Blunted cardiovascular responses to daytime activities as related to reduced nocturnal blood pressure decline

The Night Side of Blood Pressure: Nocturnal Blood Pressure Dipping and Emotional (dys)Regulation

Introduction: The dipping phenomenon is a physiological drop in blood pressure (around 10-20%) during sleep and represents an event related to the circadian blood pressure trend. This phenomenon, in some cases, is characterized by some alterations that can be expressed by an increase (extreme dipping), a decrease (non-dipping), or a reverse (i.e., higher blood pressure during sleep compared to awake state; reverse-dipping) physiological decline of blood pressure. Few studies focused on the association between the circadian variation of blood pressure and psychological variables, although this information could help understanding how psychological characteristics (e.g., emotional regulation or dysregulation) interact with individuals' physiological processes. Given the association between emotional dysregulation and essential hypertension, this study aimed to investigate the relationship between alexithymia and dipping status in a sample of healthy and hypertensive adults in the absence of other medical conditions. Methods: Two hundred and ten adults took part in the study and were classified, according to ambulatorial blood pressure measure (ABPM), into three groups: dippers (n = 70), non-dippers (n = 70), and extreme dippers (n = 70). The participants completed a socio-demographic and anamnestic interview and the Toronto Alexithymia Scale-20 (TAS-20). Results: The ANOVAs on the TAS-20 subscales showed that the groups differed in the difficulty identifying feelings and difficulty describing feelings. In both the subscales, dippers showed lower scores than non-dippers and extreme dippers. The ANOVA on the global score of TAS-20 confirmed that dippers were less alexithymic than both extreme dippers and non-dippers. Conclusions: This study confirms that some psychological factors, like alexithymia, could represent a characteristic of patients who fail to exhibit an adaptive dipping phenomenon. Moreover, an association between an excessive reduction of BP (extreme dipping) or a lack of the decrease of BP during sleep (non-dipping) and a worse emotional regulation, considering alexithymia construct, was highlighted for the first time, confirming the relevant role of the emotional process in the modulation of an essential psychophysiological process such as the circadian variation of BP.

The Night Effect of Anger: Relationship with Nocturnal Blood Pressure Dipping

INTRODUCTION

The circadian pattern of blood pressure is characterized by a physiological drop occurring after sleep onset. The alteration of this phenomenon (non-dipping, extreme dipping, or reverse dipping) is associated with an increased cardiovascular risk. Besides altered autonomic and endocrine circadian rhythms, psychological aspects seem to play a role in this modification. However, the few studies that have analyzed the influence of psychological dimensions on the dipping phenomenon have reported inconsistent results. This study aimed to examine the relationship between anger expression and blood pressure (BP) dipping.

METHODS

We obtained 24 h ambulatory BP measurements from 151 participants and used them to define three groups according to their dipping status: Dippers (N = 65), Non-Dippers (N = 42), and Extreme Dippers (N = 44). Sociodemographic and anamnestic information was collected, and the State-Trait Anger Expression Inventory was used to assess anger.

RESULTS

Analysis of variance evidenced significant higher scores for Trait Anger Temperament and Anger Expression in Extreme Dippers than in both Dippers and Non-Dippers. However, after controlling for confounding variables, there was no significant relationship with trait anger, and only the result concerning the suppression of anger was confirmed.

CONCLUSIONS

These findings suggest that the analysis of some psychological factors, such as anger, could be necessary to better understand differences in nocturnal BP alterations. Trait anger and suppression of anger may contribute to the description and classification of patients who exhibit a maladaptive dipping phenomenon. However, modifiable (i.e., cigarette consumption) and unmodifiable (i.e., age) risk factors appear to mediate this relationship. Although further studies are necessary to explore this association, these results highlight that some aspects of anger can represent risk factors or markers of maladaptive modulation of the dipping phenomenon.

Ambulatory blood pressure and physical activity in heart failure

This observational study used repeated measures over 24 hr to investigate ambulatory blood pressure (BP) and physical activity (PA) profiles in community-based individuals with heart failure (HF). The aims were to (a) compare BP dipping and PA between two groups of HF patients with different functional statuses, and (b) determine whether the strength of the association between ambulatory BP and PA varies by functional status in HF. Ambulatory BP was measured every 30 min with a SpaceLabs 90207; a Basic Motionlogger actigraph was used to measure PA minute-by-minute. Fifty-six participants (54% female, age 66.96 + or - 12.35 years) completed data collection. Functional status was based on New York Heart Association (NYHA) ratings. Twenty-seven patients had no limitation of PA (NYHA Class I HF), whereas 29 had some limitation of PA but no discomfort at rest (NYHA Class II or III HF). Patients with Class I HF had a significantly greater degree of BP dipping than those with Class II/III HF after controlling for left ventricular ejection fraction. In a mixed-model analysis, PA was significantly related to ambulatory systolic and diastolic BP and mean arterial pressure. The strength of the association between PA and BP was not significantly different for the two groups of patients. These findings demonstrate differences between Class I and Class II/II HF in BP dipping status and ambulatory BP but not PA. Longitudinal research is recommended to improve understanding of the influence of disease progression on changes in 24-hr PA and BP profiles of patients with HF.

Can psychological factors account for a lack of nocturnal blood pressure dipping?

BACKGROUND

In healthy individuals, blood pressure (BP) decreases, or "dips", during sleep. Ethnicity and high daytime blood pressure level are known markers of nondipping status. The literature on psychological markers of nondipping is scant but suggests that anger/hostility and chronic stress may be contributors to nondipping.

PURPOSE

We have investigated this phenomenon in drug-free hypertensives who participated in a clinical trial and supplied extensive demographic, psychological, and biological risk factor data after medication washout prior to any treatment.

METHOD

Sixty-two patients were available for analysis (n = 30 nondippers). While most studies focus only on systolic BP nondipping, we explicitly studied both systolic and diastolic BP dipping as outcomes given that both have prognostic value.

RESULTS

Hierarchical multiple regression revealed that predictor variables in total accounted for 38% of variance in systolic blood pressure dipping and 44% of variance in diastolic blood pressure dipping. A significant positive predictor was alcohol consumption (beta = 0.37, t = 2.8, p = 0.007) for systolic BP and beta = 0.43, t = 3.7, p = 0.001 for diastolic BP), and an anger diffusion preference was also a positive predictor (beta = 0.42, t = 2.7, p = 0.01) for systolic BP dipping. No measure of trait negative affect reached significance as a predictor for systolic or diastolic BP dipping.

CONCLUSION

These findings suggest that for a better understanding of the nondipping phenomenon, behavioral risk factors are important, and anger response styles may also be worthy of further study. Furthermore, anger coping preferences may be as important, or even more so, than levels of negative affect.