DUCS-DHD Determinants of Hypertension in Tanzania
DUCS-DHD Determinants of Hypertension in Tanzania
The aim of the Dar es Salaam Urban Cohort Hypertension Study (DUCS-HTN) was to determine the
 current prevalence, risk factors, and barriers to diagnosis and treatment for hypertension in
 Dar es Salaam, Tanzania. Few previous studies in Tanzania have analyzed the modifiable
 determinants of high BP as well as barriers to diagnosis and treatment of hypertension.

 DUCS-HTN is a cohort of adults living in the Ukonga ward of Dar es Salaam who had been
 registered in the Dar es Salaam Health and Demographic Surveillance System (HDSS) in 2011.
 Due to the large size of Ukonga, the investigators chose to randomly sample two of the seven
 neighborhoods that compose Ukonga and then conducted a census of these two randomly selected
 neighborhoods, Mwembe Madafu and Markazi. The investigators attempted to contact all 4896
 HDSS participants who were at least 40 years of age and lived in one of these neighborhoods.

 Trained interviewers conducted face-to-face interviews and physical examinations in
 participants' homes from March to June 2014. Follow-up visits were conducted from April to
 June 2015.

 Among 4896 potentially eligible participants from the HDSS baseline survey, 3604 (74%) were
 still living at the same address in 2014. Of these, 2290 (64%) enrolled in the DUCS-HTN
 study. Of the participants enrolled at baseline, 1752 (77%) participated in the follow-up
 study.

 Blood pressure measurements

 Trained interviewers measured blood pressure with digital blood pressure monitors (15 Omron
 M2 and 5 Beurer BM 40 monitors). Standard, large, and extra-large cuff sizes were used
 according to the size of a participant's arm. Blood pressure was measured three times with at
 least a 5-minute rest before the first measurement and 3-minute rests between each subsequent
 measurement. Blood pressure was taken on the left arm with the participant seated and the arm
 straight at heart level. Usual blood pressure values were calculated as the mean of the
 second and third readings. If a second visit was conducted, usual blood pressure values were
 defined as the mean of the second and third readings at both the first and second visits.

 Hypertension was defined as SBP≥140 mmHg or DBP≥90 mmHg, or self-reported use of
 anti-hypertensive medication. Grade I hypertension was defined as SBP of 140 to 159 or DBP of
 90 to 99 mmHg; grade II hypertension was defined as SBP of 160 to 179 or DBP of 100 to 109
 mmHg; and grade III hypertension was defined as SBP≥180 or DBP≥110 mmHg. Hypertension control
 was defined as current antihypertensive use and blood pressure of less than 140/90 mmHg. If a
 participant was found to have grade I or II hypertension, a second visit was scheduled, at
 least three days later. Those with grade III hypertension at the last reading of the first
 visit or grade I or II hypertension at the last reading of the second visit were told that
 they had high blood pressure, advised to see a health professional and were given a referral
 letter. In addition, a second visit and blood pressure reading was scheduled for a random
 sample of one-fifth of participants, who were selected for additional blood, urinary, and
 dietary measurements.

 Assessment of covariates

 All participants were administered a socio-demographic and lifestyle questionnaire and had
 their height, weight, and waist and hip circumference measured. Some demographic information
 (age, sex, neighborhood, religion, and assets used to create a household wealth index) was
 previously recorded during the HDSS baseline. Information on household health insurance
 coverage was collected in 2015 as part of routine HDSS updates.

 Standard protocols were used to take anthropometric measurements. Participants were weighed
 with minimal clothing using a digital scale (Seca, Germany) to the nearest 0.1kg and height
 was measured, with participants not wearing shoes, to the nearest 1cm. Body mass index (BMI)
 was calculated as the ratio of weight in kilograms to height in meters squared (kg/m2) and
 categorized according to WHO categories.

 The Global Physical Activity Questionnaire (GPAQ) was used to assess physical activity for
 work, transportation, and leisure. The investigators defined physical inactivity according to
 WHO guidelines. Number of servings of alcoholic beverages consumed was reported over the past
 30 days. The investigators assumed 14 grams of alcohol as a standard drink portion size. A
 household wealth index was created through a principal component analysis of household
 characteristics and assets, and was categorized into quintiles. In the follow-up visit,
 participants were asked about their health over the past year and the reasons for not seeking
 hypertension care.

 A subsample of ~ one fifth of the participants completed a food frequency questionnaire, two
 24-hour dietary recalls, a 24-hour urine collection for sodium, creatinine, protein, and
 potassium, and had capillary total cholesterol and blood glucose measurements taken.
Inclusion Criteria:

 -  Lived in Madafu or Markazi neighborhoods of Ukonga Ward in Tanzania

 Exclusion Criteria:

 -  Pregnant

 -  Mentally or physically disabled