Coronary heart disease risk factors in sub-Saharan Africa: studies in Tanzanian adolescents

Hypertension among adolescents in sub-Saharan Africa: a systematic review

Introduction

Hypertension (HTN) among adolescents is common in high-income countries, and leads to increased premature cardiovascular diseases (CVD). In sub-Saharan Africa (SSA), the prevalence of HTN among adolescents, associated risk factors and CVD complications are not well-described. Such data is needed for planning public health programs to prevent premature CVD in SSA.

Methods

We systematically searched 5 databases (MEDLINE, Embase, Google Scholar, Web of Science, and African Index Medicus) from their establishment to December 2021. Key search terms were: adolescent, arterial hypertension, and names of the 48 countries in SSA. We used Covidence® to manage the search results. The review was registered in the Open Science Framework (OSF) https://osf.io/p5sbt/.

Results

We identified 4,008 articles out of which we screened 3,088 abstracts, and reviewed 583 full-text articles. We finally included 92 articles that were published between 1968 to December 2021. The majority were cross-sectional studies (80%) and conducted in school settings (78%). The risk of bias was low for 59 studies (64.1%), moderate for 29 studies (31.5%), and high for 4 studies (4.3%). Overall, the prevalence of HTN varied widely from 0.18% to 34.0% with a median (IQR) of 5.5% (3.1%, 11.1%). It was relatively higher in studies using automated blood pressure (BP) devices, and in studies defining HTN using thresholds based on percentile BP distribution for one's height, age, and sex. In addition, the prevalence of HTN was significantly higher in studies from Southern Africa region of SSA and positively correlated with the year of publication. Across studies, traditional risk factors such as age, sex, body mass index, and physical inactivity, were commonly found to be associated with HTN. In contrast, non-traditional risk factors related to poverty and tropical diseases were rarely assessed. Only three studies investigated the CVD complications related to HTN in the study population.

Conclusion

The prevalence of HTN among adolescents in SSA is high indicating that this is a major health problem. Data on non-traditional risk factors and complications are scarce. Longitudinal studies are needed to clearly define the rates, causes, and complications of HTN.

Systematic Review Registration

https://osf.io/p5sbt/, identifier (10.17605/OSF.IO/P5SBT).

Acute Coronary Syndromes Due to Atherosclerotic Coronary Artery Disease in Young Patients

Young patients represent about 4-10% of the population presenting with acute coronary syndrome. In this focused mini-review, we highlight the data regarding acute coronary syndromes in young patients with atherosclerotic coronary artery disease. Differences in the underlying pathologies and pathophysiological mechanisms should yield to different clinical management and treatment strategies.

Blood Cholesterol and Triglycerides in Adolescent Egyptian Girls: Relation to Anthropometric Measurements

High serum cholesterol is a major risk factor for atherosclerosis. This cross-sectional study (n = 102) investigated the levels of total cholesterol (TC) and triglycerides (TG) in Egyptian girls aged 11 to 16 years attending a middle-class public school. The mean TC level was 194.27 ± 21.97 mg/dl, and 33.33% of girls had TC levels > 200 mg/dl. The mean TG level was 160.07 ± 30.83 mg/dl, with 3.92% of the girls showing TG levels > 2 00 mg/dl. Most of the girls (65.69%) were overweight, with body mass index (BMI) >25. Univariate analyses revealed an association of TC and TG with all anthropometric measures. Using stepwise regression analyses, the best model for prediction of TC was with BMI and central body fat (explaining 24.76% of TC variance); the final model for TG was with BMI, central body fat, and abdominal skinfold thickness (explaining 47.49% of TG variance). Our data show that these adolescent Egyptian girls were heavier and had higher blood lipid concentrations than subjects in the Bogalusa study and other studies worldwide. Further studies are needed to determine the factors associated with these higher lipid levels and to develop appropriate intervention programmes.

Effect of training community health workers and their interventions on cardiovascular disease risk factors among adults in Morogoro, Tanzania: study protocol for a cluster randomized controlled trial

BACKGROUND

Cardiovascular diseases (CVDs) increasingly contribute to morbidity and mortality in Tanzania. Public knowledge about CVD risk factors is important for the primary prevention of CVDs and can be improved through community-based interventions delivered by community health workers (CHWs). However, evidence of the utility of CHWs in improving knowledge and CVD risk factors profile is lacking in Tanzania. This study aims at assessing the effect of training CHWs and their CVD-specific interventions for reduction of hypertension and other CVD risk factors among adults in Morogoro, Tanzania.

METHODS

This study will use a mixed-methods design with both quantitative and qualitative approaches. A baseline quantitative survey will be conducted to assess knowledge, prevalence, and determinants of CVD risk factors in a random sample of 2950 adults aged 25-64 years. A cluster randomized controlled design with pre-test will be used to assess the effects of CVD-specific interventions delivered by CHWs on reduction of blood pressure and proportion of other CVD risk factors among 516 adults with raised blood pressure from 12 randomly selected villages in Morogoro, Tanzania. Focus group discussion (FGDs) will be conducted at the end of the intervention to assess perceived quality and acceptability of CVD-specific interventions delivered by CHWs. The intervention will consist of a five-day CVD-specific training to CHWs from villages randomized to the intervention. Trained CHWs will then provide home health education and healthy lifestyle promotion for prevention of CVD risk factors, counseling about hypertension screening for early identification, and referral and linkage of individuals with elevated blood pressure to health facilities. Since intensity of the intervention is key to reinforce behavior change, CHWs will visit the participants every month for the first six months, then bi-monthly thereafter up to 12 months. Except for referral of participants with raised blood pressure identified during the baseline survey, control villages will not receive any interventions delivered by CHWs. At the end of the intervention period, an end-line survey will be conducted in both intervention and control villages to evaluate changes in knowledge, blood pressure, and proportion of other CVD risk factors.

DISCUSSION

The results of this study are likely to have positive policy implications for the prevention of CVD risk factors through the use of CHWs in the provision of CVD-specific interventions, especially now that the Tanzanian government is considering implementing and scaling up a nation-wide multitask CHW cadre.

TRIAL REGISTRATION

PACTR Registry, PACTR201801002959401 . Registered on 10 January 2018.

Prevalence and patterns of cigarette smoking among patients co-infected with human immunodeficiency virus and tuberculosis in Tanzania

INTRODUCTION

Cigarette smoking is one of the major risk factors for non-AIDS related morbidities and is highly prevalent among HIV infected people. However, no reports exist from Tanzania, one of the countries highly affected by the HIV pandemic and one of Africa's biggest tobacco producer.

METHODS

We examined the patterns and prevalence of cigarette smoking among HIV and TB co-infected adult patients in Dar es Salaam using a cross sectional study design. Proportions were used to describe the pattern of cigarette smoking. Logistic regression was used to assess the association of various participant characteristics with smoking.

RESULTS

Out of the 518 participants, 17 (3.3%) were current smokers, 96 (18.5%) were ex-smokers and the rest (78.2%) denied ever smoking. Male sex (p<0.001), alcohol (p<0.001), and illicit substance use (p<0.001) were significantly associated with cigarette smoking.

CONCLUSIONS

The study indicates that, the level of current cigarette smoking among HIV/TB co-infected patients in Dar es Salaam is low. Nevertheless, the preponderance of cigarette smoking among men, alcohol drinkers, and those who use illicit substances provides a unique opportunity for targeting such population with smoking cessation interventions; HIV care and treatment clinics are uniquely positioned to provide such interventions.

The Epidemiology of Alcohol Use and Alcohol Use Disorders among Young People in Northern Tanzania

INTRODUCTION

Alcohol use is a global public health problem, including as a risk factor for HIV infection, but few data are available on the epidemiology of alcohol use and alcohol use disorders (AUD) among young people in sub-Saharan Africa.

METHODS

We conducted a cross-sectional survey among 4 groups of young people aged 15-24 years old (secondary school students, college/university students, employees of local industries and casual labourers) in two regions (Kilimanjaro and Mwanza) of northern Tanzania. Using a multistage stratified random sampling strategy, we collected information on demographics, alcohol use, and behavioural factors. We screened severity of alcohol use using the Alcohol Use Disorder Identification Test (AUDIT) and estimated the quantity and frequency of alcohol consumption using the timeline-follow-back-calendar (TLFB) method.

RESULTS

A total of 1954 young people were surveyed. The prevalence of reported alcohol use was higher among males (47-70% ever users and 20-45% current users) than females (24-54% ever users and 12-47% current users). Prevalence of use was substantially higher in Kilimanjaro than Mwanza region. In both regions, participants reported high exposure to alcohol advertisements, and wide alcohol availability. College students reported the highest prevalence of current alcohol use (45% among males; 26% among females) and of heavy episodic drinking (71% among males; 27% among females) followed by casual labourers. Males were more likely to have AUD (an AUDIT score ≥8) than females, with 11-28% of males screening positive for AUD. Alcohol use was associated with male gender, being in a relationship, greater disposable income, non-Muslim religion and a higher number of sexual partners.

CONCLUSIONS

Alcohol use is a significant problem among young people in northern Tanzania. There is an urgent need to develop, pilot and deliver interventions to help young people delay initiation and reduce levels of harmful drinking, particularly among college students and casual labourers.

Association between body fat composition and blood pressure level among secondary school adolescents in Dar es Salaam, Tanzania

INTRODUCTION

Excess body fat and high blood pressure (BP) are important risk factors for increased cardiovascular morbidity and mortality, and both may have their roots of occurrence in childhood and adolescence. The present study aimed at determining the association between body fat composition and BP level among adolescents in Tanzania.

METHODS

A cross-sectional study involving 5 randomly selected secondary schools within Dar es Salaam was conducted between June and November 2013. Structured questionnaires were used to collect information on demographic characteristics and other cardiovascular risk factors. BP, height, weight and waist circumference were measured following standard methods. Body fat was assessed by skinfold thickness and categorized as underfat, healthy, overfat or obese according to World Health Organization definitions. Hypertension was defined as BP ≥ 90(th) percentile for age, height and gender of the adolescent.

RESULTS

The study included 582 adolescents (mean age 16.5 ± 1.8 years, 52.1% boys). The proportion of adolescents with overfat or obesity was 22.2%. Systolic, diastolic and combined hypertension was present in 17.5%, 5.5%, and 4.0% respectively. In the total population mean body fat percent correlated positively with diastolic BP and mean arterial pressure (MAP) but not with systolic BP. In multivariate analysis body mass index (β=0.21, p=0.008) and waist circumference (β=0.12, p=0.049), but not body fat percentage (β=-0.09, p=0.399) independently predicted higher MAP.

CONCLUSION

Body mass index predicts BP level better than body fat composition and should be used as a measure of increased risk for hypertension among adolescents.

Systematic review and meta-analysis: prevalence of alcohol use among young people in eastern Africa

Objective

Systematic review and meta-analysis of published studies of alcohol use among young people (age 15–24 years) in eastern Africa to estimate prevalence of alcohol use and determine the extent of use of standardised screening questionnaires in alcohol studies.

Methods

Five databases (MEDLINE, EMBASE, Global Health, Africa-wide, and PsycINFO) were searched for publications until 30th June 2013. Results were summarised using the guidelines on preferred reporting items for systematic reviews and meta-analyses (PRISMA) and on quality assessment using the modified quality assessment tool for systematic reviews of observational studies (QATSO). Heterogeneity was assessed using the I² statistic (DerSimonian-Laird).

Results

We identified 2785 potentially relevant studies, of which 56 were eligible for inclusion. Only two studies (4%) used the standardised Alcohol Use Disorder Identification Test (AUDIT) questionnaire, and six studies (13%) used the Cut down, Annoyed, Guilt, Eye opener (CAGE) questionnaire. The reported median prevalence of alcohol use was ever-use 52% [interquartile range (IQR): 20–58%], use in the last month 28% (IQR: 17–37%), use in the last year 26% (IQR: 22–32%), and problem drinking as defined by CAGE or AUDIT 15% (IQR: 3–36%). We observed high heterogeneity between studies, with the highest prevalence of ever use of alcohol among university students (82%; 95%CI: 79–85%) and female sex workers (66%; 95%CI: 58–74%). Current use was most prevalent among male sex workers (69%; 95%CI: 63–75%).

Conclusions

Reported alcohol use and problem drinking were common among diverse groups of young people in eastern Africa, indicating the urgent need for alcohol-focused interventions in this population. Few studies have used standardised alcohol screening questionnaires. Epidemiological research to investigate alcohol-focused interventions in young people should aim to apply such questionnaires that should be validated for use in this population.

Epidemiology of ischaemic heart disease in sub-Saharan Africa

BACKGROUND

The epidemiology of ischaemic heart disease (IHD) in sub-Saharan Africa (SSA) remains largely enigmatic. Major obstacles to our understanding of the condition include lack of reliable health statistics, particularly cause-specific mortality data, inadequate diagnostic capabilities, shortage of physicians and cardiologists, and misguided opinions.

METHODS

This review of the epidemiology of ischaemic heart disease in sub-Saharan Africa involved a systematic bibliographic MEDLINE search of published data on IHD in SSA over the past century. Search words included epidemiology, ischaemic (coronary) heart disease, myocardial infarction, cardiovascular risk factors and sub-Saharan Africa. Selected data are presented on the prevalence of cardiovascular risk factors and mortality from ischaemic heart disease from different countries representing the main regions of the continent.

RESULTS

Although IHD in SSA remains relatively uncommon, its prevalence is predicted to rise in the next two decades due to the rising prevalence of risk factors, especially hypertension, diabetes, overweight and obesity, physical inactivity, increased tobacco use and dyslipidaemia. It is estimated that age-standardised mortality rates for IHD will rise by 27% in African men and 25% in women by 2015, and by 70 and 74%, respectively by 2030.

CONCLUSION

Ischaemic heart disease remains relatively uncommon in SSA, despite an increasing prevalence of risk factors, but its incidence is rising. The pace and direction of economic development, rates of urbanisation, and changes in life expectancy resulting from the impact of pre-transitional diseases and violence will be major determinants of the IHD epidemic in SSA. The best window of opportunity for prevention of the emerging epidemic of ischaemic heart disease in sub-Saharan Africa is now.

Physical activity, fitness and the metabolic syndrome in rural youths from Mozambique

BACKGROUND

Except for North America and Europe, few studies have reported the association among physical activity (PA), cardiorespiratory fitness (CRF) and metabolic syndrome (MetS) in youths, especially for rural African youth.

AIM

The aims of this study were to determine the prevalence of PA levels, CRF, MetS and its indicators, and examine the association between these variables in a school-aged sample of youth from rural Mozambique.

SUBJECTS AND METHODS

The sample included 209 children and adolescents aged 7-15 years old from Calanga, a rural community in Mozambique. PA was estimated with a culturally-specific questionnaire. CRF was determined by 1-mile run test. Indicators of the MetS included fasting glucose, triglycerides, total cholesterol, blood pressure and body mass index. A continuous metabolic risk score was computed.

RESULTS

Results showed high levels of PA and CRF and a low prevalence of MetS ( < 2%) among children and adolescents from Calanga. However, there was a moderately high prevalence of elevated blood pressure (81.8%) and triglycerides (18.7%), respectively. There were no significant associations between PA, CRF and MetS.

CONCLUSION

Youths from Calanga are physically active and possess high CRF and their lifestyle may be a protective effect against MetS.

Non-communicable diseases in sub-Saharan Africa: what we know now

BACKGROUND

Sub-Saharan Africa (SSA) has a disproportionate burden of both infectious and chronic diseases compared with other world regions. Current disease estimates for SSA are based on sparse data, but projections indicate increases in non-communicable diseases (NCDs) caused by demographic and epidemiologic transitions. We review the literature on NCDs in SSA and summarize data from the World Health Organization and International Agency for Research on Cancer on the prevalence and incidence of cardiovascular diseases, diabetes mellitus Type 2, cancer and their risk factors.

METHODS

We searched the PubMed database for studies on each condition, and included those that were community based, conducted in any SSA country and reported on disease or risk factor prevalence, incidence or mortality.

RESULTS

We found few community-based studies and some countries (such as South Africa) were over-represented. The prevalence of NCDs and risk factors varied considerably between countries, urban/rural location and other sub-populations. The prevalence of stroke ranged from 0.07 to 0.3%, diabetes mellitus from 0 to 16%, hypertension from 6 to 48%, obesity from 0.4 to 43% and current smoking from 0.4 to 71%. Hypertension prevalence was consistently similar among men and women, whereas women were more frequently obese and men were more frequently current smokers.

CONCLUSIONS

The prevalence of NCDs and their risk factors is high in some SSA settings. With the lack of vital statistics systems, epidemiologic studies with a variety of designs (cross-sectional, longitudinal and interventional) capable of in-depth analyses of risk factors could provide a better understanding of NCDs in SSA, and inform health-care policy to mitigate the oncoming NCD epidemic.

Risk factors for non-communicable diseases among older adults in rural Africa

OBJECTIVE

To expand the evidence base on the prevalence of non-communicable disease (NCD) risk factors in rural Africa, in particular among older adults aged 50 and older.

METHODS

Cross-sectional study in three rural sites in Malawi, Rwanda and Tanzania. One person was interviewed from each of 665 households selected through a stratified random sampling procedure across the three sites. The questionnaire included socio-demographic characteristics, smoking and alcohol intake as well as a food frequency questionnaire.

RESULTS

Smoking rates among older men and women were higher than among adults under 50. While only 2.3% of women under 50 were current smokers, 21.0% of older women smoked (P<0.0001). Among men, 19.0% of men under 50 smoked versus 36.6% of older men (P=0.001). Alcohol consumption among older women aged 50 and older (45.0%) was more common (P=0.005) than among women under 50 (27.6%). Examining a set of five risk factors, more men aged 50 and older (49.5%) had two or more risk factors than men under 50 (25.5%) (P<0.0001). Similarly, 52.0% of women aged 50 and older had two or more risk factors, versus 24.1% of women under 50 (P<0.0001).

CONCLUSION

Contrary to what is seen in developed country settings, this study reveals high rates of smoking and alcohol consumption among men and women aged 50 years and older in rural Africa that puts them at risk of NCDs. The health of older adults in rural Africa has been neglected, and these findings highlight the importance of reaching out to older adults with messaging regarding diet, smoking, alcohol use and general health.

Prevalence of alcohol consumption and hazardous drinking, tobacco and drug use in urban Tanzania, and their associated risk factors

Evidence suggests substance abuse in Tanzania is a growing public health problem. A random sample of 899 adults aged 15–59 in two urban sites of differing levels of poverty surveyed alcohol, tobacco and illicit substance use. Rates of substance use were 17.2%. 8.7% and 0.8% for alcohol, tobacco and cannabis, respectively. Living in the less affluent area was associated with higher lifetime rates of tobacco and alcohol use. Substance use is less prevalent in Tanzania than in richer countries, but lifetime consumption is higher in poorer areas. The association of substance use with a range of socio-economic factors warrants further research.

Blood pressure and the global burden of disease 2000. Part 1: Estimates of blood pressure levels

OBJECTIVE

To provide global estimates of blood pressure by age and sex for adults aged > or = 30 years, by WHO subregion.

DESIGN AND METHODS

Data were obtained from studies identified in a literature review of population-based surveys. These were complemented by data from MONICA and INTERSALT studies. Estimates of the shape of the age-systolic blood pressure (SBP) association were made from survey data utilizing parametric and non-parametric analyses. A linear sex-specific association of SBP with age was demonstrated from 30 to 70 years in females and 20 to 70 years for males in each subregion. Mean age- and sex-specific estimates of SBP were estimated for each WHO subregion separately, based on study and country-weighted SBP data.

RESULTS

Analyses were based on data from about 230 surveys and over 660 000 participants. Age-specific mean SBP values ranged from 114 to 164 mmHg for females, and 117-153 mmHg for males. Females typically had lower SBP levels than males in the 30-44-year age groups, but in all subregions, SBP levels rose more steeply with age for females than males. Therefore, SBP levels in those aged > or = 60 years tended to be higher in females. Subregions with consistently high mean SBP levels included parts of eastern Europe and Africa. Mean SBP levels were lowest in south-east Asia and parts of the western Pacific.

CONCLUSIONS

These global estimates of blood pressure by age, sex and subregion show considerable variation in estimated levels. The lack of data in developing countries is substantial, and this is an important limitation given the role of blood pressure in increasing cardiovascular disease levels.

Trends in coronary artery disease and associated risk factors in sub-Saharan Africans

It has been suggested that the prevalence of coronary artery disease (CAD) is steadily increasing in sub-Saharan Africa. To address this issue, we conducted a Medline search of English language articles on cardiovascular diseases-and specifically CAD in Africa- from 1966 to 1997. The prevalence of CAD and related complications is relatively low in most regions in Africa compared to that obtained in the economically developed countries, although the situation is rapidly changing due to trends in urbanization, changes in lifestyle, acquisition of technology and the increasing numbers of tertiary care institutions. There are variations in reported prevalence rates within the different regions, but there is an upward trend in all the regions of the sub-Saharan Africa. This trend is believed to be related to the increasing frequencies of CAD risk factors in the subcontinent.

A Tanzanian perspective on the nutrition transition and its implications for health

OBJECTIVE

The purpose of this paper is to describe social and economic changes related to shifts in diet and activity and to present prevalences for chronic diseases associated with the nutrition transition.

DESIGN

Observations about social changes are descriptive, based on published reports and personal observations. Prevalence and trends data are based on a Ministry of Health published report and, for infants and toddlers, on primary data.

SETTING

Disease prevalences for diabetes mellitus and hypertension are taken from four sites, representing underdeveloped, semi-developed and well-developed rural communities and Dar es Salaam, the largest city in Tanzania. The prevalences of underweight and overweight for infants and toddlers are taken from a small periurban clinic in Tanzania.

SUBJECTS

Adults over 15 years of age are included in the prevalence data for chronic disease. The urban sample is stratified by occupation and ethnicity. The data for infants and toddlers include newborns to those aged 23 months.

RESULTS

An increase in the prevalence of diabetes and hypertension was observed. Simultaneously, there have been rapid changes in diet and physical activity related to urbanisation and modernisation. The highest prevalences for diabetes and hypertension were among high-ranking executives.

CONCLUSION

The increase in chronic disease could be related to the rise in the number of high-ranking executives. Simultaneously, per capita income has gone down, and malnutrition prevalence has risen. Programmes are being developed to simultaneously monitor trends in overweight while preventing protein-energy malnutrition and micronutrient deficiency.

Time travel with Oliver Twist--towards an explanation foa a paradoxically low mortality among recent immigrants

First-generation immigrant populations in industrialized countries frequently have a lower mortality than the host population, a finding that is unexpected and often dismissed as the result of bias. We propose an alternative explanation for a real, albeit temporal, mortality advantage. We base our argument on two premises: First, that there are differences in the progression of the health transition between the immigrants' countries of origin and industrialized host countries; and, second, that there are differences in the speed at which changes in mortality from various causes occur after migration. Mortality from treatable communicable and maternal conditions, still high in many countries of origin, quickly declines to levels close to those of the host country. Mortality from ischaemic heart disease, the most common cause of death in the host countries, takes years or decades to rise to comparable heights. This is because of the time lag between increases in risk factor levels and an increased risk of coronary death. Hence, first-generation immigrants may initially experience a lower mortality than the host population, a point that has so far been under-appreciated in discussions of immigrant mortality. After adopting a western lifestyle immigrants face an increasing risk of ischaemic heart disease. The increase occurs on top of a persisting risk from conditions associated with childhood deprivation, e.g. stomach cancer and stroke--the unfinished agenda of the health transition that immigrants experience.

Oral health behavior patterns among Tanzanian university students: a repeat cross-sectional survey

PURPOSE: This study examines oral health behavioral trends and the development of sociodemographic differences in oral health behaviors among Tanzanian students between 1999 and 2000. METHODS: The population targeted was students attending the Muhimbili University College of Health Sciences (MUCHS) at the University of Dar es Salaam (UDSM), Dar es Salaam, Tanzania. Cross-sectional surveys were conducted and a total of 635 and 981 students, respectively, completed questionnaires in 1999 and 2001. RESULTS: Cross-tabulation analyses revealed that in 1999, the rates of abstinence from tobacco use, and of soft drink consumption, regular dental checkups, and intake of chocolate/candy were 84%, 51%, 48%, and 12%, respectively, among students of urban origin and 83%, 29%, 37%, and 5% among their rural counterparts. The corresponding rates in 2001 were 87%, 56%, 50%, and 9% among urban students and 84%, 44%, 38%, and 4% among rural ones. Multiple logistic regression analyses controlling for sex, age, place of origin, educational level, year of survey, and their interaction terms revealed a significant increase in the rate of soft drink consumption, implementation of oral hygiene measures, and abstinence from tobacco use between 1999 and 2001. Social inequalities observed in 1999, with urban students being more likely than their rural counterparts to take soft drinks and go for regular dental checkups, had leveled off by 2001. CONCLUSION: This study provides initial evidence of oral health behavioral trends, that may be utilized in the planning of preventive programs among university students in Tanzania.

Worldwide distribution of blood lipids and lipoproteins in childhood and adolescence: a review study

Review and pooled analysis of the relevant worldwide literature was investigated from 1975 to 1996. Eighteen surveys out of 54 were suitable for analysis according to the selection criteria. This represents a total of 60494 observations from 26 countries all over the world. Data suggests differences as great as 76 mg/dl when comparing northern European countries to black African children. The overall curve of cholesterol with age observed in the pooled population indicates a pre-adolescent peak and then a slightly inverse change is observed for both boys and girls, from 3 to 12 years old being almost coincident absolute values. Beyond age 12, values for boys continue to slightly decrease to age 16, while for girls values tend to increase through this age-range. The curve in the late teens (16-18 years) tends to reach pre-teen levels for both sexes, although girls have consistently higher absolute values than boys. There is a great variation in the specific age-sex and race levels of cholesterol among different populations or even in the same populations over a period of time. However, an apparently universal pattern of an early rise, a fall, and a subsequent rise in mean values of total cholesterol by age from the preadolescence to late teens is observed. More data are needed on total cholesterol and lipid fractions between late school age and mid-adulthood.

Serum lipid and lipoprotein levels in Ghanaians with diabetes mellitus and hypertension

Both diabetes mellitus and hypertension alter lipid and lipoprotein metabolism and increase the risk of coronary artery disease. We have reported previously on lipid and lipoprotein levels in healthy Ghanaians, and this study deals with the levels of these biochemical parameters in Ghanaians with diabetes mellitus and hypertension. Fasting serum lipoproteins were determined on blood samples drawn from healthy male and female Ghanaians as well as age-matched individuals with either diabetes or hypertension. Cholesterol, high-density lipoprotein cholesterol (HDL-C), triglycerides, and fasting blood glucose were measured. Low-density lipoprotein cholesterol (LDL-C) and very low-density lipoprotein cholesterol (VLDL-C) were derived. Total serum cholesterol levels were 4.43 +/- 0.22 mmol/L and 4.67 +/- 0.26 mmol/L for diabetic males and females, respectively. High-density lipoprotein was 1.55 +/- 0.09 mmol/L and 1.50 +/- 0.09 mmol/L for male and female diabetics, respectively. Lipid and lipoprotein levels in the hypertensive patients did not differ from the above values. The levels of cholesterol and lipoprotein obtained in Ghanaians with hypertension and diabetes mellitus were similar to those of their age-matched healthy controls. These results suggest a reduced risk of coronary artery disease from the atherogenic effects of cholesterol in Ghanaians with diabetes mellitus and hypertension.

Serum lipid values in adolescents are related to family history, infant feeding, and physical growth

Total serum cholesterol (TC), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), triglycerides (TG), apolipoprotein A-I (apo A-I), apolipoprotein B (apo B), and lipoprotein (a) (Lp(a)) were analysed in 879 14- and 17-year-old healthy adolescents (477 boys and 402 girls), and related to family history of cardiovascular disease, early feeding, weight and length at birth, and physical growth during infancy and childhood. Mean TC was significantly higher in girls than in boys (4.4 and 4.2 mmol/l, respectively, both age-groups together). High TC values ( > 5.2 mmol/l) were more prevalent in girls than in boys: 14% and 17% compared to 6% and 12% in 14- and 17-year-old girls and boys, respectively. Mean TC and LDL-C values were lower during mid-puberty in both boys and girls while, in boys but not in girls, mean HDL-C values decreased and TG values increased successively with increasing pubertal stage. Girls who were taking oral contraceptives had higher mean values of TC (4.91/4.39 mmol/l), TG (1.32/0.83 mmol/l), and apo B (0.89/0.73 g/l). Boys with a family history of early deaths ( < 55 years) from myocardial infarction and girls with a family history of cerebral haemorrhage/thrombosis in fathers had higher mean values of TC (4.55/4.17 and 5.03/4.40 mmol/l, for boys and girls, respectively), LDL-C (2.84/2.47 and 3.08/2.56 mmol/l), and apo B (0.73/0.70 and 0.86/0.73 g/l). Adolescents with short duration of breast feeding ( < 6 months), or early introduction of infant formula, had higher mean values of TC (4.29/4.14 mmol/l) and apo B (0.72/0.68 g/l). There were no significant correlations between serum lipid values and body weight or length at birth, but adolescents with high LDL-C (upper quartile) seemed to have lower attained heights during infancy and childhood. In conclusion, this study shows that serum lipids in adolescence are primarily related to age and sex but also to early determinants like family history of cardiovascular diseases, infant feeding, and early physical growth.