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Occasional Survey

THE PLIGHT OF MODERN BUSHMEN

STEPHEN J. D. O’KEEFE ROBYN LAVENDER

Nutrition Unit, Groote Schuur Hospital and University of CapeTown, South Africa; and Department of Dietetics, Red Cross

Memorial Childrens Hospital, Cape Town

Summary The nutritional status of 51 adult Bushmenin northeast Namibia, who have been

forced to abandon their traditional hunter/gatherer lifestyleand merge with pastural/urbanised Hereros of Bantu origin,was assessed. Controls were 23 local medical staff and

investigators. The diet was very unbalanced, consisting oflittle more than refined maize meal. Any money earned wasusually spent on alcoholic beverages which, at such times,replaced normal food intake. Although short stature is

thought to be genetic in origin (Bushmen were on average 15cm shorter than Hereros), body mass corrected for heightwas severely diminished in 30% of adults, fat stores weredepleted in 70%, and arm muscle was reduced in 75%. Ingeneral, women were more depleted than men. Blood testsshowed low plasma vitamin C, folic acid, and vitamin A andE concentrations compared with controls. Plasma proteinconcentrations suggested a high frequency of chronic liveror enteric diseases. Examination of 44 hospital patientsshowed that 85% had pulmonary tuberculosis, andnutritional depletion was universal. The results raise seriousdoubts about the survival of Bushmen as an independentethnic group.

INTRODUCTION

THE Bushmen are the original inhabitants of SouthernAfrica, having arrived about 10 000-25 000 years ago.About 2000-4000 years ago they were joined by theHottentots, a group with closely similar ancestors. However,the Bushmen continued to be hunter/gatherers whereas theHottentots were pasturalists, as were the black Bantu andwhite Europeans that arrived in more recent times.

Unfortunately, the Bushmen did not differentiate betweenwild animals and domestic cattle. Frequent cattle raidsresulted in heated conflict and the gradual extinction ofBushmen bands from the Cape in the early nineteenthcentury and from Natal at the end of that century. Theelimination from Natal was secured by a combined

operation between British, Boer, and Zulu forces. In 1848Charles Baker, editor of the Natal Guardian, said "Bushmenshould be totally eliminated so that the colonists could livewithout fear of their property being stolen ... ".Although they are few, Bushmen have survived by

seeking refuge in areas regarded as unfit for human

habitation, such as the Kalahari desert region of Botswanaand Namibia/South West Africa. Until lately they havelived successfully in harmony with the environment. AsVetter has stated, "Where no dweller of other peoples couldlive anymore the Bushmen feels at home, knows preciselyplaces where to find water, knows trees and shrubs he cangain food from, and always finds again the plains where thestarch-containing veld onion grows".1 However, modern

technology has now threatened his last stronghold. TheAfrican population explosion has increased the demand formore land. Wells have been sunk and the desert madeliveable for other people. Cattle and goats have beenintroduced at the expense of the wild-life on which thetraditional Bushman depends. Without controls this

practice can result in short-term benefits and long-termdisaster: overgrazing causes bush encroachment and loss ofpastural lands, and overuse of water causes a drop in thecritical water table. The end result is a disturbance in the

precarious balance of the semi-desert ecology, leading topermanent desert conditions incapable of supporting life.Few true hunter/gatherer Bushmen now survive. Most havebeen drawn into the surrounding Bantu and white farmlandareas where they are ill equipped to play a useful part, exceptas unskilled labour in return for food and water.An earlier study in Namibia drew our attention to the

severe nutritional problems of Bushmen in relation to localblack (Bantu) tribes such as Hereros and Kavangos, and thatthe problem was common to all areas where Bushmen livedclose to other black populations. We therefore selected onesuch area, the. Otjinene district of East Hereroland, toevaluate the dietary habits, nutritional status, and diseasepatterns of Kalahari Bushmen of the !Kung subgroup whohave abandoned their nomadic lifestyle and now live on thefringes of Herero farmlands and villages.

SUBJECTS AND METHODS

Most male Bushmen interviewed had no permanent occupationbut provided casual labour for the Hereros. Their dwellings,situated on the perimeter ofHerero settlements, consisted of flimsystructures constructed from branches and grass. All settlementsvisited contained many small children and most postpubertal girlswere either pregnant or breastfeeding, sometimes both (fig 1). Thesurvey was conducted with the assistance of the local district nurses.

Nutritional status, dietary intake, interview, and blood sampledata were obtained for 30 female and 21 male adults (aged 17 toabout 70 years), generally at the clinic that was used as a base. Thisinitial assessment was followed by visits to the individual dwellingsto examine living conditions and any other Bushmen who wereunable to attend the Clinic.To investigate the disease patterns in the population

anthropometric measurements and disease states of an additional 30women and 14 men were documented at the two small

multipurpose hospitals serving the area (Okakarara and Gobabis).

Fig 1—Family group of rural Bushmen.

Note difference in stature between author (height 1 78 m) and Bushmen.Despite the poor hvmg conditions, the large number of children seen is typicalof Bushmen settlements.

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Nutritional status was assessed from physical state,

anthropometric measurements, and blood tests Z3 Dietary intakewas estimated by the use of a standardised frequency questionnaire4and three-day recall. Anthropometrical measurements were

evaluated by comparsion with internationally accepted standards2,3or by use of the body-mass index (BMI, reference range: men 20-25kg/m2, women 19-24 kg/m2); body weight depletion was defined asa BMI of under 17, fat depletion as triceps skinfold thickness lessthan 60% of normal, and muscle depletion as mid-armcircumference less than 80% of normal.2,3

Haemoglobin concentration was measured locally in blood

samples collected in the field, duplicate samples being immediatelyfrozen and transported in liquid nitrogen to Cape Town forbiochemical tests. In addition, control samples were taken from 23local medical staff and members of the investigation team andprocessed in the same way. Plasma proteins were measured bynephelometry. Vitamin analysis included whole blood nicotinicacid,s thiamine/transketolose activity,6 red cell folate (Amershamradioassay), and plasma vitamin C, A, and E.7,8

RESULTS

Assessment of Nutritional Status

Not one overweight Bushman was seen. There was nofemale obesity and, if anything, women were thinner thanmen. Skin changes were characteristic of the elderly people;the face, hands, and arms being wrinkled and creased, andthe skin hypertrophic. Sun-exposed areas were in generalhyperpigmented with dry scaly skin. Oral hygiene wasuniformly poor. Most of the old were either partially ortotally edentulous, any remaining teeth being loose andsurrounded by pericoronitis. Gingivitis was also common inthe young. Corneal scarring with partial loss of vision wasseen in 3 elderly individuals.The table shows the anthropometric measurements in

Bushmen and previously reported values in Hereros.2Nutritional depletion, indicated by these measurements,was considerably more prevalent among Bushmen thanHereros, especially in women. Hospital patients were evenmore deficient in body fat, body mass, and muscle mass.Fig 2 shows haemoglobin and plasma protein values in 27 ofthe rural, healthy individuals (randomly selected). The

ANTHROPOMETRIC MEASUREMENTS (MEAN [SD]) IN BUSHMEN AND

HEREROS (BANTU)J f -

*See ref 2.

HB ALB FER IGG IGA IGM AAT TRange 0-20 0-50 0-600 0-50 0-10 0-5 0-10

g/L g/L fcg/L g/L g/L g/L g/L

Thiamine Nic acid Vit C Folate Vlt A Vrt ERange: 0-200 0-100 0-1 0-1,000 0-2,000 0-20

U/L p.moi/L mg/100 ml ng/ml tS/L mg/L

Fig 2-Individual haemoglobin and plasma protein values (upper)and plasma and whole blood vitamin concentrations (lower).

HB, haemoglobin; ALB, albumin; FER, ferritin: IGG, IGA, and IGM,immunoglobulins; AAT, alpha-1 antitrypsin concentration; nic acid, nicotinicacid; dots, patient values. Control range (mean, 2 SD) shown as vertical bars.

pattern was one of anaemia, hypoalbuminaemia, andhypergammaglobulinaemia. Blood vitamin concentrationssuggested deficiencies of vitamin C, folic acid, and vitaminsE and A in a large proportion of the sample, compared withthe medical staff/investigation team control samples.

Dietary Intake

The only food consistently eaten was refined maize meal.Because of the arid country, maize meal had to be

purchased. The flour is typically refined white maize mealwhich is mixed with water and cooked outside in cast iron

pots over wood fires. The resultant porridge ("pap") hasbecome synonymous in Bushman language with a meal.The porridge is usually flavoured with cane sugar, salt, or,occasionally, fat derived from milk or cooked beef barteredfrom Herero herdsmen. Meals such as these were usuallyeaten in communal gatherings between two and three timesa day.During the three day recall only 3 Bushmen had eaten

meat. 30% denied having eaten meat, the remainder

generally obtaining small quantities towards the end of themonth when they had money. Unlike Hereros, 50% ofBushmen denied ever having drunk fresh milk and 30%occasionally obtained sour milk. During the recall periodonly 20% had had a milk product in their diet. Althoughchickens were commonly observed around Hererosettlements, eggs were not a usual food source.

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None of the Bushmen had eaten vegetables or fruit duringthe recall period and 45 % claimed never to eat fruit. Duringthe rainy season (November to March) wild leafy vegetableswere used to flavour porridge, otherwise only onions,cabbage, and bananas were purchased by some at the end ofthe month. Traditional foods had not been collected fromthe land and hunting was not considered for the provision offood.Water was obtained from the communal well and, on

average, women consumed 250 ml of water and men 500 ml

daily. Locally brewed beer was regarded by most of the menas the perfect food: consequently, when it was available, itgenerally replaced the already inadequate diet. The beer isbrewed from a mixture of yeast and grain known asmtombo; it can also be purchased from Hereros at about 20cents (about 0.07) per 500 ml. Excessive consumptionoccurred particularly at weekends: 50 % of men interviewedon Monday had consumed between 2 and 4 litres per daywith little food, and many still had signs of intoxication at thetime of inteview. Beer consumption by women wasconsiderably less.

Nutrition and Disease

The skin and mucosal changes observed in the ruralpopulation were also seen in patients and, in addition, 5patients had signs of pellagra with Casal’s necklaces. 85 % ofBushmen in hospital had acute infections most of whichinvolved the respiratory tract. Tuberculosis accounted for82% of cases. It was noteworthy that although Bushmenform a minority of the local population (about 5%), thetuberculosis wards were predominantly occupied by them(75%). Concomitant infection of family members,especially mothers and infants, were common. By contrastin Hereros hypertension was common and tuberculosisoccurred only in 10%.2 No Bushmen had hypertension.Trauma, generally secondary to physical violence, was thenext most common reason for admission of Bushmen.

DISCUSSION

Our results show that the nutrition and health ofBushmen who have abandoned their traditional way of lifeare desperately poor. Even allowing for their geneticallydetermined short stature, body mass, fat, and protein storeswere grossly depleted. Although malnutrition is commonthroughout rural Africa, our results indicate that Bushmenare particularly at risk. Overall, nearly a third of subjectsstudied had significant (ie, between 20 and 40% lower thanthe lower limit of normal) depletions in body mass, 70% infat stores, and 75 % in muscle protein stores compared withrates of between 5% and 12%,20% and 40%, and less than5%, respectively, in rural black South Africans andNamibians of Bantu origin..2 The severe depletion inprotein and energy stores was associated with vitamin

deficiencies, particularly of vitamin C and folic acid. Ourdietary analysis showed that these deficiencies could bewholly attributed to the unbalanced diet. The intermittenthigh alcohol intake exacerbated the situation.The clinical manifestations of nutritional deficiencies are

difficult to identify in generally malnourished Africancommunities.9 The skin and mucosal changes seen inBushmen were possibly related to combined deficiencies ofprotein and vitamin C and A, whereas anaemia wasassociated with folate deficiency. Low plasma albumin

concentrations provide an index of chronic disease and,when combined with raised immunoglobulinconcentrations, are suggestive of chronic liver disease orchronic enteric infections. The increased ferritinconcentrations could also be a result of underlying liverdisease, or attributable to the association between dietaryiron overload, alcoholism, and siderosis in rural Africanswho cook and brew alcohol in cast iron pots. toThe predominance of infectious disease, especially

pulmonary tuberculosis, was unquestionably related to thehigh frequency of protein-calorie malnutrition and its effectson host defence. Many workers have identified the strongrelation between malnutrition and infection" and our

investigations in other African subgroups have shown aclose association between nutritional depletion andtuberculosis.2,3 The effect of malnutrition on cell-mediated

immunity as well as the high rate of transmission of diseasein over-crowded, unhygienic environments, such as those ofthe Bushmen, may account for the predominance oftuberculosis.The high frequency of malnutrition amongst female

Bushmen contrasts strongly with the situation seen in otherrural Africans where men are usually the most depleted ;2,3 inHereros 30% of women were obese.z Although we did notassess the nutritional status of children, many of theBushmen women interviewed in hospital had infants inhospital with severe marasmus or kwashiorkor complicatedby tuberculosis.The plight of the modern bushmen in Namibia is clearly

grave and the future bleak. Scattered groups of Bushmenstill exist in neighbouring Botswana and Angola, butaccording to Van der Post12 their situation is equally gloomy.The Bushman race is not likely to survive as an independentethnic group and will inevitably become absorbed into localblack communities. The loss of the Bushmen and hisdistinct and unique culture can only be a loss to Africa and tous all. We feel they now have little self-respect: they had noconsistent employment, the menfolk abused alcoholwhenever possible, and Bushmen were generally despisedand mistrusted by their black cohabitants. Ironically, one oftheir few successful deployments as trackers for the SouthAfrican Defence Force in the Angolan War is now also injeopardy with the imminent withdrawal of South Africantroops. Other attempts at development have been made bythe South West African/Namibian Government in the areadesignated Bushmanland. This move has had as littlesuccess as the homeland policies of South Africa since onlyabout 3% of the Bushmen population live within this area.We can only hope that once Namibia gains its independencethe critical condition of the Bushmen is not overlooked.

We thank Mrs Janice Ogden and Dr Gerry Young of the gastroenterologyclinic, and Prof Peter Jacobs and Dr John Graves of the Department ofHaematology, University of Cape Town, for help with the blood sampleanalyses; Mr Phillip Roberts, Mrs Elspeth Burke (gastroenterology clinic),and Sister Agnes Ward and her staff at the Otjinene clinic for help with thefield survey; and Dr Rodian Krause and the South West Africa Departmentof Health and Welfare for permission to perform the study.

Address for correspondence: J. D. O’K., Department of Gastroenterology,Mayo Clinic, 200 First Street Southwest, Rochester, MN 55905 USA.

REFERENCES

1. Vedder H. Das Alte Sudwestafrika. 5th Edition. Johannesburg- Thorold’s AfricanaBook, 1985.

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2. O’Keefe SJD, Rund JE, Marot NR, Symmonds KL, Berger GMB. Nutritionalstatus, dietary intake and disease patterns in rural Hereros, Kavangos and Bushmenin South West Africa, Namibia. S Afr Med J 1988; 73: 643-48.

3. O’Keefe SJD, Thusi D, Epstein S. The fat and the thin a survey of nutritional statusand disease patterns among unbanized black South Africans. S Afr Med J 1983; 63:679-83.

4. Ndaba N, O’Keefe SJD. The nutritional status of black adults m rural districts of Nataland Kwazulu. S Afr Med J 1985; 68: 588-90

5. Clark BR, Halpem RM, Smith RA. A fluorimetric method for quantitation in thepicomole range of N-methylnicotinamide and nicotinamide in serum. Anal.Biochem 1975; 68: 54-61

6. Brin M, Tai M, Ostashever AS, Kalinsky H. The effect of thiamine deficiency on theactivity of erthrocyte haemolysate transketolase. J Nutrition 1960; 71: 273-81.

7. McKormick DB. Vitamins. In: Tietz NW, ed. Textbook of clinical chemistryPhiladelphia: W. B. Saunders, 1986.

8. Labadanos D, O’Keefe SJD, Dicker J, et al. Plasma vitamin levels in patients onprolonged total parenteral nutrition. J Parent Ent Nutr 1988; 12: 205-11.

9. Davidson S, Passmore R, Brock JF, eds. Human nutrition and dietetics, part III. Vthed. Edinburgh: Churchill Livmgstone, 1972: 293-97.

10. Bothwell JH, Seftel H, Jacobs P, et al. Iron overload in Bantu subjects. Am J Clin Nutr1964; 14: 47-51.

11. Scrimshaw NS. Protein deficiency and infective disease In. Monroe HN, Allison JB,eds. Mammalian protein metabolism, vol 2. London: Academic Press, 1964.

12. Van der Post L, Taylor J. Testament to the Bushmen. Harmondsworth. PenguinBooks, 1985 100-20.

Hospital Practice

POSTURE AND CENTRAL VENOUSPRESSURE MEASUREMENT IN

CIRCULATORY VOLUME DEPLETION

PETER AMOROSO ROGER N. GREENWOOD

Academic Department of Anaesthetics, King’s College School ofMedicine and Dentistry, London; and Department of Nephrology,

The Lister Hospital, Stevenage

Summary The effect of posture on central venous

pressure (CVP) was studied in 16 patientswith circulatory volume depletion before and after fluidreplacement. At presentation, measurement of CVP whensupine did not reflect circulatory volume depletion, with amean (SEM) of 0·1 cm H2O (0·6), but when sat at 45° theCVP showed a striking fall in all patients to -9·7 cm H2O(1·1). After fluid replacement, the CVP was 2·3 cm H2O(0·4) when supine, and -0·4 cm H2O (0·4) at 45°. In theassessment of circulatory volume depletion, CVP should bemeasured with the patient sat at 45°, if possible:measurement of CVP in a supine patient may not detect orseverely underestimate circulatory volume depletion.

INTRODUCTION

MEASUREMENT of central venous pressure (CVP),usually by insertion of a cannula into the superior vena cavavia the internal jugular vein, is often used to assess

circulating blood volume in patients thought to be fluiddepleted. When the technique is taught to medical studentsand junior hospital doctors emphasis is usually, and

correctly, placed upon insertion of the cannula when thepatient is positioned head-down, aseptic technique,connection of the 3-way tap and manometer, and choice of asuitable anatomical point to which the height of the columnof blood supported by right atrial pressure can be referred byuse of a spirit level. However, the effect on CVP of thepatient’s posture is largely ignored. This omission is

surprising because measurement of a fall in systemic bloodpressure, associated with a rise in heart rate when the patientrises from a supine to a sitting or standing position, is

regarded as an essential part of the examination of a patientwith suspected circulatory volume depletion. This clinicalobservation is held to be an appropriate response to areduced left ventricular filling pressure brought about bygravitational pooling of an inadequate blood volume-butthe right ventricular filling pressure should be similarly

affected by posture. When CVP is measured to assessvolume depletion, the effects of posture should therefore beemphasised.

SUBJECTS AND METHODS

For this prospective study, a patient was considered to haveclinical evidence of circulatory volume depletion if systolic bloodpressure fell by more than 15 mm Hg, in association with a rise inheart rate of more than 5 beats/min, when raised from a supineposition to a sitting position in which both legs were horizontal withthe torso at an angle of approximately 450. Patients with oedema orwith visible distension of the jugular veins when sitting, in any partof the respiratory cycle, were excluded. Measurements were madebefore and after correction of circulatory volume depletion for eachpatient.

16 patients met the criteria for circulatory volume depletion atpresentation (8 men, 8 women; mean age 58 years, range 37-72). 5patients had peritonitis as a complication of continuous ambulatoryperitoneal dialysis (CAPD), 3 of whom had fluid depletion becauseof vomiting, paralytic ileus, or both conditions, and 2 as a result ofexcess ultrafiltration during rapid exchanges of dialysis fluid: nonehad clinical or bacteriological evidence of septicaemia. 4 patientshad chronic renal failure with an acute exacerbation because of

inadequate fluid intake and diuretic therapy in 2, and inadequatefluid intake with salt-losing nephropathy in 2. 2 patients becamevolume-depleted during renal transplant rejection, and anotherpatient had acute tubular necrosis because of inadequate fluidreplacement after abdominal surgery. 1 patient had pre-renal failureafter self-poisoning with salicylate 2 days before admission, and 1patient had pneumonia with fluid depletion. No patient was ontreatment for hypertension. After correction of volume depletion, 8patients with chronic renal disease were mildly hypertensive, 1 ofwhom subsequently required hypotensive treatment. Patients werenot tested for evidence of autonomic dysfunction, but none haddiabetes mellitus.