Obesity Indices and Peripheral Artery Disease Measured by Ankle Brachial Index in Nigerian Out-Patients.

BACKGROUND: Peripheral artery disease (PAD), an important component of the cardiovascular triad, has been linked with obesity as one of the risk factors for its development. The risk posed by obesity however varies depending on the indices measured. METHODS: We compared the relationship of measures of central and visceral obesity (waist circumference (WC) and waist-hip ratio (WHR) versus that of general obesity (body mass index (BMI) in the development of PAD among Nigerians with hypertension and/or diabetes mellitus. PAD was diagnosed when Ankle Brachial Index (ABI) was <0.9 in either limb. RESULTS: A total of 541 patients (194 males and 347 females) were studied with a mean age of 58.4(±0.46)years. The mean BMI, WC and WHR were 27.8 (±0.222)kg/m2, 96.8 (±0.515)cm and 0.941 (±0.003) respectively. Although the mean BMI, WC and WHR were higher in patients with PAD than those without PAD, the difference was only statistically significant for WC and WHR (p=0.003 and p=0.016) but not BMI (p=0.151). However, the difference in mean BMI was statistically significant in patients <60 years (p=0.015) but not in those >60 years (p=0.953). CONCLUSION: This study has shown that in Nigerian Africans measures of central and visceral obesity were more related to the development of PAD than BMI which is a measure of general obesity and that this lack of significance is probably due to the fact that PAD occurred more in older people as there was a significant relationship with PAD in people younger than 60 years old.

Lower extremity peripheral artery disease: prevalence and risk factors among adult Nigerians with diabetes mellitus.

BACKGROUND: Diabetes mellitus is an important risk factor for development of atherosclerosis. Lower extremity peripheral artery disease (LEAD) which is mainly due to atherosclerosis has been associated with not only increased risk of lower limb amputation but also increased risk of morbidity and mortality from major cardiovascular events such as stroke and myocardial infarction. Information on the prevalence of peripheral vascular disease is scanty in Nigeria. OBJECTIVE: The aim of this study was to determine the prevalence of LEAD and risk factors associated with its development in adult Nigerians with type 2 diabetes mellitus. METHODS: The study was cross-sectional. Patients were consecutively enrolled in the study between August 2009 and May 2010 from the Consultant out-patient department, University of Benin Teaching Hospital, Benin-City, Nigeria. LEAD was assessed in all the patients using Ankle Brachial Index <0.9 in either leg. The Edinburgh Claudication Questionnaire was used to determine if patient had symptomatic disease or not. RESULTS: Three hundred and eighty eight diabetic patients were enrolled in the study out of which 244 (62.9%) were females. The study showed that the prevalence of LEAD was 35.6% when diagnosed using Doppler ABI <0.9 in either leg. The ratio of symptomatic to asymptomatic disease was 1: 7.6. Advancing age, duration of diabetes and concomitant hypertension were important risk factors significantly associated with the disease. CONCLUSION: LEAD is not uncommon among type 2 diabetes patients in Nigeria and the majority were asymptomatic. Advancing age, duration of diabetes and concomitant hypertension were important risk factors identified.

Determination of lower extremity peripheral artery disease: the role for automated Oscillometric measurement of ankle brachial index in Nigerians.

AIMS AND OBJECTIVES: To determine the prevalence of LEAD and compare the accuracy of ABI obtained by automated oscillometric method with Doppler ultrasonography. PATIENTS AND METHODS: This study compared the accuracy of ABI obtained by automated oscillometric method versus that by Doppler among 153 hypertensive patients aged 18 years and above, attending the hypertension clinic of the University of Benin Teaching Hospital, Benin-City. RESULTS: Of the 153 patients studied, 64 (41.8%) and 48 (31.4%) had ABI <0.9 using hand held Doppler ultrasound and automated oscillometric method respectively, while 39 (25.5%) had LEAD detected by both methods. Assuming the gold standard for diagnosis of LEAD was by Doppler ABI < 0.9, ABI obtained by automated oscillometric method had a sensitivity, specificity, positive and negative likelihood ratios of 60.9%, 89.9%, 6.03 and 0.43 respectively while the area under the receiver operating characteristic curve was 0.787. There was good and positive correlation between ABI obtained by automated oscillometric method and Doppler ultrasound with a Pearson's correlation coefficient of 0.73 and 0.74 for left and right lower limbs respectively (p<0.001) CONCLUSION: ABI obtained using automated oscillometric method is a good alternative to Doppler ultrasonography when screening for LEAD.

The electrical axis of the heart in nigerian patients with chronic obstructive lung disease in Benin City.

BACKGROUND: Of the electrocardiographic changes in chronic obstructive lung disease (COLD) patients, a shift of the P wave axis greater than 900 which is highly characteristic, is said to be due to hyperinflation and does not occur in interstitial lung disease. OBJECTIVE: To describe the electrocardiographic changes in chronic obstructive lung disease patients. METHODS: The electrical axis of the various waves of the ECG using the hexiaxial reference system in 92 Nigerian patients with COLD were examined, 39 of whom had associated cor pulmonale. P wave axis greater than 900 was present in 2(19.1%) of 17 patients with COLD alone and 15(41.7%) out of 36 with development of corpulmonale (p<0.001). The mean P wave axis was 64.7 ± 10.6 0 in those without cor pulmonale while it was significantly shifted to the right (83.90) in those with cor pulmonale. The mean QRS axis was 53.50 ± 21.20 and 89.0 ±12.40 in those without and with cor pulmonale respectively (p=0.7716). The QRS axis was normal in all but one of those without cor pulmonale while there was a right axis deviation in 51.7% of those with it. ST and T wave changes were mainly present in those with associated cor pulmonale. CONCLUSION: The study shows that a shift of the electrical axis of the heart occurs in COLD patients mainly with the development of right ventricular hypertrophy (cor pulmonale), rather than the hyperinflation.

Sodium-lithium countertransport activity in normotensive offspring of hypertensive black Africans.

OBJECTIVE: To assess sodium-lithium countertransport (SLC) activity and erythrocyte sodium (ENa) levels in black (Nigerian) hypertensive (HT) patients, normotensive (NT) offspring of hypertensive parents and normotensive offspring of normotensive parents, and to determine if increased SLC activity is related to a familial predisposition to hypertension in black subjects as in Caucasians. METHOD: The study was done using 60 Nigerian subjects of Edo ethnic origin in three groups of 20 each: (a) untreated new HT patients at the University Teaching Hospital, Benin City; (b) NT children of hypertensive parents (NTHT) traced home and matched for age, sex and body mass index (BMI) with (c) NT children of NT parents (NTNT). SLC activity was measured using a modified method of Canessa et al 1980 and ENa assessed by flame photometry. RESULTS: SLC was markedly higher in both HT patients and NTHT subjects than the NTNT subjects. The values were 0.351+/-0.011 vs 0.199+/-0.014 mmol Li/rbc (P < 0.0001) and 0.347+/-0.020 vs 0.199+/-0.014 mmol Li/rbc/hr (P < 0.0001), respectively. The values were not different between the HT and the NTHT group (P > 0.05). ENa was higher in the HT group than both NT groups which were similar. Values were 10.55+/-0.46 (HT) vs 7.78+/-0.62 (NTHT) (P < 0.0001) and 10.55+/-0.46 (HT) vs 8.62+/-0.47 mmol/L (P < 0.0001). There were no correlations between either SLC activity or ENa and any of the other measured variables such as age or BMT. CONCLUSIONS: SLC activity was elevated in normotensive children of hypertensive subjects to a similar degree as hypertensive patients and in a pattern reminiscent of that seen in Caucasians. SLC activity may thus be associated with a familial predisposition to hypertension in black subjects as in their Caucasian counterparts.

Relationship of the ECG with ventilatory function tests in chronic obstructive lung disease (COLD) in Nigerians.

Although the most objective assessment of the severity of COLD is done by spirometer, this is not as readily available in Nigeria as the electrocardiograph, thus the ECG is often used to assess it. This study examines the relationship between the ECG findings and FEV 1 obtained by spirometry and expressed as a proportion predicted for age and sex in 92 Nigerians with COLD of which 39 had associated pulmonate. There was an inverse relationship between the mean electrical axis of the P wave on the ECG and the FEV 1 of predicted. The axis was more positive (82 +/- 12 degrees) among those with FEV 1 less than 50% of predicted (group 1) and this decreased progressively with increasing FEV 1 to 72 +/- 14 degrees in those with FEV 1 between 50-70% (group 2) and 67 +/- 16 degrees in those with FEV 1 greater than 70% (group 3). There was also a significant relationship between FEV 1 and the development of cor pulmonale and 71.4% of those who had the lowest FEV 1 (group 1) had cor pulmonale while the proportion decreased with the reduction in the severity of airway obstruction. A rightward P wave axis greater than 80% was statistically significant associated with development of cor pulmonale (X2 = 29.5 (P < 0.001) of those with COLD and cor pulmonale, 72.2% had a P wave axis greater than 80%. Only 13.2% of those with COLD alone had a P wave axis greater than 80 degrees. Cardiac arrhythmias were present in 28 patients, ventricular (VA) in 23 cases, and atrial (AA) in 7 cases. Both AA and VA were associated with more severe airway obstruction. All 3 patients who had atrial fibrillation (AF) and FEV 1 below 50% of predicted (group 1) and had cor pulmonale while 2 of the remaining 4 with AA also were in group 1 and the remaining 2 in group 2. The distribution of ventricular arrhythmias (VA) showed that 10 (43.5%) were in group 1, 9 (39.1%) in group 2, and 2 (8.7%) in group 3. Both VA and AA were also significantly related to the development of cor pulmonale. A P wave amplitude greater than 2.5 mm was significantly related to the development of clinical cor pulmonale X2 = 24.6 P < 0.001. The results show that ECG findings correlate well with spirometric assessments of FEV 1 and clinical severity in Nigerians with COLD and are, therefore, useful where spirometry is unavailable.

How common is heart failure due to systemic hypertension alone in hospitalised Nigerians?

Hypertension is regarded as the most common cause of heart failure in Nigeria and other Black African countries. A few reports suggest that heart failure due to hypertension hardly occurs without the presence of an extra burden on the heart from the presence of other cardiac risk factors. This study assesses the occurrence of other potential causes of heart failure in 55 consecutive admitted cases of hypertensive heart failure. All but six cases (88%) were associated with the presence of one or other significant cardiac risk factors while 56.2% were associated with multiple heart failure risk factors. Five of the six were poor drug compliers. Of the six, only one was completely free of cardiac risk factors and he was unaware of his hypertension and so had never had therapy. The others either consumed alcohol moderately, had mild renal impairment or were grossly obese. The factors found were anaemia, renal dysfunction, abnormal glucose tolerance, alcoholic ingestion and co-existing valvular heart disease. The finding shows that among Nigerian patients hospitalised for hypertensive heart failure, heart failure was rare in those hypertensive patients who had no extra cardiac burden, and therefore control of these factors will help prevent the development of heart failure in hypertension with its dismal prognosis.

Heart failure in Nigerian hypertensive patients: the role of renal dysfunction.

Heart failure in hypertensive patients is known to be dependent not only on the absolute value of blood pressure but also on other factors, hence the prognosis varies. In this study, the effect of renal dysfunction on the development of heart failure in hypertensive patients was assessed. Fifty-five patients who were admitted in hypertensive heart failure (HHF) were compared with 55 hypertensive patients who had never been in heart failure (HT), in their renal function, assessed by serum creatinine and urea levels. The haemoglobin (Hb) and serum albumin (Alb) levels were also measured. The two groups were matched for age, sex, level of blood pressure and body mass index. The duration of hypertension was similar in both groups. Mean serum creatinine was higher in the HHF group: 4.50 +/- 0.90 vs. 0.97 +/- 0.06 mg/100ml (P < 0.001). Also the Hb and Alb levels were lower in the HHF than the HT group: 11.63 +/- 0.40 vs. 13.2 +/- 0.21 g/100 ml (P < 0.001) and 3.7 +/- 0.1 vs. 4.40 +/- 0.09 g/100 ml (P < 0.001), respectively. The proportion with abnormal renal function (creatinine > 1.5 mg%) was also significantly higher in HHF: 28/55 vs. 8/54, chi 2 = 16.3 (P < 0.001). When adjustment was made for low serum albumin, Hb and fundal changes by multivariate analysis, serum creatinine was significantly higher in the HHF group: F = 4.294 (P < 0.05). Low serum albumin was also independent of haemoglobin and creatinine: F = 19.52 (P < 0.001), but Hb was not significantly different after adjustment for Alb and creatinine. This study suggests that renal dysfunction is independently associated with the development of heart failure in HT patients.

Prosthetic valve dysfunction and the law: a case presentation from Nigeria.

The possible legal implications of the failure of a mechanical prosthetic cardiac valve have been reviewed within the framework of the Nigerian legal system. This is the sequel to a clinical case we had recently, of primary mechanical failure of a cardiac prosthesis which led to the death of a 19-year-old medical student. A short account of the case as reported by the physicians is presented. As there has been no such case before any Nigerian Court, this review draws heavily upon salutary lessons from the USA and the UK, where such, or related, cases are more prevalent.

Prosthetic valve dysfunction in a Nigerian.

A case is presented of a mechanical cardiac valve dysfunction occurring in a 19-year-old Nigerian 7 years after valve surgery and presenting with cardiac failure, supraventricular tachycardia and later, cardiogenic shock but initially masquerading as generalised bleeding probably from Warfarin-drug interaction. The problem of management of an artificial heart valve in our setting is discussed.

Multiple lentigines syndrome in a Nigerian family.

Three cases of the multiple lentigines syndrome are reported in a Nigerian family, involving a father and two of his children. The major abnormalities in this syndrome include: multiple lentigines, cardiac defects, genitourinary malformations, neurological deficits, growth retardation, cephalofacial dysmorphism and a family history consistent with an autosomal dominant mode of inheritance. We hereby report these cases in whom the main features are multiple lentigines, ocular hypertelorism, electrocardiographic defects and a pattern consistent with an autosomal dominant mode of inheritance.

Serum lipid and apolipoprotein levels in a Nigerian population sample.

Serum lipids and apoproteins have been measured in 307 men and 235 women living around Benin City in Nigeria. Total serum cholesterol values are low compared both to White Western populations and to American Blacks. HDL-cholesterol levels, however, are comparable to values in Western and Oriental men, but lower than in Western women. A highly significant correlation exists between total cholesterol and apo B and between HDL-cholesterol and apo A-I in men and women. The low serum lipid values are related to a low dietary fat intake, almost exclusively from palm oil, in the Nigerian population.