1. Daily Stress, Coping, and Nocturnal Blood Pressure Dipping
Sean R. O’Quinn & Kevin T. Larkin
Department of Psychology, West Virginia University
METHOD
RESULTS (Continued)
RESULTS (Continued)
ABSTRACT
Recruitment: Participants were recruited from the Medical Group Practice and Hypertension Clinics at the Physicians Office Center of West Virginia University located in Morgantown, West Virginia. Participants were also recruited from the community by bulletin board announcements, television and radio advertisements, presentations to community groups, and by recruiting participants of previously conducted studies
Sample size: Thirty-five participants (14 Male, 21 Female) completed the seven day Daily Stress Inventory and COPE Inventory. Participants with diagnosed cardiovascular disease, diabetes mellitus, alcoholism, chronic renal failure, nephrotic syndrome, or significant current psychiatric impairment were excluded from participating in the study.
Healthy adults typically experience a dip in blood pressure (BP) while sleeping. Those who do not exhibit a dip in sleeping blood pressures may be at increased risk for various cardiovascular and cerebrovascular pathologies. The purpose of this study was to investigate the relation between blood pressure dipping and daily stress. Additionally the possible moderating effects of coping on the BP dipping-stress relation were examined. Thirty-five participants wore ambulatory blood pressure monitors for 24 hours to assess BP dipping in terms of systolic (SBP), diastolic (DBP), and mean arterial pressure (MAP). To examine the relation between stress and dipping the seven-day Daily Stress Inventory was used. Coping was assessed using the COPE Inventory. Among demographic variables, gender (r = -.45, p < .05), minutes of exercise per week (r = .48, p < .05), and resting clinic BP (r = .54, p < .05), were related to BP dipping, and were used as covariates in subsequent regression analyses. A series of regression analyses were conducted to assess whether measures of daily stress (both frequency and perceived intensity) predicted BP dipping and whether this relation was moderated by emotion-focused or problem-focused coping strategies. While no significant main effects were found for any measures of coping or daily stress, significant moderation effects were found for problem-focused coping and daily stress in predicting BP dipping status. Specifically, the relation between both number of stressful events and perceived intensity and dipping status was moderated by problem focused coping (MAP dipping: p < .05; SBP dipping: p < .05). Among individuals with fewer stressful events or low perceived stress, problem-focused coping was associated with greater BP dipping. Problem-focused coping was not related to BP dipping among persons with high levels of stress. These results indicate that problem focused coping is associated with healthy BP dipping, but only among individuals with lesser daily stress in their lives.
Regression Analyses
MAP – Number of Stressful Events
Coping/Stress Main Effects
Coping X Stress
Moderation R2
R2 Change
Sig PF
.554
.037
.644
.09
.013* EF
.548
.032
.570
.022 NS
*p < .05
DBP - Number of Stressful Events
Measurement of Ambulatory Blood Pressure:
Ambulatory blood pressure measurements were collected over a single 24 hour period using the Accutracker DX Ambulatory blood pressure monitor set to a cycle of 3 measurements per hour during the day and 2 per hour at night.
Measurement of Daily Stress and Coping:
The DSI was completed by participants each day for the course of one week, the first day being the day in which the participant wore the ambulatory blood pressure monitor. The DSI Event and Impact/Event (I/E) Ratio Scores were used. The COPE was administered to the participants during the initial clinic visit when the ambulatory monitor was fitted. The COPE is comprised of two scales: Problem Focused (PF) and Emotion Focused (EF).
Coping/Stress Main Effects
Coping X Stress
Moderation R2
R2 Change
Sig PF
.472
.04
.559
.087
.026* EF
.491
.059
.519
.028 NS
*p < .05
DBP - Perceived Stressfulness (I/E Ratio)
Coping/Stress Main Effects
Coping X Stress
Moderation R2
R2 Change
Sig PF
.483
.052
.494
.011 NS EF
.495
.063
.000
MAP - Perceived Stressfulness (I/E Ratio)
Coping/Stress Main Effects
Coping X Stress
Moderation R2
R2 Change
Sig PF
.564
.047
.606
.043
.093 EF
.554
.037
.557
.003 NS
CONCLUSIONS
RESULTS
Among the two types of coping examined only problem focused coping (PF) had a relation to BP dipper status.
Emotion focused coping (EF) did not significantly moderate the Stress-BP dipping relation.
Those with high levels of PF coping exhibited the greatest nocturnal mean blood pressure declines but only during low frequency of stressful events.
Individuals with high PF coping experienced more SBP dipping but only under conditions of low perceived (I/E ratio) stress.
Individuals with high PF coping scores exhibited more DBP dipping but only during low frequency of stressful events.
Under high frequency of stress, no measures of coping were related to magnitude of nocturnal blood pressure dipping.
SBP - Number of Stressful Events
Participant Demographic Characteristics
Variables Mean (SD) % N
Male %
Female %
Smokers %
Age (15.5)
Exercise Per week min (176)
Weight lbs (46.04)
Height in (3.91)
Participant Mean BP Characteristics
Variables Mean (SD)
Clinic SBP mm/Hg (16.8)
Clinic DBP mm/Hg (11.6)
Clinic MAP mm/Hg (12.6)
SBP Dip mm/Hg (11.0)
DBP Dip mm/Hg (8.30)
MAP Dip mm/Hg (8.52)
Coping/Stress Main Effects
Coping X Stress
Moderation R2
R2 Change
Sig PF
.510
.031
.573
.063
.051 EF
.485
.006
.494
.009 NS
OBJECTIVE
To examine the relation between blood pressure dipping and daily stress. Additionally, the study examined the possible moderating effects of various coping methods on the stress-blood pressure dipping relation and various
demographic variables that may impact dipping.
SBP - Perceived Stressfulness (I/E Ratio)
Coping/Stress Main Effects
Coping X Stress
Moderation R2
R2 Change
Sig PF
.511
.032
.617
.106
.009* EF
.485
.005
.494
.009 NS
*p < .01