Epidemic Hypertension in Nigerian Workers

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT00005333
Recruitment Status : Completed
First Posted : May 26, 2000
Last Update Posted : May 13, 2016
Information provided by:
National Heart, Lung, and Blood Institute (NHLBI)

Brief Summary:
Originally from 1991 to 1991, to test the hypothesis that differences in hypertension prevalence in Nigerian workers were primarily related to differences in socioeconomic status (SES). At renewal in 1996, to determine the importance of weight gain and weight-related factors in blood pressure.

Condition or disease
Cardiovascular Diseases Heart Diseases Hypertension

Detailed Description:


This dynamic population provided a valuable opportunity to gain important information about the etiology of hypertension which would be much more difficult to gain from a United States Black population because higher weight and blood pressure are already entrenched and static in the United States population.


From 1991 to 1996, a cross-sectional study was conducted to test the hypothesis that differences in hypertension prevalence were primarily related to differences in SES. The higher prevalence of hypertension among the high SES Nigerian professionals was thought to be related to higher weight, caloric intake, Westernization of diet, alcohol intake, sodium intake, cardiovascular reactivity, and stress due to job, migration, and change in SES, and to reduced potassium intake and physical activity. Civil servants were systematically sampled from civil service employee lists. Data were collected on blood pressure; urinary sodium, potassium, and protein; diet; anthropometry; electrocardiogram; serum insulin; stress in the work environment, migration history, and cardiovascular reactivity.

In FY 1992, the Office of Research on Women's Health provided supplemental funds to enlarge the study and to perform gender analyses. The supplemental funds were used to determine whether fatty acid distributions, and their relationships to cardiovascular risk factors differed between Nigerian women and United States Black women; United States Black women and United States white women; and Nigerian women and Nigerian men. Forty men and forty women, ages 18 to 30, were chosen randomly from the Nigerian civil servant population. Subjects with hypertension, those using oral contraceptives, or any medication affecting the sympathetic nervous system, were excluded. The Nigerian subjects were compared with 40 Black and 40 white healthy female volunteers at the University of Pittsburgh.

The grant was renewed in 1996 through August 2001 to conduct a longitudinal study of 726 members of the original cohort. The purpose was to determine the importance of weight gain and weight-related factors, and the possible interaction of other factors, e.g. psychosocial, electrolytes, reactivity, macronutrient intake, to change in blood pressure. Factors related to weight gain were identified. The high prevalence of the electrocardiogram left ventricular hypertrophy (ECG-LVH) was validated against echocardiographic measures (ECHO-LVH). Predictors of change in ECG-LVH, and the correlates of microalbuminuria were identified. In Year 2 (Cohort Year 4) half of the population was restudied with echocardiography, cardiovascular reactivity, and new psychosocial measures. In Year 4 (Cohort Year 6), with the exception of cardiovascular reactivity, the full cohort was re-examined for baseline measures, including multiple blood pressure readings, height, weight, waist, hips, ECG, physical activity, two 24 hour dietary recalls, alcohol intake, menopausal status, psychosocial measures, 24 hour urine for sodium, potassium, creatinine, micro-albuminuria, and fasting serum for lipids, insulin, glucose, and creatinine.

The study completion date listed in this record was obtained from the "End Date" entered in the Protocol Registration and Results System (PRS) record.

Study Type : Observational
Study Start Date : January 1991
Actual Study Completion Date : August 2001

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

Ages Eligible for Study:   up to 100 Years   (Child, Adult, Older Adult)
Sexes Eligible for Study:   Male
Accepts Healthy Volunteers:   No
No eligibility criteria

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT00005333

Sponsors and Collaborators
National Heart, Lung, and Blood Institute (NHLBI)
OverallOfficial: Clareann Bunker University of Pittsburgh

Publications: Identifier: NCT00005333     History of Changes
Other Study ID Numbers: 4188
R01HL044413 ( U.S. NIH Grant/Contract )
First Posted: May 26, 2000    Key Record Dates
Last Update Posted: May 13, 2016
Last Verified: August 2004

Additional relevant MeSH terms:
Cardiovascular Diseases
Heart Diseases
Vascular Diseases