Sodium reduction and weight loss lead to decreased blood pressure (BP). Among hypertensives, BP lowering leads to decreased risk of MI, stroke, and cardiovascular death. Nonetheless, concerns have been raised about increased numbers of cardiovascular events among individuals with low sodium intake or large weight changes. The proposed prospective observational follow-up of the Trials of Hypertension Prevention (TOHP) will include cardiovascular events among the 4, 507 surviving participants from the ten clinical centers involved in Phases I and II of TOHP. Phase I was a randomized trial of the effects of seen non- pharmacologic interventions, including sodium reduction and weight loss, on BP over 18 months of follow-up with 2,182 participants. Phase II examined the effects of sodium reduction and weight loss on BP over a longer 36-month period in a randomized 2X2 factorial design with 2,382 participants. During follow-up in Phases I and II of TOHP, several measures of both weight and sodium excretion were carefully obtained on all participants. The proposed prospective observational follow-up will specifically examine whether these values, with an emphasis on average level of sodium excretion and weight changes are predictive of later cardiovascular disease. The follow-up will be conducted centrally by mail from the Division of Preventive Medicine, which served as the Coordinating Center for Phases I and II, and which has been very successful in conducting such large-scale studies by mail. Information on cardiovascular events subsequent to the trial periods will be collected through June, 2003, representing an average follow-up of approximately fourteen years from the end of Phase I and eight years from the end of Phase II. This cohort provides a unique resource to address the impact in a normotensive population of salt restriction and weight change on subsequent cardiovascular events.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Research Project (R01)
Project #
5R01HL057915-02
Application #
6183907
Study Section
Special Emphasis Panel (ZRG1-HPD (09))
Project Start
1999-09-01
Project End
2004-08-31
Budget Start
2000-09-01
Budget End
2001-08-31
Support Year
2
Fiscal Year
2000
Total Cost
$259,150
Indirect Cost
Name
Brigham and Women's Hospital
Department
Type
DUNS #
071723621
City
Boston
State
MA
Country
United States
Zip Code
02115
Cook, Nancy R; Appel, Lawrence J; Whelton, Paul K (2018) Weight change and mortality: Long-term results from the trials of hypertension prevention. J Clin Hypertens (Greenwich) 20:1666-1673
Cook, Nancy R; Appel, Lawrence J; Whelton, Paul K (2016) Sodium Intake and All-Cause Mortality Over 20 Years in the Trials of Hypertension Prevention. J Am Coll Cardiol 68:1609-1617
Cook, Nancy R; Appel, Lawrence J; Whelton, Paul K (2014) Lower levels of sodium intake and reduced cardiovascular risk. Circulation 129:981-9
Cook, Nancy R; Obarzanek, Eva; Cutler, Jeffrey A et al. (2009) Joint effects of sodium and potassium intake on subsequent cardiovascular disease: the Trials of Hypertension Prevention follow-up study. Arch Intern Med 169:32-40
Cook, Nancy R (2008) Salt intake, blood pressure and clinical outcomes. Curr Opin Nephrol Hypertens 17:310-4
Cook, Nancy R; Cutler, Jeffrey A; Obarzanek, Eva et al. (2007) Long term effects of dietary sodium reduction on cardiovascular disease outcomes: observational follow-up of the trials of hypertension prevention (TOHP). BMJ 334:885-8
Cook, N R (2006) Imputation strategies for blood pressure data nonignorably missing due to medication use. Clin Trials 3:411-20