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Dipping And Non Dipping Health And Social Care Essay


Hypertension is associated with increased cardiovascular morbidity and mortality. The blood pressure (BP) has diurnal variations. A reduction in the night and an increment in the morning indicate the circadian cadence of BP. The circadian rhythm of blood BP is linked to a high time during the awake period and a low time over the sleep session. "Non-dipper" pattern means a diurnal variation of BP in which the nocturnal reduction of BP is attenuated or absent oneself. While there are many pathophysiologic contraption underlying abnormalities in the 24-hour BP profile, including abnormalities in activation of the renin-angiotensin aldosterone system. The clinical importance of changing of the diurnal variation of BP has been upwards proved by the fact that the non-dipper pattern is associated with progression of end-organ damage.

Keywords: Non-dipper patern, hypertension, cardiovasculer events, ambulatory blood pressure monitoring, blood pressure, diurnal variation.


BP is one of the very substantial physiological characters. It is sensitive to diurnal variations, activity patterns, diet, body weight and fat, socioeconomic circumstances, other physical and cultural circumstances apart from having a powerful genetic as well as physiological constituent (Banik, 2007). Neuroendocrine contraptions are considerable agent of the ordinary 24-hour BP pattern. Integration of the essential impellent factors of this transient instability is interceded by circadian rhythms of monoaminergic systems. Humoral secretions are typically intermittent, coupled either to sleep and/or the circadian endogenous central pacemaker clock, but demonstrating also weekly, monthly, seasonal. (Fabbian et al., 2012). BP changes pending the 24-hour period, the so-named circadian instability, and BP variation among measurements, actual instability, have received increasing attention. Although the importance of intrinsic instability has been invited when BP is gauged intermittently each 15 or 20 minutes, circadian instability has happen a progressively used parameter even if reproducibility has carried some constraints (Redon and Lurbe, 2008). BP has an everyday variation characterized by prominent reductions pending sleep, a quick ascend upon awakening, and increased variability during the awake time in ambulatory normal subjects and hypertensive patient (Millar-Craig et al., 1978). 24 hour ambulatory blood pressure monitoring (ABPM) can easily determine the circadian BP pattern: generally, systolic and diastolic BP display a nocturnal descent. Nocturnal BP values do not however always drop in essential hypertension: the subjects who demonstrate a nocturnal BP descent of at minimal 10% are named dippers; in other subjects, named non-dippers, BP conduct is characterized by a lack of or very restricted nocturnal BP fall. Several investigations have studied the association between the deficiency of or lowering of nocturnal non-dipper pattern and cardiovascular risk, displaying not only an enhance of organ damage, but a bigger prevalence of cardiovascular events also and raised cardiovascular mortality in non-dippers issues, both hypertensives and normotensives (Cicconetti et al., 2007). ABPM provides more information about 24-hour blood pressure profile than single office recording (White, 2008). Appraisal of the time course of BP over 24 hours can only be achieved using ABPM. ABPM can ensure second types of information that is of potential value in the clinical area. The first is an estimate of the diurnal rhythm of BP, and the second is BP is variability. There is growing evidence that ambulatory blood pressure and specially BP during evening time predict better cardiovascular happening than in office BP. (de la Sierra et al., 2009). During sleep, the systolic BP normally decreases >10% of daytime level. Systolic BP dipping lower than 10 % is named the nondipping pattern and has been connected to a raise in cardiovascular risk and subclinical organ damage in the heart, brain, and kidneys (Vasunta et al., 2012).

Dipping and non-dipping

Biological rhythms are a crucial part of homoeostasis, 'everything is cadenced unless attested if notMost rhythms are controlled by an interior biological clock located in the suprachiasmatic nucleus and might be synchronized by external factors like light and dark cycles (Kitamura et al., 2002). ABPM divulges the important circadian alteration in BP, which in most persons presents a morning enhance, short post prandial drop, also more extensive reducing during nocturnal lounging period. Nevertheless, under certain pathophysiological circumstances, the nocturnal BP decrease can be reduced or even reversed (Hermida, 2007). The normal pattern of the daily rhythm of BP is a diminish of about 10 to 20% during the night, which coincides with hours of sleep, and is mostly called to as dipping. This pattern is not universal, however, and in about 25% of hypertensives a non-dipping pattern is seen in which the normal nocturnal decrease of pressure is absent (O'brien et al., 1988). A further assortment, some writers have used is to recognize people who show an immoderate tumble of BP (whose nocturnal pressure falls more than 20%) or a substantial increase.. ABPM is connected with further nearly with target organ hurm and cardiovascular happenings than clinical cuff measurements. This is clinically pertinent because the non-dipper and riser circadian BP patterns establish a risk factor for cerebrovascular disease, left ventricular hypertrophy, vascular dementia microalbuminuria, congestive heart failure. (Hermida et al., 2011).

Causes and clinical outcomes of non-dipper status

The "dipper-non dipper" grading was presented in 1988 when a retrospective study recommended so that non dipping hypertensive patients had a greater risk of stroke than the numerous number of patients with a dipping pattern (O'brien et al., 1988). It is commonly admitted that a lessened nocturnal BP deduct is associated with a poor prognosis (Pickering et al., 2006). In many patients, BP rises above daylight pressures rather than falling down during the night. These patients possess the poorly cardiovascular prognosis. (Kario and Shimada, 2004). A wide range of meanings is used to allocate the hypertensives with a rusted circadian pattern of blood pressure, labeled as "non dippers", from those offering with a typical night blood pressure drop, designated as "dippers". Last of all the prevalence popularity of non dipping event is quite unclear: from 6 to 40% of the hypertensive subjects, and the mechanisms of night blood pressure drop be left unclear, but the interest of autonomic nervous system turns out to be partially indicated (Ragot and Herpin, 1999). Changeability of blood pressure is more and more being identified as having a predictive value in clinical outcomes freely of the 24-hour average measure, as in the review article by Pickering and his colleagues (Pickering et al., 2006). The dipping patterns have been aforethought as a measure of blood pressure variability, paraphrased in line with, increased dietary sodium intake, abnormal neurohormonal regulation, lack of physical activity, smoking of tobacco. There are several likely pathophysiologic mechanisms underlying abnormality of the BP reduction during bedtime. Some diseases such as chronic renal diseases, diabetes, causes of secondary hypertension, thyroid and parathyroid diseases possibly affect the circadian BP rhythm (Covic and Goldsmith, 1999; Peixoto and White, 2002). The non-dipper patern is influenced by some factors such as horizontal posture and going to sleep, and body position. The quality of sleep mayhap affect dipping (Lusardi et al., 1996). One study discovered that non-dippers had a poorly sleep profile than dippers (Pedulla et al, 1995). Another factor affecting the state of non-dipper is volume and distribution of electrolytes in the body. The probable causes of unnatural circadian rhythm and non-dipper patern detailed in the Table 1, and currently, the relationship between certain disease states and non-dipper pattern has not been completely clarified yet (Birkenhäger and van den Meiracker, 2007; Kanbay et al., 2008).

Table 1. Causes of abnormal circadian rhythm and non-dipper patern in hypertension

Aging Diabetic neuropathy

Smoking Acromegaly

Ethnicity Benign prostate hyperplasia

Chronic renal failure Uraemic neuropathy

Hyperthyroidism Diabetes mellitus

Hyperparathyroidism Pheochromocytoma

Obstructive sleep apnoea syndrome Renal transplantation

Metabolic syndrome Hyperuricemia

The non-dipper status is correlated to a higher risk of cardiovascular events than dipping. Any prospective studies have discovered that non-dipping is linked with a higher risk than dipping. The first of these, Ohasama work has displayed that non-dipper status were independent predictors of the risk of cardiovascular mortality (Ohkubo et al., 2002).

The another one was the Italian PIUMA study, non-dippers were twofold the risk of cardiovasculer events more than dippers (Verdecchia et al., 1996). The non-dipping pattern mayhap a risk factor for progression of renal damage. This situation is supported by results of a study by Timio and his colleagues. According to the results of this study, non-dippers were a faster rate of reduce in creatinine clearance compared with dippers and non-dippers were greater enhances in proteinuria compared with dippers (Pickering, TG., 2007). Another research has made Liu and co-workers, a prognostic study of eighty Japanese patients with end-stage renal diseas who were followed for seven years, which found that the non-dipper pattern is closely associated to a high incidence of cardiovascular events, a poor long-term survival and profound autonomic dysfunction, and ABPM is beneficial in predicting long-term cardiovascular prognosis in HD patients (Liu et al., 2003). A prospective study investigated 3344 subjects by conducted Hermida and collageus who were followed for 5.6 years, which found that a non-dipper BP pattern had higher cardiovascular risk, whether BP was within the normotensive range or above it (Hermida et al., 2010). The participation among non-dipping and target organ damage, nevertheless, remains a little contentious. In a study conducted by Cuspidi et al  were found that in cured essential hypertensives with or without BP control the extent of nocturnal BP reduce is not associated with an enhance in left ventricul mass or left ventricular hypertrophy prevalence; consequently, the non-dipping profile, diagnosed on the basis of a single ABPM, does not identify hypertensive patients with larger cardiac damage. In this regard, the new studies redound a new extent to the subject (Cuspidi et al., 2003).


Non-dippper pattern has been related to increased end-organ damage and cardiovascular risk. Knowledge of the potential factors associated with an altered non-dipper pattern is of importance because it can help identify persons at risk for nondipper pattern and potential target organ damage. Furthermore, knowledge of these factors associated with a nondipper BP profile will lay the foundation for interventions to treat alterations in nighttime BP patterns.

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