Causes and Mechanisms of Nondipping Hypertension

Abstract

Growing evidence indicates that nondippers have worsened cardiovascular outcomes than dippers. Ambulatory blood pressure monitoring with a lack of nocturnal BP fall (nondipping) have also been shown to be more closely associated with target organ damage and worsened cardiovascular outcome than in patients with essential hypertension with dipping pattern. The underlying pathogenetic mechanisms potentially linking nondipping with cardiovascular disease are not fully understood. There are multiple possible underlying pathophysiologic mechanisms in the impaired BP decline during the night. Extrinsic and intrinsic factors including abnormal neurohormonal regulation, lack of physical activity, nutritional factors such as increased dietary sodium intake, and smoking of tobacco have been implicated for blunted circadian rhythm of BP. Certain diseases such as diabetes and chronic renal diseases also affect the circadian BP rhythm. Currently, the clinical importance of nondipping is known well; however, the relationship between certain disease states and nondipping has not been fully explained yet. This paper will attempt to address to clarify the underlying basis for nondipping and the specific associations with various disease states.

Behavioural and psychosocial correlates of nondipping blood pressure pattern among middle-aged men and women at work

“…8 Advanced age has been identified as an associative factor of nondipping in several studies, although not all research supports this finding. 8,9,14,24 The association with age was not confirmed in our study, which could be due to the relatively small age span in our sample. Nondipping was negatively associated with educational level and occupation, which is in line with findings from other studies suggesting higher risk of nondipping in people with lower socio-economic status.…”

“…Tobacco smoking and physical activity have been suggested as lifestyle factors associated with nondipping BP pattern, 9 although negative findings regarding the relation with smoking have also been reported. 14 Research on alcohol consumption in relation to nondipping, however, is almost nonexistent.…”

“…[5][6][7] On the other hand, the underlying pathophysiologic mechanisms and associative factors of this phenomenon are not fully understood. 8,9 In this study, the association between nondipping BP pattern, behavioural and psychosocial factors was assessed in a Correlates of nondipping E Clays et al sample of 167 middle-aged men and women at work free from overt coronary heart disease.…”

“…An impaired autonomic nervous system activity has been suggested as one of the possible pathophysiologic mechanisms of impaired nocturnal BP decline. 8,9 A review on this topic has shown that there is also evidence to suggest an association with some demographic, lifestyle and physiological factors such as age, gender, ethnicity, lower socio-economic status, lack of physical activity, nutritional factors, tobacco smoking and sleep quality. 8 In addition, the review revealed that psychosocial factors such as anger, hostility, depression and stress have been reported among hypertensive individuals with a nondipping BP profile, although this needs confirmation in larger study groups using standardized methods.…”

Non-dipping phenomenon in patients with essential hypertension with renal cysts: Dr. B. Afsar responds

“…Second, not only aforementioned factors may be related with non-dipping but also many other factors and disease states can be related with non-dipping pattern [2]. For example, patients may have other causes of hypertension such as renovascular hypertension and we did not perform renal Doppler studies or renal vein sampling.…”