Cultural and environmental influences on footedness: cross-sectional study in urban and semi-urban Malawi.

The present study was designed to assess cultural and environmental pressure against left-foot preference in urban and semi-urban Malawi. The findings demonstrated that, when compared to handedness, footedness appeared to be less biased behavioral laterality in culturally restrictive communities. The percentage of responders with negative views on left-foot preference was lower than that on left-hand preference (57% vs. 75%) and a smaller proportion of volunteers suggested that left-footers should be forced to change the foot (63.5% vs. 87.6%). In total, mobilizing and stabilizing tasks scored similar proportions of negative responses. Expectation of inferior performance of the left foot than the right one was the major reason for negative views on left-foot preference. Gender and driving experience had significant but weak effect on the view on left-foot preference. Most of the responders (74%) suggested that left-footers should change the foot in early family environment.

Spatial parameters of walking gait and footedness.

OBJECTIVE: The present study was undertaken to assess whether footedness has effects on selected spatial and angular parameters of able-bodied gait by evaluating footprints of young adults. SUBJECTS AND METHODS: A total of 112 males and 93 females were selected from among students and staff members of the University of Malawi using a simple random sampling method. Footedness of subjects was assessed by the Waterloo Footedness Questionnaire Revised. Gait at natural speed was recorded using the footprint method. The following spatial parameters of gait were derived from the inked footprint sequences of subjects: step and stride lengths, gait angle and base of gait. The anthropometric measurements taken were weight, height, leg and foot length, foot breadth, shoulder width, and hip and waist circumferences. RESULTS: The prevalence of right-, left- and mix-footedness in the whole sample of young Malawian adults was 81%, 8.3% and 10.7%, respectively. One-way analysis of variance did not reveal a statistically significant difference between footedness categories in the mean values of anthropometric measurements (p > 0.05 for all variables). Gender differences in step and stride length values were not statistically significant. Correction of these variables for stature did not change the trend. Males had significantly broader steps than females. Normalized values of base of gait had similar gender difference. The group means of step length and normalized step length of the right and left feet were similar, for males and females. There was a significant side difference in the gait angle in both gender groups of volunteers with higher mean values on the left side compared to the right one (t = 2.64, p < 0.05 for males, and t = 2.78, p < 0.05 for females). One-way analysis of variance did not demonstrate significant difference between footedness categories in the mean values of step length, gait angle, bilateral differences in step length and gait angle, stride length, gait base and normalized gait variables of male and female volunteers (p > 0.05 for all variables). CONCLUSIONS: The present study demonstrated that footedness does not affect spatial and angular parameters of walking gait.

Cultural and environmental pressure against left-hand preference in urban and semi-urban Malawi.

The study assessed views of teachers, pupils and their guardians on left-hand preference. Seventy-five percent of the responders indicated that the left hand should not be preferred for habitual activities and 87.6% of them indicated that left-handers should be forced to change the hand. Gender had significant effect on the view on left hand preference (df = 1, OR (odds ratio) = 0.465, p = 0.027). Giving a handshake when greeting a person, drawing and writing were the three top target activities against left-hand preference. An assumption that the left hand is less skilled and less powerful than the right one was the most common reason for negative view on left-hand use. Most of volunteers reported that parents and close relatives were the primary group of people who usually discourage left-hand use. Eighty point one percent of the responders indicated that people should stop preferring the left hand as soon as somebody noticed their left-handedness. The results indicated that cultural and environmental pressures might significantly affect visibility of left-handedness in urban Malawian populations.

Anthropometric indices in rural Malawians aged 45-75 years.

OBJECTIVE: The aim of this cross-sectional study was to assess anthropometric parameters of rural people aged 45-75 years in the Southern Region of Malawi. SUBJECTS: 97 males and 101 females aged 45-75 years were selected from 10 villages in Balaka district using a stratified cluster sampling method. Most responders were small-scale farmers growing maize and vegetables for household consumption. The anthropometric measurements taken were height, weight, triceps skinfold (TSK) and mid-upper arm circumference (MUAC). The derivatives from anthropometric measurements included body mass index (BMI), mid-upper arm muscle area (MUAMA) and mid-upper arm fat area (MUAFA). Weight status of Malawian subjects was estimated using WHO (1995) categories for BMI values, and height, weight, TSK, MUAC, MUAMA and MUAFA were compared with NHANES reference data for black sample. RESULTS: Correlation between age of subjects and the anthropometric indices was weak and insignificant. Males were generally taller and lighter than females. All anthropometric indices of Malawian subjects were considerably lower than NHANES medians. However the mean values of height, weight, MUAC and MUAMA of females were closer to the reference values than those of males. It was found that 9.1% of Malawian subjects had mild thinness (BMI 17.0-18.4 kg m(-2)), 13.6% had moderate thinness (BMI 16.0-16.9 kg m(-2)) and 18.2% exhibited severe thinness (BMI<16.0 kg m(-2)). The proportion of thin persons was higher (chi2 = 9.58, n = 1, p<0.01) among males than females (50.0% versus 35.7%). CONCLUSIONS: This study indicates that undernutrition is a serious problem among rural Malawians aged 45-75 years.

Anaemia in human African trypanosomiasis caused by Trypanosoma brucei rhodesiense.

OBJECTIVE: To find out if indeed anaemia is a major sign in human trypanosomiasis caused by Trypanosoma brucei rhodensiense. DESIGN: A one year cross-sectional study of all admitted and surveyed Trypanosoma brucei rhodensiense infected patients (June 2001-June 2002) SETTING: Nkhotakota District Hospital-Central Region of Malawi. RESULTS: After survey and investigations, 28 patients (16 males and 12 females) were admitted to Nkhotakota District Hospital with a parasite positive Trypanosoma brucei rhodensiense infection. Twenty four (85.7%) of them were anaemic. Their mean haemoglobin was 8.96 +/- 3.07 g/dl compared to controls that had a mean haemoglobin concentration of 12.17 +/- 1.35 g/dl (p < 0.000001, 95% CI -4.342 to -2.0785) (n = 45). None of the trypanosomiasis infected individuals had schistosomiasis or hookworms. Two patients had malaria. One of them was an 18-year-old pregnant woman with hepatosplenomegaly, who developed ante partum haemorrhage. She was jaundiced and had haemoglobin of 10 g/dl. She died after two weeks following the diagnosis and treatment. The other was a two-year-old girl who had haemoglobin of 8.4 g/dl. She also had hepatosplenomegaly. All the other patients looked well nourished with no other signs of chronic diseases. Hepatosplenomegaly was significantly related to the severity of illness (p = 0.011) but not to anaemia. CONCLUSION: Though basic, this study has shown that anaemia is indeed a complication of human Africa trypanosomiasis caused by Trypanosoma brucei rhodesiense. There is need for further investigation to investigate the type of anaemia that is caused by this disease.

Is handedness related to health status?

Handedness is the most important behavioural asymmetry due to its intimate association with the specialisation of the brain for language. It exists in 3 forms, namely right, left and mixed. Left-handers constitute the biggest minority group in the world and in many aspects they are in a disadvantaged position compared to right-handers. Numerous studies demonstrated association between left-handedness and different health problems ranging from learning disorders to breast cancer and decreased longevity. This paper reviews the relevant literature on the genesis of handedness and connection between handedness and health. Deviations from the "normal" pattern of braininess observed in some left-handers might contribute to developmental, cognitive and some mental disorders. However increased incidence of some of pathological conditions among sinistrals could hardly be explained by the "abnormal" pattern of braininess or by the action of a gene or genes responsible for handedness determination. Review of literature suggests that many of health problems of left-handers develop due to environmental, developmental and other mechanisms related to genesis of handedness.

Relationship between arm span and stature in Malawian adults.

OBJECTIVE: The aim of this cross-sectional study was to assess the relationship between height and arm span in adult Malawians. SUBJECTS AND METHODS: 142 males and 128 females between the ages 20 and 76 years were recruited from among the patients attending various clinics at Queen Elizabeth Central Hospital, Blantyre, Malawi. All subjects were free from physical deformities. The anthropometric measurements included standing height and arm span. RESULTS: The arm span exceeded height in all age groups of males and females. The mean difference between the height and arm span values for females was 9.9 +/- 4.9 cm (t = 16.28, p<0.001) and for males was 11.6 +/- 4.4 cm (t = 14.74, p<0.001). The gender difference between height and arm span measurements was statistically significant (t = 9.58, p<0.001 and t = 10.24, p<0.001, respectively). Correlation of arm span and height for males was 0.871 and for females was 0.815. Prediction equations were derived from regression analysis. RSD values were 8.709 and 6.914 for equations for males and females, respectively. CONCLUSIONS: Stature of Malawian adults can be estimated from arm span measurements using regression equations.

Leprosy in Nkhotakota District Hospital.

OBJECTIVE: To study the profile of leprosy cases at Nkhotakota District Hospital in Central Region of Malawi. DESIGN: Retrospective cross-sectional study of all registered cases of leprosy from records over a nine year period (January 1992 to April 2001) SETTING: Nkhotakota District Hospital-Central Region of Malawi. RESULTS: In total 526 cases of leprosy were identified from the records. The prevalence rates gradually increased from 0.998 per 10,000 cases in 1992 to 3.39 cases per 10,000 in 1995. There was however a gradual decline of prevalence rates from 1997/1998 that had 3.17 cases per 10,000 to 1.3 cases per 10,000 in 2001. 1996 registered 2.34 cases per 10,000. Fifty seven cases (10.8%) were found with children of the age of 14 or below and 469 (89.2%) cases were of adults. Paucibacillary leprosy presented with more cases than multibacillary leprosy (p < 0.0000001). There were 80 (15.2%) cases of multibacillary leprosy compared to 446 (84.8%) cases of paucibacillary leprosy. In addition more males were affected by multibacillary leprosy than females (p < 0.0001) and females were more affected by paucibacillary leprosy (p < 0.01) than males. CONCLUSION: The results show that paucibacillary leprosy though minor in Malawi can become endemic as paucibacillary leprosy is a reflection of leprosy contacts in the population. We therefore recommend continued epidemiological surveys of leprosy. Training in leprosy detection should be encouraged so that this disease can be totally eradicated in Malawi.

Quantitative analysis of gait pattern in hemiparetic patients.

OBJECTIVE: To characterise gait pattern in hemiparetic patients quantitatively using clinical footprint method. DESIGN: A case control study. SUBJECTS: Sixteen hemiparetic patients (12 males and 4 females) aged 16 to 64 years who attended neurological clinic at Queen Elizabeth Central Hospital, Blantyre, Malawi. MAIN OUTCOME MEASURES: Stride length, step width, foot rotation angle measured using footprint method. RESULTS: The difference in mean values of the three variables of gait between affected and unaffected sides in hemiparetic patients was not significant. However, strides were significantly longer in controls than in patients (P<0.001) while patients had significantly broader steps (P<0.02). In the controls, foot was rotated externally in 87.7% of steps and internally in 14.3% of steps. In the hemiparetic patients, intoeing pattern was observed in 41.3% of steps. The difference in variability of stride length and foot angle between affected and non-affected sides of patients was not significant. Stride-to-stride variability in stride length in patients was 1.6 times higher than in controls. Variability of step width and foot progression angle was 1.4 and 1.6 times higher in patients than in controls. CONCLUSION: Footprint method provides fast and inexpensive tool for clinical gait analysis and is suitable for evaluation of hemiparetic patients. Our findings suggest that areas of emphasis for physical therapy of hemiparetic patients should include increasing stride length and decreasing step width and internal rotation of foot, particularly on the affected side.

Growth of urban school children in Malawi.

The objective of this cross-sectional study was to assess growth pattern of urban school children in Malawi from low socio-economic strata and to compare anthropometric measurements of the children to data from the region of South-Central Africa and to international standards. A total of 493 urban school children aged 6-17 years were selected randomly from two primary schools in semi-urban Blantyre, the largest city in Malawi. Anthropometric measurements included height, weight, mid-upper arm circumference, triceps skinfold thickness, mid-upper arm muscle circumference and maximal grip strength of the stronger hand. All parameters of Malawian children of both sexes were lower than medians of WHO/NCHS reference data. Expressed as percentage of WHO/NCHS references, the relative means of height, weight, mid-upper arm circumference and mid-upper arm muscle circumference of Malawian girls were considerably higher than those of boys, and older girls had better parameters than younger ones. Older pupils of both sexes had higher triceps skinfold thickness relative to the international references than the younger children. Mean maximal grip strength values of boys and girls were not significantly different. For girls, the relative values increased with age, while for boys they decreased. It is concluded that younger primary school pupils have similar body sizes to their counterparts from the region. Adolescents, particularly girls, have more favourable anthropometric parameters which approach WHO/NCHS reference data.

Ventilatory capacity indices in Malawian children.

OBJECTIVE: To compare ventilatory capacity indices in healthy Malawian school children with those of other ethnic Africans and Caucasians. DESIGN: Forced vital capacity (FVC), forced expiratory volume in one second (FEV1), peak expiratory flow rate (PEFR), FEV1 expressed as a percentage of FVC (FEV%), weight and height. SETTING: Two primary schools in urban Blantyre, Malawi. SUBJECTS: Five hundred and fourteen apparently healthy school children (230 boys and 284 girls) aged six to 17 years. RESULTS: Ventilatory capacity indices (FEV1, FVC and PEFR) strongly and significantly correlated to body size and age of children of both sexes. The mean value of FEV% was 88.3% and it did not change significantly with increasing body size and age of children. The mean values of FEV1 and FVC were 9.8% and 10.8% higher in boys than in girls, respectively. The 1.4% gender difference in PEFR values was statistically non-significant. For FEV1 and FVC values, the average differences between Malawian and European children were between 20.5% and 23% while for PEFR the ethnic difference was about 12%. The Malawian children have similar ventilatory capacity indices to those of Nigerian, Jamaican and Tanzanian children. CONCLUSION: Prediction equations calculated in this study should be used for interpretation of ventilatory capacity indices in Malawian children instead of reference values for Caucasians or ethnic scaling factors. Computation of regional reference values for ventilatory capacity indices shall be continued. It shall embrace additional factors contributing to variance in respiratory functions such as customary physical activity, local environmental conditions, altitude of residence, nutritional status and smoking.

Left-handedness as a risk factor for head injuries.

OBJECTIVE: To study prevalence of left-handedness among traumatic patients with head injuries. DESIGN: A case-control study. SETTING: Queen Elizabeth Central Hospital, Blantyre, Malawi. SUBJECTS: One hundred and sixty three traumatic patients newly admitted to a surgical ward at Queen Elizabeth Central Hospital, Blantyre during one month period with exception of patients with arm injury, severe injury and confused patients. MAIN OUTCOME MEASURES: Maximal grip strength of both hands, questionnaire on hand preferred for eight habitual activities. RESULTS: The overall prevalence of left-handers determined on the basis of bilateral asymmetry in maximal grip strength was non-significantly higher in traumatic than in the control group. Relative to the control group, lefties were over-represented among victims of head injury, while prevalence of left-handers among patients with leg and trunk injuries and among controls was similar. Left-handed patients were more likely to sustain head traumas during fighting, road transport accidents and sport activities. Possible reasons for increased level of traumatisation among sinistrals are discussed. CONCLUSION: Left-handedness is a risk factor for head injuries obtained during confrontational activities. Therefore, left handers should avoid such type of behaviour in order to reduce traumatisation rate.

Prediction of peak expiratory flow rates in stunted children.

OBJECTIVE: To assess the effect of stunting on peak expiratory flow rates (PEFR) in Malawian children. DESIGN: Cross sectional study. SETTING: Two public primary schools randomly selected in Blantyre, the largest city in Malawi. SUBJECTS: 266 boys and 273 girls aged six to 14 years. MAIN OUTCOME MEASURES: PEFR, height, weight and age of children were determined using standard techniques. Nutritional status of children was assessed using WHO/NCHS height for age, weight for age and weight for height reference standards. RESULTS: The data of PEFR were analysed by regression on age and stature. One hundred children (18.6%) were classified as stunted. None of them was under weight or wasted. The equations for prediction of PEFR were calculated separately for stunted and non-stunted children. Stature was a significant predictor of PEFR values in both groups of children. The differences between stunted and non-stunted children of both sexes in slopes and intercepts of the regression lines of PEFR on stature were non-significant. Stunted children of both sexes had significantly lower PEFR than their counterparts with normal height for age index. CONCLUSIONS: Stunting in Malawian children aged six to 14 years is associated with decreased rate of development of PEFR in proportion to linear growth retardation. Prediction equations calculated for children with normal height for age index can be used for assessment of PEFR in stunted children.

Lateral asymmetry in grip strength: utility of the ten per cent rule.

OBJECTIVE: To measure asymmetry in grip strength between hands in left, right and mixed handers and to test utility of the ten per cent rule. DESIGN: A cross sectional study. SETTING: Queen Elizabeth Central Hospital, Blantyre, Malawi. SUBJECTS: One hundred and seventy six healthy volunteers (102 males and 74 females) aged 15 to 66 years were selected from visitors to the patients admitted at the hospital. MAIN OUTCOME MEASURES: Bilateral measurements of maximal grip strength, assessment of handedness using a questionnaire incorporating questions on hand preferred for six habitual activities. RESULTS: In about 70% of males and females, the right hand was stronger than the left hand while frequency of left, mixed, and right handers was 5.7%, 4.5% and 89.2%, respectively. Significant association (chi2 = 6.43, n = 2, p<0.05) was found between handedness and stronger hand with preferred hand being stronger in most subjects. However, for about 40% of left and mixed handers and 27% of right handers, the non-preferred hand was stronger. The mean differences between grip strengths varied between 10% and 20% in different categories of handers when stronger hand was taken into consideration. Without considering the stronger hand, the mean bilateral difference in maximal grip strength in the three categories of handedness was between three and six per cent.. CONCLUSION: Distinction between stronger hand and hand preferred for skilled activities should be made and considered when assessing limitations in hand strength in clinical practice.

Some physiological and psychophysiological signs of neuroticism level in healthy persons.

OBJECTIVE: To study cardiac reactivity on presentation of cardiotropic drug odour, perception of this odour and autonomic nervous system activity in high personality neuroticism healthy women. DESIGN: Cross sectional. SUBJECTS: 28 healthy female undergraduate university student volunteers in the age range 21 to 29 years. MAIN OUTCOME MEASURES: Eysenck Personality Questionnaire, threshold of nicethamidum odour detection, statistical parameters of electrocardiographic R-R intervals variance, Strain Index of cardiac regulatory systems (as a measure of the balance between sympathetic and parasympathetic system activities). RESULTS: Six subjects with low neuroticism level (LNL) and eight persons with high neuroticism level (HNL) were selected out of 28 young women volunteers using the Eysenck Personality Questionnaire. Baseline cardiac rhythm of the HNL group had a high level of stability and high values of the Strain Index which are characteristic of increased activity of the sympathetic nervous system. Increased variability of the cardiac rhythm and low values of Strain Index indicated elevated parasympathetic nervous system activity in LNL persons. HNL subjects also had low cardiac reactivity on presentation of nicethamidum solutions and high detection thresholds of odour stimuli. CONCLUSIONS: High neuroticism level in healthy females affects the balance between sympathetic and parasympathetic nervous system activities, cardiac reactivity on presentation of nicethamidum odour as well as perception of this odour. Low cardiac responsiveness to stimulatory effect of cardiotropic drug and increased sympathetic nervous system activity should be taken into consideration when planning treatment of neurotic subjects.

[Effect of diuretics on the activity of the blood kallikrein-kinin system in experimental inflammation]. / Vliianie diuretikov na aktivnost' kallikrein-kininovoi sistemy krovi v usloviiakh éksperimental'nogo vospaleniia.

Experimental inflammatory edema induced by subplantar administration of dextran was shown to activate the blood kallikrein-kinin system in rats. Furosemide, dichlothiazide and ethacyrnic acid (50 mg/kg) prevented this effect. Ethacrynic acid exerted the most pronounced action.