Clinical trial NCT00005271: INTERMAP: International Population Study on Macronutrients and BP
Official title: INTERMAP: International Population Study on Macronutrients and BP
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Cardiovascular Diseases
Heart Diseases
Hypertension
Lead sponsor: Northwestern University
Sponsor class: OTHER
Collaborators: name: National Heart, Lung, and Blood Institute (NHLBI)
First posted: 2000-05-26
Enrollment: 4680
Sex: ALL
Minimum age (years): 40
Maximum age (years): 59
Standard ages: ADULT
Accepts healthy volunteers: no
Observational model: COHORT
Time perspective: CROSS_SECTIONAL
Sampling method: PROBABILITY_SAMPLE
Study population: The INTERMAP study population includes 4,680 men and women ages 40-59 who were recruited from 17 population samples of diverse ethnicity/ SES/ eating practices in four countries (China, Japan, UK, USA).

Brief summary: To investigate the relationship between dietary factors, especially macronutrients, and blood pressure in an international, multicenter observational study. A particular focus is to help elucidate the role of these dietary factors in accounting for the even more adverse blood pressure patterns of less educated population strata, especially in the United States, in both less educated Blacks and whites.

Detailed description: BACKGROUND:

Overall study findings are to be used to estimate favorable impact on blood pressure of multiple improvements in nutrition by populations. The investigators state that this should aid in making additional dietary recommendations toward the goal of primary prevention of hypertension and shifting blood pressure distributions downward to avoid excess risk associated with present levels generally above optimal.

DESIGN NARRATIVE:

INTERMAP's cross-sectional design is patterned after the tested INTERSALT model: a large sample size of 4,680 persons, half men and half women, ages 40-59 from 17 population samples of varied ethnicity, socioeconomic status (SES) and dietary habits in four countries (China, Japan, United Kingdom and the United States). There were eight United States INTERMAP centers. Specific aims involve elucidating influences on blood pressure of the amount and type of protein, lipids, carbohydrates, and also amino acids, calcium, magnesium, antioxidants, fiber, and caffeine. Primary hypotheses tested, with control for body mass index (BMI), intake of alcohol, age, sex, and other confounders are as follow: dietary protein is inversely related to blood pressure; inverse relations between education and blood pressure are significantly accounted for by education-related differences in dietary protein intake; there is a direct relation to blood pressure of dietary saturated fatty acids, cholesterol, Keys score, starch; there is an inverse relation of polyunsaturated fatty acids and polyunsaturated/saturated fatty acids. Randomly selected participants provide one timed 24-hr. urine collection for assessment of sodium, potassium, creatine, and urea, and complete four 24-hr. dietary recalls. Blood pressure was measured eight times at each of four clinic visits, with standardization and strict quality control of all procedures.

The study is coordinated by two Coordinating Centers--Northwestern University, Chicago and London School of Hygiene \& Tropical Medicine. Urinary determinations are made at a Central Laboratory in Leuven, Belgium. Twenty-four hour dietary recalls are converted into nutrients with use of the Nutrition Data System of the University of Minnesota's Nutrition Coordinating Center. Data analyses to test hypotheses are done at the London Coordinating Center.

Recruitment and data collection began in July, 1996 through January, 1997. The main statistical analytic method is multivariate regression analysis. The study was renewed in FY 2000 and in FY 2004 to continue analysis of the data through August, 2009.

Eligibility criteria: Inclusion Criteria:

* Healthy individuals
* Men and women
* Age 40-59 years
* Willing to collect 24 hour urine and return to clinic for second follow-up visit

Exclusion Criteria:

* Existing disease
* Unwilling to provide 24 hour urine collections
* Unable to attend follow-up visits
* Unable to recall dietary intake

Primary outcomes:
measure: Blood pressure measurement relative to diet.
timeFrame: 15 years
Secondary outcomes:
Other outcomes:
Locations:
Study officials:
affiliation: Johns Hopkins University
name: Lawrence Appel
role: PRINCIPAL_INVESTIGATOR
affiliation: University of Mississippi Medical Center
name: Daniel Jones
role: PRINCIPAL_INVESTIGATOR
affiliation: University of Texas
name: Darwin Labarthe
role: PRINCIPAL_INVESTIGATOR
affiliation: University of Hawaii at Manoa
name: Beatriz Rodriguez
role: PRINCIPAL_INVESTIGATOR
affiliation: Northwestern University
name: Jeremiah Stamler
role: PRINCIPAL_INVESTIGATOR
affiliation: Northwestern University
name: Linda Van Horn
role: PRINCIPAL_INVESTIGATOR
References:
citation: Stamler J, Elliott P, Dennis B, Dyer AR, Kesteloot H, Liu K, Ueshima H, Zhou BF; INTERMAP Research Group. INTERMAP: background, aims, design, methods, and descriptive statistics (nondietary). J Hum Hypertens. 2003 Sep;17(9):591-608. doi: 10.1038/sj.jhh.1001603.
citation: Beevers DG, Stamler J. Background to the INTERMAP study of nutrients and blood pressure. J Hum Hypertens. 2003 Sep;17(9):589-90. doi: 10.1038/sj.jhh.1001609. No abstract available.
citation: Dennis B, Stamler J, Buzzard M, Conway R, Elliott P, Moag-Stahlberg A, Okayama A, Okuda N, Robertson C, Robinson F, Schakel S, Stevens M, Van Heel N, Zhao L, Zhou BF; INTERMAP Research Group. INTERMAP: the dietary data--process and quality control. J Hum Hypertens. 2003 Sep;17(9):609-22. doi: 10.1038/sj.jhh.1001604.
citation: Zhou BF, Stamler J, Dennis B, Moag-Stahlberg A, Okuda N, Robertson C, Zhao L, Chan Q, Elliott P; INTERMAP Research Group. Nutrient intakes of middle-aged men and women in China, Japan, United Kingdom, and United States in the late 1990s: the INTERMAP study. J Hum Hypertens. 2003 Sep;17(9):623-30. doi: 10.1038/sj.jhh.1001605.
citation: Dyer AR, Elliott P, Stamler J, Chan Q, Ueshima H, Zhou BF; INTERMAP Research Group. Dietary intake in male and female smokers, ex-smokers, and never smokers: the INTERMAP study. J Hum Hypertens. 2003 Sep;17(9):641-54. doi: 10.1038/sj.jhh.1001607.
citation: Stamler J, Elliott P, Appel L, Chan Q, Buzzard M, Dennis B, Dyer AR, Elmer P, Greenland P, Jones D, Kesteloot H, Kuller L, Labarthe D, Liu K, Moag-Stahlberg A, Nichaman M, Okayama A, Okuda N, Robertson C, Rodriguez B, Stevens M, Ueshima H, Horn LV, Zhou B. Higher blood pressure in middle-aged American adults with less education-role of multiple dietary factors: the INTERMAP study. J Hum Hypertens. 2003 Sep;17(9):655-775. doi: 10.1038/sj.jhh.1001608.
citation: Conway R, Robertson C, Dennis B, Stamler J, Elliott P; INTERMAP Research Group. Standardised coding of diet records: experiences from INTERMAP UK. Br J Nutr. 2004 May;91(5):765-71. doi: 10.1079/BJN20041095.
citation: Zhao L, Stamler J, Yan LL, Zhou B, Wu Y, Liu K, Daviglus ML, Dennis BH, Elliott P, Ueshima H, Yang J, Zhu L, Guo D; INTERMAP Research Group. Blood pressure differences between northern and southern Chinese: role of dietary factors: the International Study on Macronutrients and Blood Pressure. Hypertension. 2004 Jun;43(6):1332-7. doi: 10.1161/01.HYP.0000128243.06502.bc. Epub 2004 Apr 26.
citation: Dyer AR, Greenland P, Elliott P, Daviglus ML, Claeys G, Kesteloot H, Chan Q, Ueshima H, Stamler J; INTERMAP Research Group. Estimating laboratory precision of urinary albumin excretion and other urinary measures in the International Study on Macronutrients and Blood Pressure. Am J Epidemiol. 2004 Aug 1;160(3):287-94. doi: 10.1093/aje/kwh196.
citation: Dyer AR, Greenland P, Elliott P, Daviglus ML, Claeys G, Kesteloot H, Ueshima H, Stamler J; INTERMAP Research Group. Evaluation of measures of urinary albumin excretion in epidemiologic studies. Am J Epidemiol. 2004 Dec 1;160(11):1122-31. doi: 10.1093/aje/kwh326.
citation: Daviglus ML, Greenland P, Stamler J, Elliott P, Appel LJ, Carnethon MR, Chan Q, Claeys G, Kesteloot H, Miura K, Nakagawa H, Pirzada A, Steffen L, Yan LL, Zhou B, Dyer AR. Relation of nutrient intake to microalbuminuria in nondiabetic middle-aged men and women: International Population Study on Macronutrients and Blood Pressure (INTERMAP). Am J Kidney Dis. 2005 Feb;45(2):256-66. doi: 10.1053/j.ajkd.2004.11.005.
citation: Elliott P, Stamler J, Dyer AR, Appel L, Dennis B, Kesteloot H, Ueshima H, Okayama A, Chan Q, Garside DB, Zhou B. Association between protein intake and blood pressure: the INTERMAP Study. Arch Intern Med. 2006 Jan 9;166(1):79-87. doi: 10.1001/archinte.166.1.79.
citation: Salman E, Kadota A, Okami Y, Kondo K, Yoshita K, Okuda N, Nakagawa H, Saitoh S, Sakata K, Okayama A, Chan Q, Elliott P, Stamler J, Ueshima H, Miura K; INTERMAP Research Group. Investigation of the urinary sodium-to-potassium ratio target level based on the recommended dietary intake goals for the Japanese population: The INTERMAP Japan. Hypertens Res. 2022 Dec;45(12):1850-1860. doi: 10.1038/s41440-022-01007-x. Epub 2022 Nov 8.
citation: Chan Q, Wren GM, Lau CE, Ebbels TMD, Gibson R, Loo RL, Aljuraiban GS, Posma JM, Dyer AR, Steffen LM, Rodriguez BL, Appel LJ, Daviglus ML, Elliott P, Stamler J, Holmes E, Van Horn L. Blood pressure interactions with the DASH dietary pattern, sodium, and potassium: The International Study of Macro-/Micronutrients and Blood Pressure (INTERMAP). Am J Clin Nutr. 2022 Jul 6;116(1):216-229. doi: 10.1093/ajcn/nqac067.
citation: Aljuraiban G, Chan Q, Gibson R, Stamler J, Daviglus ML, Dyer AR, Miura K, Wu Y, Ueshima H, Zhao L, Van Horn L, Elliott P, Oude Griep LM; INTERMAP Research Group. Association between plant-based diets and blood pressure in the INTERMAP study. BMJ Nutr Prev Health. 2020 Jul 8;3(2):133-142. doi: 10.1136/bmjnph-2020-000077. eCollection 2020 Dec.
citation: Gibson R, Lau CE, Loo RL, Ebbels TMD, Chekmeneva E, Dyer AR, Miura K, Ueshima H, Zhao L, Daviglus ML, Stamler J, Van Horn L, Elliott P, Holmes E, Chan Q. The association of fish consumption and its urinary metabolites with cardiovascular risk factors: the International Study of Macro-/Micronutrients and Blood Pressure (INTERMAP). Am J Clin Nutr. 2020 Feb 1;111(2):280-290. doi: 10.1093/ajcn/nqz293.
citation: Zhou L, Stamler J, Chan Q, Van Horn L, Daviglus ML, Dyer AR, Miura K, Okuda N, Wu Y, Ueshima H, Elliott P, Zhao L; INTERMAP Research Group. Salt intake and prevalence of overweight/obesity in Japan, China, the United Kingdom, and the United States: the INTERMAP Study. Am J Clin Nutr. 2019 Jul 1;110(1):34-40. doi: 10.1093/ajcn/nqz067.
citation: Wen X, Zhou L, Stamler J, Chan Q, Van Horn L, Daviglus ML, Dyer AR, Elliott P, Ueshima H, Miura K, Okuda N, Wu Y, Zhao L. Agreement between 24-h dietary recalls and 24-h urine collections for estimating sodium intake in China, Japan, UK, USA: the International Study of Macro- and Micro-nutrients and Blood Pressure. J Hypertens. 2019 Apr;37(4):814-819. doi: 10.1097/HJH.0000000000001941.
citation: Stamler J, Chan Q, Daviglus ML, Dyer AR, Van Horn L, Garside DB, Miura K, Wu Y, Ueshima H, Zhao L, Elliott P; INTERMAP Research Group. Relation of Dietary Sodium (Salt) to Blood Pressure and Its Possible Modulation by Other Dietary Factors: The INTERMAP Study. Hypertension. 2018 Apr;71(4):631-637. doi: 10.1161/HYPERTENSIONAHA.117.09928.
citation: Aljuraiban GS, Chan Q, Oude Griep LM, Brown IJ, Daviglus ML, Stamler J, Van Horn L, Elliott P, Frost GS; INTERMAP Research Group. The impact of eating frequency and time of intake on nutrient quality and Body Mass Index: the INTERMAP Study, a Population-Based Study. J Acad Nutr Diet. 2015 Apr;115(4):528-36.e1. doi: 10.1016/j.jand.2014.11.017. Epub 2015 Jan 22.
citation: Chan Q, Stamler J, Brown IJ, Daviglus ML, Van Horn L, Dyer AR, Oude Griep LM, Miura K, Ueshima H, Zhao L, Nicholson JK, Holmes E, Elliott P; INTERMAP Research Group. Relation of raw and cooked vegetable consumption to blood pressure: the INTERMAP Study. J Hum Hypertens. 2014 Jun;28(6):353-9. doi: 10.1038/jhh.2013.115. Epub 2013 Nov 21.
citation: Stamler J, Brown IJ, Yap IK, Chan Q, Wijeyesekera A, Garcia-Perez I, Chadeau-Hyam M, Ebbels TM, De Iorio M, Posma J, Daviglus ML, Carnethon M, Holmes E, Nicholson JK, Elliott P; INTERMAP Research Group. Dietary and urinary metabonomic factors possibly accounting for higher blood pressure of black compared with white Americans: results of International Collaborative Study on macro-/micronutrients and blood pressure. Hypertension. 2013 Dec;62(6):1074-80. doi: 10.1161/HYPERTENSIONAHA.113.01810. Epub 2013 Oct 7.
citation: Oude Griep LM, Stamler J, Chan Q, Van Horn L, Steffen LM, Miura K, Ueshima H, Okuda N, Zhao L, Daviglus ML, Elliott P; INTERMAP Research Group. Association of raw fruit and fruit juice consumption with blood pressure: the INTERMAP Study. Am J Clin Nutr. 2013 May;97(5):1083-91. doi: 10.3945/ajcn.112.046300. Epub 2013 Apr 3.