Table 1.

Unanswered Research Questions on Sleep Disturbances and Blood Pressure^*

Sleep Disturbance Type	Questions
Short Sleep	What are the critical periods of exposure to short sleep during which associations with BP and abnormalities in out-of-office BP are most pronounced? What is the long-term impact of mild sleep deprivation on HTN risk, BP, and 24-h ambulatory patterns? What modifiable factors modulate and mediate the association of short sleep with HTN? What are the racial/ethnic and sex differences in the associations of objectively-assessed sleep and BP across various life stages?
Shift Work	What are the prospective independent and joint associations of shift type and rotational work with HTN incidence and BP abnormalities? What are the effects of acute and long-term repeated exposure to shift work on ambulatory BP? What are the long-term effects of night and rotational shift work on BP control in shift workers with HTN?
Obstructive Sleep Apnea	How do age, sex, daytime somnolence, and antihypertensive medication influence the association of OSA with HTN? What is the short-term and long-term impact of CPAP treatment on clinic BP and 24-h ambulatory BP? What is the impact of CPAP compliance, lifestyle modification, somnolence status, and antihypertensive medication on the association between OSA and BP?
General	How much of the HTN-related CVD morbidity and mortality is attributed to sleep disturbances? What are the shared behavioral and physiologic pathways underlying the associations of sleep disturbances with BP? How does the presence of simultaneous sleep disturbances influence HTN risk and BP? How do structural level factors (e.g. racism, neighborhoods, socio-economic status) affect the association between sleep disturbances and HTN among different racial/ethnic groups?

^*BP: blood pressure; CPAP: continuous positive airway pressure; CVD: cardiovascular disease; HTN: hypertension; OSA: obstructive sleep apnea