Prevalence of obesity and overweight in urban adult Nigerians.

Obesity is increasingly a major health problem in parts of the developing world. It has reached epidemic proportions among Africans living in the Western Hemisphere; similar potential may exist in urban Africa. We explored this possibility in an urban setting in Nigeria, Africa's most populous nation. A screening survey was carried out among randomly selected 998 civil servants, 581 men and 417 women, in Ibadan, a major Nigerian city. Biographical data were collected using standardized questionnaires, and measurements of anthropometric indices, blood pressures and plasma glucose concentration. Obesity and overweight were defined by body mass index based on international criteria. Prevalence of obesity was 8.82% (confidence interval [CI]=7.13%, 10.75%), overweight 17.45% (CI=15.12%, 19.95%), and overweight plus obesity=26.18% (CI=23.47%, 29.03%). Prevalence of obesity among the women was 17.27% (CI=13.76%, 21.24%) and for men 2.75% (CI=1.58%, 4.43%). Among the women 42% were obese or overweight compared with 15% of the male population. Obesity and overweight were associated with higher socioeconomic status. Prevalence of obesity and overweight in the study population is comparable to rates seen in many industrialized countries, and rapidly emerging urbanized populations in Africa.

Relationship between height, glucose intolerance, and hypertension in an urban African black adult population: a case for the "thrifty phenotype" hypothesis?

An association between the factors of low birth weight and fetal growth retardation and subsequent risk of cardiovascular disease has been proposed; this is the basis of the "thrifty phenotype" hypothesis described in relation to type 2 diabetes mellitus. The relationship between height, presumably an indicator of early life experience, and glucose intolerance and hypertension was examined in a sample survey of noncommunicable disease in an urban African adult population. Height, other anthropometric measurements, and biosocial data were obtained in the study of 998 civil servants selected by multistage sampling in Ibadan, a major Nigerian city. Ibadan is a low-prevalence region for diabetes, with a rate of 0.8% and 2.2% for an impaired glucose tolerance. The prevalence rate of hypertension was 10.3% in the population. A significant negative correlation was found between height and blood glucose level (r = -0.14, p < 0.001), whereas there was no correlation with blood pressures. Multiple regression analyses did not demonstrate height as a determinant of either blood pressure or plasma glucose. However, in a logistic model height was found to be associated with abnormal glucose tolerance (diabetes and impaired glucose tolerance) (odds ratio, 0.01; p < 0.003). In the logistic model of the blood pressure data there was no association between height and hypertension. There was some association between height and blood glucose level and also glucose intolerance in the urban African population sample, but none with elevated blood pressure. The significance of the observed inverse relationship, though uncertain, deserves further exploration.

Hypertension in a black population: prevalence and biosocial determinants of high blood pressure in a group of urban Nigerians.

AIMS: To define the prevalence of hypertension, a major cause of morbidity and mortality in blacks, and related biosocial factors in an urban African population group. METHODS: The setting was that of a civil service population in Ibadan, a major city in Southwestern Nigeria. Nine hundred and ninety-eight civil servants selected by multistage sampling participated in the survey. Biosocial data including smoking history, alcohol use and level of physical activity; anthropometry, blood pressure and plasma glucose measurements were obtained. Diagnosis of hypertension was based on blood pressure of > or =160/95 mm Hg or known hypertensive on treatment. RESULTS: The overall prevalence rate of hypertension was 10.3% (CI, 8.4%, 12.2%), rates of 13.9% and 5.3% were obtained in men and women respectively in spite of a much higher rate of generalised obesity in the latter. Hypertension was associated with higher salary grade level, but there was no relationship found with regular exercise, smoking and alcohol. Obesity (body mass index (BMI) > or =30 kg/m2) was associated with hypertension only in women. A two-sided t-test demonstrated age, waist circumference, waist to hip ratio (WHR) and plasma glucose level as significant variables. In multivariate ANOVA models of systolic blood pressures, age, male sex and BMI were highly significant factors (P < 0.0001) and plasma glucose was also significant (P < 0.016); the same variables (except plasma glucose) were associated with diastolic blood pressures. In logistic regression models the variables which predicted hypertension were WHR, plasma glucose, age, sex and family history of diabetes. CONCLUSIONS: Prevalence of hypertension in the study was comparable to recently reported rates in urban Nigeria and similar populations in Africa. The biosocial determinants of hypertension in the urban black population were age, male gender, higher socio-economic status, BMI, plasma glucose, generalised and central adiposity. Regional fat distribution was a stronger predictor of hypertension than generalised obesity in the population.

Prevalence of diabetes and impaired glucose tolerance in Nigerians, Jamaicans and US blacks.

The prevalence of type 2 diabetes, impaired glucose tolerance and associated risk factors were compared in sample surveys in Africa and the Caribbean with the Third National Health and Nutrition Survey (NHANES-III) from the United States. A total of 856 Nigerians, 1286 Jamaicans, and 1827 US blacks were included in the study. Body mass index (BMI) increased in a stepwise fashion across the three populations groups, ie, 23 kg/m2 in Nigerians, 26 kg/m2 in Jamaicans, and 28 kg/m2 in US blacks. The corresponding age-adjusted prevalences of type 2 diabetes among persons aged 25-74, were 1%, 12%, 13%. Jamaican women were found to have the same prevalence of type 2 diabetes as US women (14 vs 13%, respectively); mean BMI was likewise very similar (28 kg/m2 in Jamaican and 29 kg/m2 in US women). BMI and waist-to-hip ratio were both associated with type 2 diabetes prevalence. Findings of this study confirm the marked gradient in type 2 diabetes risk among these genetically related populations and suggest that the blacks in the island nations of the Caribbean and the United States are at particularly high risk. Nigerians exhibited remarkably well-preserved glucose tolerance. Understanding the factors that limit the risk of type 2 diabetes in West Africa, beyond relative absence of obesity, would have considerable public health significance.

Prevalence of diabetes mellitus and impaired glucose tolerance in a group of urban adults in Nigeria.

This survey was undertaken to determine the prevalence of diabetes mellitus and impaired glucose tolerance in a group of urban adults in Ibadan, Nigeria. A total of 998 subjects randomly selected from five main ministries and departments in the Government Secretariat participated in the survey. Each subject was asked to fast overnight and ingested 75 g of glucose dissolved in 250 mL of water after answering a questionnaire. Relevant anthropometric measurements such as weight, height, waist and hip diameters, and blood pressure also were taken. After 2 hours, of blood was drawn and plasma glucose concentration measured. Diagnosis of diabetes or impaired glucose tolerance was based on 1985 World Health Organization (WHO) cut-off values. Blood glucose results were available in 875 subjects. Seven subjects were found to be diabetic for a prevalence of 0.8%, with the majority (5 subjects) being newly diagnosed. Nineteen were found to have impaired glucose tolerance for a prevalence of 2.2%. There were no sex differences between the two groups. All of the newly diagnosed diabetics were asymptomatic. Multivariate analysis revealed that subjects with a family history of diabetes, higher body mass index, and higher systolic blood pressure had higher blood glucose levels. The prevalence of diabetes in this survey is lower than rates reported in recent surveys in Nigeria that used less stringent criteria and different methodologies. The rate is comparable to that of a Tanzanian study that used WHO criteria. However, the rate of impaired glucose tolerance in this study, first to be reported in Nigeria, is lower than that obtained in the Bantu population.

Health problems and socio-demographic findings in elderly Nigerians.

Nine hundred and fifty-one persons aged 60 years and over, living at home in four locations in southwestern Nigeria were studied. The cohort representing urban and rural dwellers, constituted 7.8% of the total population. Female residents had higher widowhood rates and lower levels of educational attainment than males. Multigenerational living arrangements were popular. Ninety-five percent of the cohort had no physical impairment on assessment of activities of daily life. Only 6.4% were on a regular pension (males more than females, P < 0.001) and income for 75% was less than the estimated poverty line (females more than males P < 0.001). Estimated crude death rate was also higher than the national average. The effects of these socio-demographic factors on health are diverse. Comparisons were made with similar studies in other cultures.

Attitude to aging among different groups in Nigeria.

Attitude to aging and the aged was surveyed in three groups of Nigerians, 1) caregivers living at home with the elderly, 2) various categories of hospital workers, and 3) the general public. Based on scores of an eleven-item questionnaire the best attitude was in caregivers, and the poorest in hospital workers. Years of education had an overall negative effect on attitudinal measurement. An inference from this study is that the elderly are still valued, but caregivers could be under some stress and would appreciate assistance. It is important for developing countries like Nigeria to begin to think seriously of what types of public assistance the elderly and their families would need.

The pattern of medical illness in a community of elderly Nigerians.

A community survey of Nigerians aged 60 years and above was carried out. Nine hundred and fifty one subjects were interviewed by trained nurses. Seven hundred and fifty nine (79pc) had physical examination carried out on them. It was found that musculoskeletal, dental, ocular and cardiovascular disorders were the commonest problems in this group of people. Poor dental hygiene, anaemia and goitre were problems significantly associated with living in rural areas, while hypertension was commoner in urban areas, but this did not reach significance at five pc level. The results show that about one out of five elderly Nigerians suffer from chronic disabling conditions such as osteoarthritis and 2.4pc of them were diabetic. The impact of these chronic diseases on the health of the elderly Nigerians is discussed and suggestions made for health promotion interventions and treatment programmes.

A prospective study of insulin-dependent diabetic Nigerian Africans.

Newly diagnosed insulin-dependent diabetic Nigerian Africans were studied prospectively over a 6-year period and were analyzed for sex, age at diagnosis, and month of onset of symptoms. Insulin-dependent diabetes mellitus (IDDM) rarely occurred in patients younger than the age of 10. A female preponderance occurred in those aged 20 and younger, and a male preponderance occurred in those aged 20 and older. The onset of symptoms occurred predominantly in the dry months of the year (October to March), peaking in February. The educational level and current employment status of the patients were compared with age- and sex-matched controls. The diabetics were found to have significantly less education, and approximately one third (34.9%) were unemployed compared with 10% of the controls. Control of the disease was found to be poor in three fourths of the patients. Various factors that prevent young diabetics in developing countries from living a full life are discussed.

Sheehan's syndrome in a developing country, Nigeria: a rare disease or problem of diagnosis?

Over a five year period, 11 cases of Sheehan's syndrome were seen in the Endocrinology Unit of a teaching hospital in Ibadan, Nigeria. The mean age at diagnosis was 35.1 years; the mean parity was four and the average interval between the obstetric injury and diagnosis was 6.9 years. Four patients were in middle socio-economic class and seven were in low socio-economic class. The most frequent presenting symptoms were failure of lactation (11 out of 11 patients) and amenorrhoea (9 out of 11 patients). Seven patients had multiple endocrine insufficiency involving essentially all pituitary cell types. Six out of 8 patients were lost to follow-up. In a review of autopsy records over a 5-year period at the same institution, out of 1,951 post-mortem examinations, no additional cases of Sheehan's were found. With an average of about two clinical cases per year, it would seem that Sheehan's syndrome is still a relatively rare entity in this part of the world in spite of the poor level of obstetric care generally available. There is a need for increased awareness about this disease on the part of practitioners in developing countries in order to establish whether this rarity is real or it is due to missed diagnosis.

Respiratory function in insulin-dependent diabetic patients

The study was designed to evaluate the difference in some respiratory functions between insulin-dependent diabetic patients(n=19) and non-diabetic individuals (n = 19). The measured values of FVC; FEV1 and PEFR of the diabetic patients were compared with those of the non-diabetics; as well as the predicted volumes for Nigerians. The diabetic patients showed significantly lower values when compared with the non-diabetics and the predicted volumes. The reduced volumes observed were related to the widespread abnormality of connective tissue known to occur in diabetes. The need for studies on larger population of insulin-dependent patients was highlighted

Insulin--binding antibodies in Nigerian diabetic patients.

The levels of insulin antibodies were determined in 68 diabetic patients on insulin treatment and 30 normal subjects. Fifty (73.5%) of the patients had low levels of insulin antibodies (less than 20%), twelve (17.7%) had moderate levels (between 20 and 40%) while the remaining six (8.8%) had high antibody levels (greater than 40%). There was poor correlation of insulin antibody level with insulin dose (r = 0.16, p less than 0.1) and with duration of disease (r = 0.19, p less than 0.5). Where high levels of antibodies were detected the problems encountered in treating the patients with highly purified insulin preparations are discussed.

Acromegaly in Ibadan--a report of six cases.

Six patients with acromegaly were seen over a six year period at the University College Hospital, Ibadan, Nigeria. There were 5 males and 1 female giving a sex ratio which differed from the equal sex prevalence observed in larger caucasian series. The diagnosis was made strictly on clinical grounds with corroborative evidence from x-ray of the skull and limbs. An unusual and unexpected finding was the observation of a hernia or a history of herniorrhaphy in 4 out of the 5 male acromegalics. It was not certain whether the association was real or what the explanation might be. Transfrontal surgery was the only definitive form of treatment that could be offered to the patients because of lack of facilities for transphenoidal adenomectomy or pituitary irradiation. The operation was refused by 4 of the 5 patients to whom surgery was recommended because of cultural fears regarding operations on the brain. Bromocryptine was prescribed as an alternative therapy but its scarcity and prohibitive cost precluded any serious compliance. There is a need to highlight the problems of the silent sufferer of endocrine disorders in developing countries.

Thyrotoxicosis in Nigeria. Analysis of a five year experience.

Fourty cases of thyrotoxicosis seen over a 5-year period in the endocrinology service of a teaching hospital in Ibadan, Nigeria have been reviewed. The clinical manifestations are not different in any way from the pattern described in other parts of the world and there was a female preponderance in a ratio of 4:1. The ratio of diffuse toxic goiter to toxic multinodular goiter was only 3:2, underscoring the relative uncommonness of Grave's disease, an autoimmune disorder, in Nigerian Africans. The study also demonstrated an increase in the hospital prevalence of thyrotoxicosis in Ibadan in the last 10-15 years; however, the incidence rate of 8 cases per year is still low when compared to experiences in other parts of the world. The presence of a goiter, ocular changes, high sleeping pulse rate, fine silky-smooth skin and thin, short and scanty hair have been identified as important clinical clues to look for to aid in the diagnosis of a difficult case in an environment where there are no facilities for thyroid function tests. Surgery was the most dependable form of treatment because of the cost and scarcity of drugs and complete absence of radiotherapy.

Insulin secretory reserve in diabetic Nigerian Africans.

The insulin secretory capacity of three groups of Nigerian African diabetics was assessed by measuring the concentration of C-peptide before and after stimulation with oral glucose. Group 1 subjects had a history of keto-acidosis and were treated with insulin. Those in group 2 had no history of keto-acidosis but required insulin to normalize blood glucose while those in group 3 also had no history of keto-acidosis and were treated with diet alone or in combination with oral hypoglycaemic drugs. C-peptide levels (mean +/- s.e.m.) showed group 1 subjects to be insulin deficient (fasting 0.08 +/- 0.04 pmol/ml, peak 0.14 +/- 0.03 pmol/ml), group 2 to have reduced insulin secretion (fasting 0.16 +/- 0.01 pmol/ml, peak 0.35 +/- 0.01 pmol/ml) and group 3 to have a moderately reduced fasting insulin and a higher peak insulin secretion (fasting 0.27 +/- 0.03 pmol/ml, peak 1.49 +/- 0.4 pmol/ml) compared with a non-diabetic control group (fasting 0.30 +/- 0.03 pmol/ml, peak 1.16 +/- 0.1 pmol/ml). Although the aetiology of diabetes in the Nigerian African is unclear, a spectrum of the disease exists which is similar to that in Caucasian population.

Cheiroarthropathy and long term diabetic complications in Nigerians.

Two hundred and fifty six consecutively ambulant diabetic patients attending a Nigerian diabetic clinic for the presence of cheiroarthropathy were examined using standard criteria. Forty eight (19%) had limited joint mobility of the hand, a prevalence higher than the 4% (2/56) observed in a non-diabetic population matched for age and sex. Limited joint mobility was twice as prevalent in the insulin treated (16/50, 32%) than in the non-insulin dependent (32/206, 16%) diabetics. Indices such as age, duration of diabetes, and glycaemic control (as assessed by integrated blood glucose concentration over the previous 12 months and glycated haemoglobin (HbA1c concentrations) were the same in the diabetics with and without limited joint mobility. The prevalence of cataracts (18/48, 38%) and background retinopathy (8/48, 17%) was higher in diabetics with limited joint mobility than in those without (respectively 6-9% and 5-6%); hypertension, peripheral neuropathy, and foot ulcers, however, were about equally common in the two groups of diabetics (with and without limited joint mobility). Nephropathy appeared commoner in diabetic subjects without limited joint mobility. Our results confirm previous observations in Caucasians of an increased prevalence of limited joint mobility in diabetes, especially those receiving insulin treatment, and also showed that limited joint mobility could predict the presence of retinopathy and cataracts in those diabetics. Neuropathy and hypertension were not commoner in our diabetics with limited joint mobility (unlike in the Caucasian population), suggesting that racial factors may underlie the predictive value of limited joint mobility in diabetic microangiopathy.

HLA-DR associations in black type I diabetics in Nigeria. Further support for models of inheritance.

The distributions of HLA-A, -B, -(Bw4/Bw6), -C, -DR, -(DRw52/DRw53), and -DQ genes in 19 type I diabetics, 37 type II diabetics, and 13 nondiabetics of the Yoruba tribe in southwestern Nigeria were studied. Because no associations between type II diabetes and HLA were detected in the current study and such associations are not known to exist in most ethnoracial groups, type II diabetics plus nondiabetics were used as a group of controls for the group of type I diabetics. Trends toward associations between increased DR3 (53 versus 30% of controls) and decreased DR2 (21 versus 46% of controls) and type I diabetes were found (0.1 greater than P greater than 0.05). The strongest HLA association with type I diabetes in Caucasians is usually with DR4. The percent of DR4-positive type I diabetes (11%) was not significantly greater that that in the controls (4%). Because the strong HLA associations with type I diabetes in American Blacks are the same as in Caucasians (i.e., increased DR3 and DR4 and decreased DR2), the genetic contribution (i.e., the lack of an association with DR4) to susceptibility to type I diabetes in most Nigerian Blacks may be different from that in most Caucasians and American Blacks. Onset of diabetes in most of the type I subjects was after age 20, and type I diabetics were difficult to recruit for the study, in keeping with reports on the rarity of type I diabetes among Blacks in western Africa and reports of DR4, but not DR3, being correlated with an early age of onset in Caucasians.(ABSTRACT TRUNCATED AT 250 WORDS)

Haemoglobin A1 levels in Nigerian diabetic patients using microcolumn affinity chromatography.

Haemoglobin A1 (HbA1) levels were measured in forty-five diabetic Nigerians and thirteen non-diabetic controls using disposable microcolumn kits based on affinity chromatography. The effect on HbA1 results of storage of whole blood samples for 1 week at room temperature and in a refrigerator was also evaluated. The mean +/- s.d. of HbA1 levels in diabetic patients and controls were 12.1 +/- 5.6% and 5.2 +/- 0.90% respectively. The difference was highly significant, P less than 0.001. Newly diagnosed diabetic patients who had not been on any treatment had significantly higher mean value of HbA1, 14.4 +/- 5.0%, than old patients already on treatment, 9.5 +/- 2.9%, P less than 0.01. In a group of nine patients, the mean +/- s.d. of baseline HbA1 value was 10.3 +/- 4.2% and after 1 week storage of different portions of the samples at room temperature and in a refrigerator, the mean +/- s.d. respectively were 9.8 +/- 3.6% and 11.0 +/- 4.2%. There was thus a slight decrease on storage at room temperature and a slight increase during refrigeration but the observed differences were not statistically significant. It is concluded that the glyc-affinity micro-column chromatography is a satisfactory and potentially useful method for measuring HbA1 levels in tropical developing countries. The method was easy to use and the assays could be run under average ambient room temperature without recourse to use of an air-conditioned room or a special chromatography chamber.

Reproductive performance following active management of diabetic pregnancies at the University College Hospital, Ibadan, Nigeria.

This article presents a report of the first 5 years of an active approach to the management of diabetic pregnancies at the University College Hospital, Ibadan. During this period the incidence rate of diabetic pregnancy was 0.64 per 1000 deliveries per year. The mean birthweight (3.40 +/- 1.68 kg) of babies whose mothers had good diabetic control was lower than the mean birthweight (4.19 +/- 1.05 kg) of babies born to mothers with poorly-controlled diabetes. The difference was however not statistically significant (P less than 0.5). Whilst the overall perinatal mortality rate was 10.8%, there was a statistically significant difference in the perinatal mortality associated with poor control of diabetes (42.9%) when compared with good control (0.0%): P less than 0.02. The authors conclude that earlier booking in pregnancy, stricter control of diabetes by multiple insulin injections and improved cooperation of the patients will in future help to lower the perinatal mortality rate associated with diabetic pregnancy.