[Prognostic value of dipping status in untreated adult hypertensives from the Algerian population].

OBJECTIVE

Ambulatory blood pressure monitoring (ABPM) is the gold standard method for diagnosing hypertension (HTN). It allows for the determination of different blood pressure (BP) profiles according to the dipping status (DS). The objective of our study is to evaluate the impact of blood pressure profiles, according to dipping status, on target organ damage in a population of untreated adult hypertensives in Algeria.

METHODS

We recruited 304 untreated adult patients with hypertension. All our patients underwent 24-hour ambulatory blood pressure monitoring (ABPM) and the following TOD assessment: urinary albumin/creatinine (ACR), ECG, echocardiography, fundoscopy, and carotid ultrasound. Our patients were divided into four groups according to their dipping status (dipper, non-dipper, extreme dipping, and reverse dipping). We carried out a descriptive study followed by an analytic study in search of predictors of TOD.

RESULTS

The mean age of patients was 46.4±12years, with 82% males. The frequencies according to dipping status were as follows: dipper (n=106; 35.9%), non-dipper (n=157; 51.6%), extreme dipper (n=20; 6.6%) and reverse dipper (n=21; 6.9%). In bivariate analysis, there was no difference in TOD between the different groups except for vascular damage: dipper (16.2%), non-dipper (21.9%), extreme dipper (0%) and reverse dipper (47.4%); P<0.01. In logistic regression, cardiac damage was correlated with age (OR=1.035, P=0.006), nocturnal systolic BP (SBP) (OR=1.048, P=0.002) and body mass index (OR=1.115, P<0.001). Renal damage was correlated with diurnal SBP (OR=1.028; P<0.016) and glycated haemoglobin (OR=1.438, P<0.016). Vascular damage was correlated with age (OR=1.112, P<0.001), diurnal SBP (OR=1.061, P<0.001) and glycaemia (OR=1.016, P=0.022). Ophthalmic damage was correlated with nocturnal SBP (OR=1.021; P=0.03) and sedentarity (OR=1.758; P=0.036).

CONCLUSION

The non-dipper pattern was prevalent in our population. There was not a correlation between dipping status and TOD, except for the reverse dipper profile, which presents a higher vascular risk. The nocturnal SBP was a predictive factor for cardiac and ophthalmic damage; however, the diurnal SBP was a predictive factor for renal and vascular damage. These results support the strengthened integration of ABPM screening in the hypertensive patients in Algeria.