title: Clinic Versus Daytime Ambulatory Blood Pressure Difference in Hypertensive Patients: The Impact of Age and Clinic Blood Pressure.
abstract: Clinic blood pressure (BP) is usually higher than daytime ambulatory BP in hypertensive patients, but some recent studies have challenged this view, suggesting that this relationship is strongly influenced by age. We used the Spanish ambulatory BP monitoring cohort to examine differences between clinic and daytime BP by age among 104 639 adult hypertensive patients (office systolic/diastolic BP ≥140/90 mm Hg or treated) in usual primary-care practice, across the wide age spectrum. To assess the impact of age, cardiovascular variables, and clinic BP on the clinic-daytime BP differences, we built multivariable regression models of the average BP differences, white-coat hypertension (high clinic BP and normal daytime BP), and masked hypertension (normal clinic BP and high daytime BP). In most patients, mean clinic BP values were higher than daytime BP at all ages. Some 36.7% of patients had white-coat hypertension (amounting to 50% at clinic systolic BP of 140-159 mm Hg) and 3.9% had masked hypertension (amounting to 18% at clinic systolic BP of 130-139 mm Hg). Age explained 0.1% to 1.7% of the variance of quantitative or categorical BP differences (P<0.001). Cardiovascular variables explained an additional 1.6% to 3.4% of the variance (P<0.001). Finally, clinic BP generally explained ≥20% more of the variance (P<0.01). In this large study in usual clinical practice, clinic BP misclassified hypertension status in >40% of patients. This misclassification was not importantly influenced by age but was more evident in patients with borderline/grade 1 hypertension. These findings reinforce the importance of ambulatory BP monitoring for defining BP status in routine clinical practice.
authors.affiliation: From the Department of Preventive Medicine and Public Health, Universidad Autónoma de Madrid/IdiPAZ and CIBER in Epidemiology and Public Health (CIBERESP), Spain (J.R.B., L.M.R., J.J.d.l.C.); Instituto de Investigación Hospital Doce de Octubre, Madrid, Spain (L.M.R.); Department of Internal Medicine, Hospital Mutua Terrassa, University of Barcelona, Spain (A.d.l.S.); La Mina Primary Care Center, Department of Medicine, University of Barcelona, Spain (E.V.); Nephrology Service, Department of Medicine, Hospital Universitario Central de Asturias, RedinRed, Oviedo, Spain (M.G.); Hypertension Unit, Department of Nephrology, Hospital Doce de Octubre, Madrid, Spain (J.S.); Hypertension Unit, Department of Nephrology, Hospital Universitari del Mar and IMIM (Institut Hospital del Mar d'Investigacions Mèdiques), Barcelona, Spain (A.O.); Hypertension Unit, Department of Medicine, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria del HCSC, Madrid, Spain (N.M.); Cardiometabolic and Hypertension Unit, Department of Medicine, Hospital Universitario La Paz, Universidad Autónoma de Madrid/IdiPAZ, Madrid, Spain (J.G.-P.); and University College London (UCL) Institute of Cardiovascular Science and NIHR UCL Hospitals Biomedical Research Centre, United Kingdom (B.W.). joseramon.banegas@uam.es.
authors.forename: José R
authors.initials: JR
authors.lastname: Banegas
authors.affiliation: From the Department of Preventive Medicine and Public Health, Universidad Autónoma de Madrid/IdiPAZ and CIBER in Epidemiology and Public Health (CIBERESP), Spain (J.R.B., L.M.R., J.J.d.l.C.); Instituto de Investigación Hospital Doce de Octubre, Madrid, Spain (L.M.R.); Department of Internal Medicine, Hospital Mutua Terrassa, University of Barcelona, Spain (A.d.l.S.); La Mina Primary Care Center, Department of Medicine, University of Barcelona, Spain (E.V.); Nephrology Service, Department of Medicine, Hospital Universitario Central de Asturias, RedinRed, Oviedo, Spain (M.G.); Hypertension Unit, Department of Nephrology, Hospital Doce de Octubre, Madrid, Spain (J.S.); Hypertension Unit, Department of Nephrology, Hospital Universitari del Mar and IMIM (Institut Hospital del Mar d'Investigacions Mèdiques), Barcelona, Spain (A.O.); Hypertension Unit, Department of Medicine, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria del HCSC, Madrid, Spain (N.M.); Cardiometabolic and Hypertension Unit, Department of Medicine, Hospital Universitario La Paz, Universidad Autónoma de Madrid/IdiPAZ, Madrid, Spain (J.G.-P.); and University College London (UCL) Institute of Cardiovascular Science and NIHR UCL Hospitals Biomedical Research Centre, United Kingdom (B.W.).
authors.forename: Luis M
authors.initials: LM
authors.lastname: Ruilope
authors.affiliation: From the Department of Preventive Medicine and Public Health, Universidad Autónoma de Madrid/IdiPAZ and CIBER in Epidemiology and Public Health (CIBERESP), Spain (J.R.B., L.M.R., J.J.d.l.C.); Instituto de Investigación Hospital Doce de Octubre, Madrid, Spain (L.M.R.); Department of Internal Medicine, Hospital Mutua Terrassa, University of Barcelona, Spain (A.d.l.S.); La Mina Primary Care Center, Department of Medicine, University of Barcelona, Spain (E.V.); Nephrology Service, Department of Medicine, Hospital Universitario Central de Asturias, RedinRed, Oviedo, Spain (M.G.); Hypertension Unit, Department of Nephrology, Hospital Doce de Octubre, Madrid, Spain (J.S.); Hypertension Unit, Department of Nephrology, Hospital Universitari del Mar and IMIM (Institut Hospital del Mar d'Investigacions Mèdiques), Barcelona, Spain (A.O.); Hypertension Unit, Department of Medicine, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria del HCSC, Madrid, Spain (N.M.); Cardiometabolic and Hypertension Unit, Department of Medicine, Hospital Universitario La Paz, Universidad Autónoma de Madrid/IdiPAZ, Madrid, Spain (J.G.-P.); and University College London (UCL) Institute of Cardiovascular Science and NIHR UCL Hospitals Biomedical Research Centre, United Kingdom (B.W.).
authors.forename: Alejandro
authors.initials: A
authors.lastname: de la Sierra
authors.affiliation: From the Department of Preventive Medicine and Public Health, Universidad Autónoma de Madrid/IdiPAZ and CIBER in Epidemiology and Public Health (CIBERESP), Spain (J.R.B., L.M.R., J.J.d.l.C.); Instituto de Investigación Hospital Doce de Octubre, Madrid, Spain (L.M.R.); Department of Internal Medicine, Hospital Mutua Terrassa, University of Barcelona, Spain (A.d.l.S.); La Mina Primary Care Center, Department of Medicine, University of Barcelona, Spain (E.V.); Nephrology Service, Department of Medicine, Hospital Universitario Central de Asturias, RedinRed, Oviedo, Spain (M.G.); Hypertension Unit, Department of Nephrology, Hospital Doce de Octubre, Madrid, Spain (J.S.); Hypertension Unit, Department of Nephrology, Hospital Universitari del Mar and IMIM (Institut Hospital del Mar d'Investigacions Mèdiques), Barcelona, Spain (A.O.); Hypertension Unit, Department of Medicine, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria del HCSC, Madrid, Spain (N.M.); Cardiometabolic and Hypertension Unit, Department of Medicine, Hospital Universitario La Paz, Universidad Autónoma de Madrid/IdiPAZ, Madrid, Spain (J.G.-P.); and University College London (UCL) Institute of Cardiovascular Science and NIHR UCL Hospitals Biomedical Research Centre, United Kingdom (B.W.).
authors.forename: Ernest
authors.initials: E
authors.lastname: Vinyoles
authors.affiliation: From the Department of Preventive Medicine and Public Health, Universidad Autónoma de Madrid/IdiPAZ and CIBER in Epidemiology and Public Health (CIBERESP), Spain (J.R.B., L.M.R., J.J.d.l.C.); Instituto de Investigación Hospital Doce de Octubre, Madrid, Spain (L.M.R.); Department of Internal Medicine, Hospital Mutua Terrassa, University of Barcelona, Spain (A.d.l.S.); La Mina Primary Care Center, Department of Medicine, University of Barcelona, Spain (E.V.); Nephrology Service, Department of Medicine, Hospital Universitario Central de Asturias, RedinRed, Oviedo, Spain (M.G.); Hypertension Unit, Department of Nephrology, Hospital Doce de Octubre, Madrid, Spain (J.S.); Hypertension Unit, Department of Nephrology, Hospital Universitari del Mar and IMIM (Institut Hospital del Mar d'Investigacions Mèdiques), Barcelona, Spain (A.O.); Hypertension Unit, Department of Medicine, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria del HCSC, Madrid, Spain (N.M.); Cardiometabolic and Hypertension Unit, Department of Medicine, Hospital Universitario La Paz, Universidad Autónoma de Madrid/IdiPAZ, Madrid, Spain (J.G.-P.); and University College London (UCL) Institute of Cardiovascular Science and NIHR UCL Hospitals Biomedical Research Centre, United Kingdom (B.W.).
authors.forename: Manuel
authors.initials: M
authors.lastname: Gorostidi
authors.affiliation: From the Department of Preventive Medicine and Public Health, Universidad Autónoma de Madrid/IdiPAZ and CIBER in Epidemiology and Public Health (CIBERESP), Spain (J.R.B., L.M.R., J.J.d.l.C.); Instituto de Investigación Hospital Doce de Octubre, Madrid, Spain (L.M.R.); Department of Internal Medicine, Hospital Mutua Terrassa, University of Barcelona, Spain (A.d.l.S.); La Mina Primary Care Center, Department of Medicine, University of Barcelona, Spain (E.V.); Nephrology Service, Department of Medicine, Hospital Universitario Central de Asturias, RedinRed, Oviedo, Spain (M.G.); Hypertension Unit, Department of Nephrology, Hospital Doce de Octubre, Madrid, Spain (J.S.); Hypertension Unit, Department of Nephrology, Hospital Universitari del Mar and IMIM (Institut Hospital del Mar d'Investigacions Mèdiques), Barcelona, Spain (A.O.); Hypertension Unit, Department of Medicine, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria del HCSC, Madrid, Spain (N.M.); Cardiometabolic and Hypertension Unit, Department of Medicine, Hospital Universitario La Paz, Universidad Autónoma de Madrid/IdiPAZ, Madrid, Spain (J.G.-P.); and University College London (UCL) Institute of Cardiovascular Science and NIHR UCL Hospitals Biomedical Research Centre, United Kingdom (B.W.).
authors.forename: Juan J
authors.initials: JJ
authors.lastname: de la Cruz
authors.affiliation: From the Department of Preventive Medicine and Public Health, Universidad Autónoma de Madrid/IdiPAZ and CIBER in Epidemiology and Public Health (CIBERESP), Spain (J.R.B., L.M.R., J.J.d.l.C.); Instituto de Investigación Hospital Doce de Octubre, Madrid, Spain (L.M.R.); Department of Internal Medicine, Hospital Mutua Terrassa, University of Barcelona, Spain (A.d.l.S.); La Mina Primary Care Center, Department of Medicine, University of Barcelona, Spain (E.V.); Nephrology Service, Department of Medicine, Hospital Universitario Central de Asturias, RedinRed, Oviedo, Spain (M.G.); Hypertension Unit, Department of Nephrology, Hospital Doce de Octubre, Madrid, Spain (J.S.); Hypertension Unit, Department of Nephrology, Hospital Universitari del Mar and IMIM (Institut Hospital del Mar d'Investigacions Mèdiques), Barcelona, Spain (A.O.); Hypertension Unit, Department of Medicine, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria del HCSC, Madrid, Spain (N.M.); Cardiometabolic and Hypertension Unit, Department of Medicine, Hospital Universitario La Paz, Universidad Autónoma de Madrid/IdiPAZ, Madrid, Spain (J.G.-P.); and University College London (UCL) Institute of Cardiovascular Science and NIHR UCL Hospitals Biomedical Research Centre, United Kingdom (B.W.).
authors.forename: Julián
authors.initials: J
authors.lastname: Segura
authors.affiliation: From the Department of Preventive Medicine and Public Health, Universidad Autónoma de Madrid/IdiPAZ and CIBER in Epidemiology and Public Health (CIBERESP), Spain (J.R.B., L.M.R., J.J.d.l.C.); Instituto de Investigación Hospital Doce de Octubre, Madrid, Spain (L.M.R.); Department of Internal Medicine, Hospital Mutua Terrassa, University of Barcelona, Spain (A.d.l.S.); La Mina Primary Care Center, Department of Medicine, University of Barcelona, Spain (E.V.); Nephrology Service, Department of Medicine, Hospital Universitario Central de Asturias, RedinRed, Oviedo, Spain (M.G.); Hypertension Unit, Department of Nephrology, Hospital Doce de Octubre, Madrid, Spain (J.S.); Hypertension Unit, Department of Nephrology, Hospital Universitari del Mar and IMIM (Institut Hospital del Mar d'Investigacions Mèdiques), Barcelona, Spain (A.O.); Hypertension Unit, Department of Medicine, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria del HCSC, Madrid, Spain (N.M.); Cardiometabolic and Hypertension Unit, Department of Medicine, Hospital Universitario La Paz, Universidad Autónoma de Madrid/IdiPAZ, Madrid, Spain (J.G.-P.); and University College London (UCL) Institute of Cardiovascular Science and NIHR UCL Hospitals Biomedical Research Centre, United Kingdom (B.W.).
authors.forename: Anna
authors.initials: A
authors.lastname: Oliveras
authors.affiliation: From the Department of Preventive Medicine and Public Health, Universidad Autónoma de Madrid/IdiPAZ and CIBER in Epidemiology and Public Health (CIBERESP), Spain (J.R.B., L.M.R., J.J.d.l.C.); Instituto de Investigación Hospital Doce de Octubre, Madrid, Spain (L.M.R.); Department of Internal Medicine, Hospital Mutua Terrassa, University of Barcelona, Spain (A.d.l.S.); La Mina Primary Care Center, Department of Medicine, University of Barcelona, Spain (E.V.); Nephrology Service, Department of Medicine, Hospital Universitario Central de Asturias, RedinRed, Oviedo, Spain (M.G.); Hypertension Unit, Department of Nephrology, Hospital Doce de Octubre, Madrid, Spain (J.S.); Hypertension Unit, Department of Nephrology, Hospital Universitari del Mar and IMIM (Institut Hospital del Mar d'Investigacions Mèdiques), Barcelona, Spain (A.O.); Hypertension Unit, Department of Medicine, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria del HCSC, Madrid, Spain (N.M.); Cardiometabolic and Hypertension Unit, Department of Medicine, Hospital Universitario La Paz, Universidad Autónoma de Madrid/IdiPAZ, Madrid, Spain (J.G.-P.); and University College London (UCL) Institute of Cardiovascular Science and NIHR UCL Hospitals Biomedical Research Centre, United Kingdom (B.W.).
authors.forename: Nieves
authors.initials: N
authors.lastname: Martell
authors.affiliation: From the Department of Preventive Medicine and Public Health, Universidad Autónoma de Madrid/IdiPAZ and CIBER in Epidemiology and Public Health (CIBERESP), Spain (J.R.B., L.M.R., J.J.d.l.C.); Instituto de Investigación Hospital Doce de Octubre, Madrid, Spain (L.M.R.); Department of Internal Medicine, Hospital Mutua Terrassa, University of Barcelona, Spain (A.d.l.S.); La Mina Primary Care Center, Department of Medicine, University of Barcelona, Spain (E.V.); Nephrology Service, Department of Medicine, Hospital Universitario Central de Asturias, RedinRed, Oviedo, Spain (M.G.); Hypertension Unit, Department of Nephrology, Hospital Doce de Octubre, Madrid, Spain (J.S.); Hypertension Unit, Department of Nephrology, Hospital Universitari del Mar and IMIM (Institut Hospital del Mar d'Investigacions Mèdiques), Barcelona, Spain (A.O.); Hypertension Unit, Department of Medicine, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria del HCSC, Madrid, Spain (N.M.); Cardiometabolic and Hypertension Unit, Department of Medicine, Hospital Universitario La Paz, Universidad Autónoma de Madrid/IdiPAZ, Madrid, Spain (J.G.-P.); and University College London (UCL) Institute of Cardiovascular Science and NIHR UCL Hospitals Biomedical Research Centre, United Kingdom (B.W.).
authors.forename: Juan
authors.initials: J
authors.lastname: García-Puig
authors.affiliation: From the Department of Preventive Medicine and Public Health, Universidad Autónoma de Madrid/IdiPAZ and CIBER in Epidemiology and Public Health (CIBERESP), Spain (J.R.B., L.M.R., J.J.d.l.C.); Instituto de Investigación Hospital Doce de Octubre, Madrid, Spain (L.M.R.); Department of Internal Medicine, Hospital Mutua Terrassa, University of Barcelona, Spain (A.d.l.S.); La Mina Primary Care Center, Department of Medicine, University of Barcelona, Spain (E.V.); Nephrology Service, Department of Medicine, Hospital Universitario Central de Asturias, RedinRed, Oviedo, Spain (M.G.); Hypertension Unit, Department of Nephrology, Hospital Doce de Octubre, Madrid, Spain (J.S.); Hypertension Unit, Department of Nephrology, Hospital Universitari del Mar and IMIM (Institut Hospital del Mar d'Investigacions Mèdiques), Barcelona, Spain (A.O.); Hypertension Unit, Department of Medicine, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria del HCSC, Madrid, Spain (N.M.); Cardiometabolic and Hypertension Unit, Department of Medicine, Hospital Universitario La Paz, Universidad Autónoma de Madrid/IdiPAZ, Madrid, Spain (J.G.-P.); and University College London (UCL) Institute of Cardiovascular Science and NIHR UCL Hospitals Biomedical Research Centre, United Kingdom (B.W.).
authors.forename: Bryan
authors.initials: B
authors.lastname: Williams
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001794:Blood Pressure / Q000502:physiology*; D018660:Blood Pressure Monitoring, Ambulatory / Q000379:methods*; D005260:Female; D006801:Humans; D006973:Hypertension / Q000453:epidemiology / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D009017:Morbidity / Q000639:trends; D012042:Registries; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012307:Risk Factors; D013030:Spain / Q000453:epidemiology; D055815:Young Adult
keywords: age group; ambulatory blood pressure monitoring; conventional blood pressure; epidemiology; hypertension