Objective: Set of new markers obtained from ABPM has been used to improve sensitivity and specificity in the evaluation of the diagnosis of hypertension and effectiveness of the treatment. Among these parameters is the use of blood pressure load, the percentage of values above a given constant reference limit or computed by reference to daytime and nighttime limits. Aim was to investigate the percentage of blood pressure load and it's benefit as a marker of hypertension control in patients with sleep apnoae-hypopnea syndrome. Design and method: Research included 100 patients who underwent polysomnograpic examination in UCC Kragujevac. According to apnea-hypopnea index (AHI) all patients were divided into 4 equal groups, 25 patients in each group (AHI < 5; 5-15; 15-30 and > 30). Data for history of hypertension and antihypertensive treatment were collected anamnestically, and office blood pressure was measured baseline. All patients underwent single 24-h ambulatory BP monitoring. We calculated 24-h, daytime and nighttime BP loads separately for systolic and diastolic BP. We used 20% of load for each parameter as threshold for higher load. All data were statistically analyzed in the SPSS for Windows. Results: Study population consisted of 69% of male and 31% of female patients with mean age of 55.05 +/- 11.16 years. Prior hypertension was present in 76% of patients (x2 = 27.04; p = 0.000) in total group, with 68% on antihypertensive therapy (x2 = 12.96; p = 0.000). Among patients with diagnosed sleep apnea-hypopnea 62% had hypertension (x2 = 7.31; p = 0.007). The mean office SBP and DBP were both higher than guideline recomendations (140.39 mmHg SBP, 85.24 mmHg DBP). Mean values of BP load components were in mmHg: dSBP-27.74 +/- 3.36; nSBP-31.06 +/- 3.76; 24h-SBP-27.22 +/- 3.30; dDBP-24.96 +/- 3.02; nDBP-24.98 +/- 3.03; 24h-DBP-22.63 +/- 2.74. One-way ANOVA have shown significance in all blood pressure load parameters in patients on antihypertensive therapy (daytime SBP, p = 0.006; nighttime SBP, p = 0.000; 24h-SBP, p = 0.001; daytime DBP, p = 0.034; nighttime DBP, p = 0.28; 24h-DBP, p = 0.019). Conclusions: Hypertension is highly prevalent in patients with sleep apnoea-hypopnea syndrome, with the majority of patients treated with antihypertensive therapy. Office SBP and DBP, as well as all blood pressure load components have shown that hypertension had a poor control in these patients. Copyright