Estrogen-related mood disorders: reproductive life cycle factors

Women are at higher risk throughout their reproductive lives than are men for major depression. Numerous molecular and clinical studies have implicated estrogen in modulating brain function including that related to mood. In an attempt to present a conceptual model, the literature of the past 30 years on mood and well-being throughout reproductive life is reviewed as it relates to activity of endogenous, bio-identical, and synthetic estrogen in women. Results indicate that sudden estrogen withdrawal, fluctuating estrogen, and sustained estrogen deficit are correlated with significant mood disturbance. Clinical recovery from depression postpartum, perimenopause, and postmenopause through restoration of stable/optimal levels of estrogen has been noted.

Determination of the burden of care in families of cardiac surgery patients

"Burden of care" is a term that describes the effects of the multifaceted stressors associated with providing care to an ill family member. Descriptions of burden of care in acute care populations, such as families of patients who have had coronary artery bypass grafting, are very limited. The three purposes of this study were to describe the burden of care in families of coronary artery bypass grafting surgery patients, to compare the burden of care in families grouped by length of stay, and to provide evidence for the validity of the Caregiving Burden Scale in acute care populations. A survey was done using a longitudinal design over the first six weeks following coronary artery bypass grafting surgery. The 124 spouses of coronary artery bypass grafting surgery patients who participated reported a moderate degree of burden in caring for post cardiac surgery family members. Providing emotional support, taking over household tasks, and monitoring patients' conditions created the greatest burden for the participants. Length of stay in hospital did not have an impact on burden of care. The analysis of the data supports the validity of the Care-giving Burden Scale when used in the cardiac surgery population. (Prog Cardiovasc).

Correlation of the heart rate-minute ventilation relationship with clinical data: relevance to rate-adaptive pacing

The heart rate (HR)-minute ventilation (VE) relationship has been shown to be nonlinear and can be expressed as two distinct straight lines. This study is to assess the correlation of the initial HR-VE slope to clinical parameters. Maximum treadmill exercise tests were performed in 100 healthy volunteers (age 19-77 years) using a ramp protocol in which work-rate increases linearly with exercise. Breath-by-breath VO2, VCO2, and VE were measured, and HR and BP were monitored throughout the exercise. The HR-VE curve demonstrated nonlinearity with a breakpoint determined by a change point analysis. This breakpoint was significantly higher than that of the anaerobic threshold. The VE at the HR-VE breakpoint was 56.4 +/- 19.4 and VE at the VE-VO2-VO2 breakpoints were 48.0 +/- 18.3 (P < 0.0001) and 40.1 +/- 16.5 (P < 0.0001), respectively. The HR at this HR-Ve breakpoint was 77.7 +/- 12.9% of the HR range. The first slope, S1 (1.76 +/- 0.64) was steeper than the second slope, S2 (0.66 +/- 0.39). Although there was a gender difference for S1, the best clinical predictor on a stepwise multiple regression analysis was body surface area (BSA) which explained 47% of the variance. It was concluded that nonlinearity of the HR-VE curve can be expressed as two straight lines. The breakpoint is beyond the anaerobic threshold and can be estimated to be approximately 75% of the maximal predicted HR. BSA is the only clinical parameter that significantly predicts the initial slope of the HR-VE curve. This can be of great importance in the programming of rate-adaptive pacemakers using a VE.

Definition of life quality from a patient versus health care professional perspective

Quality of life assessment is increasingly acknowledged as an important component in selecting optimal health interventions for persons with cardiovascular disease. We hypothesized that cardiac out-patients have the same perception of what comprises quality of life as do their health care providers. A list of items was compiled from all quality of life measures and quality of life research. Staff members, cardiac out-patients and family members were asked what they considered important to the patients' quality of life by rating the relative importance of each item on the list. The three groups differed in their ratings. Of the top ten items ranked by patients, only three items appeared on the staff top ten list, and five on the family member's list. The patients, in contrast with staff and family, chose aspects of QL that reflected the positive aspects of life. These differences were more marked in the physical, psychological, and activity domains than in the social domain. The study suggests that QL measures developed from the perspective of primary caregivers are probably invalid and therefore QL measures should be developed from a patients perspective.