Additive Effects of Obstructive Sleep Apnea and Hypertension on Early Markers of Carotid Atherosclerosis

Hypertension Unit, Pulmonary Division, Heart Institute (InCor), University of Saõ Paulo Medical School, Saõ Paulo, Brazil.
Hypertension (Impact Factor: 6.48). 11/2008; 53(1):64-9. DOI: 10.1161/HYPERTENSIONAHA.108.119420
Source: PubMed


Obstructive sleep apnea (OSA) has emerged as an independent risk factor for atherosclerosis. However, OSA is frequently associated with several risk factors for atherosclerosis, including hypertension (HTN). The impact of OSA and HTN alone compared with the association of both conditions on carotid atherosclerosis is not understood. We studied 94 middle-aged participants free of smoking and diabetes mellitus who were divided into 4 groups: controls (n=22), OSA (n=25), HTN (n=20), and OSA+HTN (n=27). All of the participants underwent polysomnography and carotid measurements of intima-media thickness, diameter, and distensibility with an echo-tracking device. Compared with controls, intima-media thickness and carotid diameter were similarly higher in OSA (713+/-117 and 7117+/-805 microm), and HTN groups (713+/-182 and 7191+/-818 microm), with a further significant increase in OSA+HTN patients (837+/-181 and 7927+/-821 microm, respectively; P<0.01). Carotid distensibility was significantly lower in HTN (P<0.05) and OSA+HTN subjects (P<0.001) compared with controls. In the OSA+HTN group, carotid distensibility was significantly lower than in the OSA group and controls (P<0.05 for each comparison). Multivariate analysis showed that intima-media thickness was positively related to systolic blood pressure and apnea-hypopnea index. Apnea-hypopnea index was the only factor related to carotid diameter. Age and systolic blood pressure were independently related to carotid distensibility. In conclusion, the association of OSA and HTN has additive effects on markers of carotid atherosclerosis. Because early markers of carotid atherosclerosis predict future cardiovascular events, including not only stroke but also myocardial infarction, these findings may help to explain the increased risk of cardiovascular disease in patients with OSA.

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    • "The prevalence rate of sleep disorders in patients with CKD ranges from 40% to 80%, which is higher than those in the general population [4]. The most frequent comorbidities include diabetes mellitus type 2 [1], periodic leg movements during sleep [4], obstructive sleep apnea (OSA) and nocturnal hypoxemia [5], dyslipidaemia, coronary disease, heart failure [6,7], systemic arterial hypertension [8,9], respiratory disorders [10,11], stress[12 ], depression [12-14], anxiety [15]. "
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    • "Also, studies in which the additive effects of OSA and another disease process, that is, HTN, metabolic syndrome (MetS) on CIMT, were evaluated; both sets of data were included separately into the meta-analysis. For example, Drager and colleagues [17] [18] measured CIMT on patients diagnosed with hypertension and without hypertension with and without OSA. Similarly, Monneret and colleagues [19] measured CIMT on patients diagnosed with metabolic syndrome, with and without OSA. "
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    International journal of vascular medicine 08/2013; 2013:839582. DOI:10.1155/2013/839582
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    • "As recently reported [23], several studies performed in middle-aged SDB patients have demonstrated an association between SDB and atherogenesis, IMT and diameter and number of atheromatous plaques increasing in SDB patients [24] [25] [26] [27]. However, when we considered the atherosclerotic risk, this was significantly greater in hypertensive patients [28] [29], in patients with metabolic syndrome [30] and in severe SDB cases [15] [31] suggesting the interplay of several factors in the association between atherosclerosis and SDB. "
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