Therapeutics
In patients with obstructive sleep apnea and resistant hypertension, CPAP reduced 24-hour blood pressure
Martínez-García MA, Capote F, Campos-Rodríguez F, et al. Effect of CPAP on blood pressure in patients with obstructive sleep apnea and resistant hypertension: the HIPARCO randomized clinical trial. JAMA. 2013;310:2407-15.
Clinical impact ratings: F ★★★★★✩✩ C ★★★★★✩✩ p ★★★★★★✩ Question
Conclusion
In patients with obstructive sleep apnea (OSA) and resistant hypertension, what is the effect of continuous positive airway pressure (CPAP) on blood pressure (BP)?
In patients with obstructive sleep apnea and resistant hypertension, continuous positive airway pressure reduced mean 24-hour blood pressure.
Methods
*See Glossary.
Design: Randomized controlled trial (HIPARCO trial). Clinicaltrials.gov NCT00616265. Allocation: Concealed.* Blinding: Blinded* (outcome assessors, {data analysts, and safety committee}†). Follow-up period: 12 weeks. Setting: Hypertension clinical units in 24 teaching hospitals in Spain. Patients: 194 patients aged 18 to 75 years (mean age 56 y, 69% men) who had OSA (apnea–hypopnea index [AHI] ≥ 15) based on overnight polysomnography (attended respiratory polygraphy) and primary resistant hypertension (systolic blood pressure [SBP] ≥ 130 mm Hg, diastolic blood pressure [DBP] ≥ 80 mm Hg, or both despite use of ≥ 3 antihypertensive medications including a diuretic, if not contraindicated) based on 24-hour ambulatory BP monitoring. Exclusion criteria included hypertension due to primary aldosteronism, renal artery stenosis, or renal insufficiency; disabling hypersomnia; current use of CPAP; poor adherence to antihypertensive treatment; cardiovascular event in the previous month; or use of oral corticosteroids, nonsteroidal antiinflammatory drugs, sedatives, or alcohol (> 100 g/d). Intervention: Nightly fixed-pressure CPAP, titrated to optimal pressure with an automatic CPAP device in a sleep laboratory (n = 98), or no CPAP (n = 96). All patients maintained their antihypertensive medication regimens. Outcomes: Primary outcome was change in 24-hour ambulatory mean BP from baseline. Secondary outcomes included change in diurnal and nocturnal SBP and DBP. Patient follow-up: 90% (intention-to-treat analysis).
†Information provided by author.
Sources of funding: Philips-Respironics; Sociedad Española de Neumología; Instituto de Salud Carlos III; Sociedad Valenciana de Neumología. For correspondence: Dr. M.A. Martínez-García, Hospital Universitario y Politécnico La Fe, Valencia, Spain. E-mail mianmartinezgarcia@ gmail.com. ■
Commentary
OSA is a well-recognized risk factor for, and can be present in up to 70% of patients with, resistant hypertension (1). Nondipping BP (defined as < 10% reduction in nocturnal BP) has been shown to predict adverse cardiovascular events (2). A recent study in patients with well-controlled hypertension and untreated OSA showed that, in a subgroup of patients with severe OSA, each unit increase in OSA severity as measured by Oxygen Desaturation Index or AHI was associated with 4% to 10% higher odds of nondipping BP (3). Studies have examined the effect of treatment with CPAP on BP with variable results (1, 4). Martinez-Garcia and colleagues report results from a large randomized multicenter trial examining the effect of CPAP on BP in patients with resistant hypertension. The study showed that CPAP, typically used for ≥ 4 hours per night, resulted in a meaningful reduction in 24-hour mean BP in patients with severe OSA (mean AHI 40.4). Of note, 74% of study patients had a nondipper or riser pattern at baseline, and this pattern was more likely to be corrected in the CPAP group than in the control group at the end of the 12-week follow-up. These results, along with the association between OSA severity and nondipping BP in untreated OSA (3), suggest that the effect of untreated OSA in patients with “resistant hypertension” is often a nondipping BP pattern. Main results CPAP reduced mean 24-hour BP, SBP, and DBP, and nocturnal Aside from the effect on nocturnal hemodynamic indices, the SBP and DBP more than no CPAP (Table). study confirms the degree of improvement in BP based on the number of hours of CPAP used. The benefits of CPAP Continuous positive airway pressure (CPAP) vs no CPAP in patients with require adherence to the therapy, which can be challenging obstructive sleep apnea and resistant hypertension‡ for many patients (5). Further research is also needed to evaluate effects of CPAP on long-term clinical outcomes. Outcomes Mean BP (mm Hg) Adjusted mean difference (95% CI) in change from baseline to 12 wk§
Roop Kaw, MD Cleveland Clinic Cleveland, Ohio, USA
CPAP at CPAP at No CPAP at No CPAP at baseline 12 wk baseline 12 wk 24-h mean BP
103.9
99.8
102.9
102.1
3.9 (1.3 to 6.6)
24-h mean SBP
144.9
140.2
143.5
142.3
4.2 (0.4 to 8.0)
24-h mean DBP
83.4
79.5
82.6
82.1
3.8 (1.4 to 6.1)
Diurnal SBP
147.2
144.0
145.1
142.5
1.1 (−2.9 to 5.2)
Diurnal DBP
85.7
82.7
84.6
83.2
2.3 (−0.1 to 4.8)
Nocturnal SBP
141.2
134.6
140.4
137.8
5.8 (1.1 to 10.5)
Nocturnal DBP
78.5
75.4
78.6
77.5
3.3 (0.5 to 6.1)
References 1. Logan AG, Tkacova R, Perlikowski SM, et al. Eur Respir J. 2003; 21:241-7. 2. Fagard RH, Celis H, Thijs L, et al. Hypertension. 2008;51:55-61. 3. Seif F, Patel SR, Walia HK, et al. J Hypertens. 2014;32:267-75. 4. Lozano L, Tovar JL, Sampol G, et al. J Hypertens. 2010;28:2161-8. 5. Weaver TE, Grunstein RR. Proc Am Thorac Soc. 2008;5:173-8.
‡BP = blood pressure; DBP = diastolic BP; SBP = systolic BP; other abbreviations defined in Glossary. Data imputed for 20 patients. §Adjusted for baseline BP, apnea–hypopnea index, Epworth Sleepiness Scale, dipper or riser status, and previous cardiovascular events.
JC10
© 2014 American College of Physicians
15 April 2014 | ACP Journal Club | Volume 160 • Number 8
Downloaded From: https://annals.org/pdfaccess.ashx?url=/data/journals/aim/929992/ by a Tufts University User on 07/27/2017
In patients with obstructive sleep apnea and resistant hypertension, CPAP reduced 24-hour blood pressure
Martínez-García MA, Capote F, Campos-Rodríguez F, et al. Effect of CPAP on blood pressure in patients with obstructive sleep apnea and resistant hypertension: the HIPARCO randomized clinical trial. JAMA. 2013;310:2407-15.
Clinical impact ratings: F ★★★★★✩✩ C ★★★★★✩✩ p ★★★★★★✩ Question
Conclusion
In patients with obstructive sleep apnea (OSA) and resistant hypertension, what is the effect of continuous positive airway pressure (CPAP) on blood pressure (BP)?
In patients with obstructive sleep apnea and resistant hypertension, continuous positive airway pressure reduced mean 24-hour blood pressure.
Methods
*See Glossary.
Design: Randomized controlled trial (HIPARCO trial). Clinicaltrials.gov NCT00616265. Allocation: Concealed.* Blinding: Blinded* (outcome assessors, {data analysts, and safety committee}†). Follow-up period: 12 weeks. Setting: Hypertension clinical units in 24 teaching hospitals in Spain. Patients: 194 patients aged 18 to 75 years (mean age 56 y, 69% men) who had OSA (apnea–hypopnea index [AHI] ≥ 15) based on overnight polysomnography (attended respiratory polygraphy) and primary resistant hypertension (systolic blood pressure [SBP] ≥ 130 mm Hg, diastolic blood pressure [DBP] ≥ 80 mm Hg, or both despite use of ≥ 3 antihypertensive medications including a diuretic, if not contraindicated) based on 24-hour ambulatory BP monitoring. Exclusion criteria included hypertension due to primary aldosteronism, renal artery stenosis, or renal insufficiency; disabling hypersomnia; current use of CPAP; poor adherence to antihypertensive treatment; cardiovascular event in the previous month; or use of oral corticosteroids, nonsteroidal antiinflammatory drugs, sedatives, or alcohol (> 100 g/d). Intervention: Nightly fixed-pressure CPAP, titrated to optimal pressure with an automatic CPAP device in a sleep laboratory (n = 98), or no CPAP (n = 96). All patients maintained their antihypertensive medication regimens. Outcomes: Primary outcome was change in 24-hour ambulatory mean BP from baseline. Secondary outcomes included change in diurnal and nocturnal SBP and DBP. Patient follow-up: 90% (intention-to-treat analysis).
†Information provided by author.
Sources of funding: Philips-Respironics; Sociedad Española de Neumología; Instituto de Salud Carlos III; Sociedad Valenciana de Neumología. For correspondence: Dr. M.A. Martínez-García, Hospital Universitario y Politécnico La Fe, Valencia, Spain. E-mail mianmartinezgarcia@ gmail.com. ■
Commentary
OSA is a well-recognized risk factor for, and can be present in up to 70% of patients with, resistant hypertension (1). Nondipping BP (defined as < 10% reduction in nocturnal BP) has been shown to predict adverse cardiovascular events (2). A recent study in patients with well-controlled hypertension and untreated OSA showed that, in a subgroup of patients with severe OSA, each unit increase in OSA severity as measured by Oxygen Desaturation Index or AHI was associated with 4% to 10% higher odds of nondipping BP (3). Studies have examined the effect of treatment with CPAP on BP with variable results (1, 4). Martinez-Garcia and colleagues report results from a large randomized multicenter trial examining the effect of CPAP on BP in patients with resistant hypertension. The study showed that CPAP, typically used for ≥ 4 hours per night, resulted in a meaningful reduction in 24-hour mean BP in patients with severe OSA (mean AHI 40.4). Of note, 74% of study patients had a nondipper or riser pattern at baseline, and this pattern was more likely to be corrected in the CPAP group than in the control group at the end of the 12-week follow-up. These results, along with the association between OSA severity and nondipping BP in untreated OSA (3), suggest that the effect of untreated OSA in patients with “resistant hypertension” is often a nondipping BP pattern. Main results CPAP reduced mean 24-hour BP, SBP, and DBP, and nocturnal Aside from the effect on nocturnal hemodynamic indices, the SBP and DBP more than no CPAP (Table). study confirms the degree of improvement in BP based on the number of hours of CPAP used. The benefits of CPAP Continuous positive airway pressure (CPAP) vs no CPAP in patients with require adherence to the therapy, which can be challenging obstructive sleep apnea and resistant hypertension‡ for many patients (5). Further research is also needed to evaluate effects of CPAP on long-term clinical outcomes. Outcomes Mean BP (mm Hg) Adjusted mean difference (95% CI) in change from baseline to 12 wk§
Roop Kaw, MD Cleveland Clinic Cleveland, Ohio, USA
CPAP at CPAP at No CPAP at No CPAP at baseline 12 wk baseline 12 wk 24-h mean BP
103.9
99.8
102.9
102.1
3.9 (1.3 to 6.6)
24-h mean SBP
144.9
140.2
143.5
142.3
4.2 (0.4 to 8.0)
24-h mean DBP
83.4
79.5
82.6
82.1
3.8 (1.4 to 6.1)
Diurnal SBP
147.2
144.0
145.1
142.5
1.1 (−2.9 to 5.2)
Diurnal DBP
85.7
82.7
84.6
83.2
2.3 (−0.1 to 4.8)
Nocturnal SBP
141.2
134.6
140.4
137.8
5.8 (1.1 to 10.5)
Nocturnal DBP
78.5
75.4
78.6
77.5
3.3 (0.5 to 6.1)
References 1. Logan AG, Tkacova R, Perlikowski SM, et al. Eur Respir J. 2003; 21:241-7. 2. Fagard RH, Celis H, Thijs L, et al. Hypertension. 2008;51:55-61. 3. Seif F, Patel SR, Walia HK, et al. J Hypertens. 2014;32:267-75. 4. Lozano L, Tovar JL, Sampol G, et al. J Hypertens. 2010;28:2161-8. 5. Weaver TE, Grunstein RR. Proc Am Thorac Soc. 2008;5:173-8.
‡BP = blood pressure; DBP = diastolic BP; SBP = systolic BP; other abbreviations defined in Glossary. Data imputed for 20 patients. §Adjusted for baseline BP, apnea–hypopnea index, Epworth Sleepiness Scale, dipper or riser status, and previous cardiovascular events.
JC10
© 2014 American College of Physicians
15 April 2014 | ACP Journal Club | Volume 160 • Number 8
Downloaded From: https://annals.org/pdfaccess.ashx?url=/data/journals/aim/929992/ by a Tufts University User on 07/27/2017
