, type 2 diabetes, and HTN. Cross-sectional studies have demonstrated that SSD is associated with higher sleep BP levels. SSD is also associated with non-dipping BP which is primarily explained by higher sleep BP levels. However, many of the cross-sectional studies have included adolescent participants or have not used reference standard measures of sleep duration such as wrist actigraphy. Manipulating sleep duration experimentally through sleep restriction or deprivation is associated with higher 24-hour and sleep BP levels. In contrast, there is scarce data on the effect of sleep extension on sleep BP levels among adults with SSD. Eligible community individuals with short sleep duration will be randomized to sleep extension vs. control using 24-hour ambulatory blood pressure monitoring (ABPM) and actigraphy in the naturalistic environment. Individuals will be assessed throughout the study using questionnaires, activity monitoring via a Fitbit device (for 8 weeks), blood pressure monitoring using a 24-hour ABPM device, and heart rate variability monitoring for 24-hours.

Participants will be randomized in a 1:1 ratio to each arm by a computer-generated random allocation sequence. All study investigators and outcome assessors will be blinded to group assignment and will not have access to the randomization sequence. The Educational Research Coordinator who will deliver the educational sessions will be unblinded to treatment arm but will not be involved in collecting study measures or data analyses.

Participants with short sleep duration will receive a 60-minute educational session on sleep hygiene/extension. Over an 8-week period, participants will receive weekly phone or Zoom video calls from the Educational Research Coordinator to review additional materials including handouts and/or complete questionnaires about sleep. Participants will undergo sleep tracking/monitoring during the 8-week period, and repeat BP/heart rate monitoring for 24 hours after the 8-week period.

Participants with short sleep duration will receive a 60-minute educational session on sleep physiology. Over an 8-week period, participants will receive weekly phone or Zoom video calls from the Educational Research Coordinator to review additional materials including handouts. Participants will undergo sleep tracking/monitoring during the 8-week period, and repeat BP/heart rate monitoring for 24 hours after the 8-week period.

The 60-minute sleep hygiene/extension educational session include the following: This session will consist of questionnaires, handouts, videos, and a discussion. Topic examples include information on establishing a comfortable sleep environment, including strategies on how to extend sleep duration by a maximum of 1 hour over the duration of the 8-week trial for an average of 7.5 minutes per week, not to exceed 15 minutes per week. Participants will also receive educational brochures and a sleep diary.

The 60-minute educational session will address sleep physiology but not sleep hygiene. This session will consist of questionnaires, handouts, videos, and a discussion. Participants will receive an educational brochure.

Mean of valid BP readings during the sleep period on 24-hour ambulatory blood pressure monitor will be calculated to obtain mean sleep systolic BP (mmHg) at baseline and 8 weeks. The change in mean sleep systolic BP from baseline to follow-up (baseline minus follow-up sleep systolic BP) will be calculated and compared across randomization arms.

Mean of valid BP readings during the sleep period on 24-hour ambulatory blood pressure monitor will be calculated to obtain mean sleep diastolic BP (mmHg) at baseline and 8 weeks. The change in mean sleep diastolic BP from baseline to follow-up (baseline minus follow-up sleep diastolic BP) will be calculated and compared across randomization arms.

Mean of valid BP readings during the awake period on 24-hour ambulatory blood pressure monitor will be calculated to obtain mean awake systolic BP (mmHg) at baseline and 8 weeks.

Mean of valid BP readings during the awake period on 24-hour ambulatory blood pressure monitor will be calculated to obtain mean awake diastolic BP (mmHg) at baseline and 8 weeks.

Mean of valid BP readings during the awake period on 24-hour ambulatory blood pressure monitor will be calculated to obtain mean awake 24-hour systolic BP (mmHg) at baseline and 8 weeks.

Mean of valid BP readings during the awake period on 24-hour ambulatory blood pressure monitor will be calculated to obtain mean awake 24-hour diastolic BP (mmHg) at baseline and 8 weeks.

24-hour high frequency heart rate variability will be estimated from R-R interval data from the Cardio SOLO device at baseline and 8 weeks and compared across randomization arms.

This is to measure if the intervention (sleep hygiene/extension) would increase mean sleep duration for participants randomized to sleep hygiene/extension, actigraphy-derived sleep duration will be used to evaluate the intervention. Actigraphy-derived mean sleep duration will be calculated daily as the total time between the sleep and awake period as defined on the Fitbit device in number of hours.

Inclusion Criteria: English speaking adults Age 18 and older Sleep duration < 7 hours per night as assessed via daily self-report of sleep hours Exclusion Criteria: Inability to read or write in English Pregnant or plans to get pregnant within study period Arm circumference >50 cm Lymphedema of the arm or unable to wear ABPM device for 24 hours or wrist actigraphy for 8 weeks End-stage renal disease (ESRD) on dialysis Unreliable internet or phone/text access High risk of Obstructive Sleep Apnea (OSA) (using the Berlin Questionnaire or diagnosis of OSA or use continuous positive airway pressure device) High risk of insomnia (using the Insomnia Severity Index), or a known prior history of insomnia, and/or use of prescription sleep aides High risk of depression (using the Patient Health Questionnaire Depression Scale: PHQ-8) Perimenopausal women who have hot flashes (using the Menopause Rating Scale (MRS) questionnaire, administered only to females age 45-65) Plan to travel out of state and/or internationally during the study period