Maternal work and childhood nutritional status among the Purari,Papua New Guinea

In traditional economies, body size, physical work capacity, subsistence productivity, and nutrition of adults may be interrelated, and one cross‐generational effect of these relationships may operate through the household, influencing nutritional status of children. In this analysis, the relationships among adult body size, work productivity in terms of time spent making sago starch, dietary diversity, nutrient availability, and childhood nutritional status are examined in the Purari population of Papua New Guinea, a group largely dependent on the starchy staple palm sago, which is devoid of all nutrients apart from energy. Observations of work scheduling, household food and nutrient availability, and nutritional status were carried out for 16 women, their households, and their children. A multiple regression model of hours spent in sago making on a particular day with days spent in other subsistence activities showed a negative relationship with the number of days spent in sago‐making and a positive relationship with the number of days spent fishing. The number of hours spent in sago‐making on a particular day was also positively related to daily per capita availability of protein at the household level. This is not a function of maternal nutritional status, however, since there is no association between body size of adult females and the number of hours spent making sago on a particular day. Nor does the greater per capita protein availability at the household level in households where women spend longer on a particular day in sago‐making result in improved childhood nutritional status. Since relationships among adult body size, work productivity, dietary diversity, nutrient availability, and childhood nutritional status are only partially demonstrated in this population, it may be that these linkages may only be important if physically arduous work is needed more consistently than is the case in the Purari delta. Am. J. Hum. Biol. 15:472–478, 2003. © 2003 Wiley‐Liss, Inc.     

Socio-economic factors associated with physique of adults of the Purari delta of the Gulf Province,Papua New Guinea

OBJECTIVE: To examine in detail the relationships between components of the modernization process, including experience of urban life, urban connectedness, education, and the nature and diversity of income sources on adult body size in a Papua New Guinea (PNG) population. METHODS: Mean height, weight and body mass index (BMI) of 292 adults surveyed in 1995-97 in the Purari delta, PNG, are reported by age group, and related to modernization variables including urban life, urban connectedness, economic status and education. RESULTS: With respect to BMI, 23% of males and 24% of females had a BMI greater than 25, while 1% of males and 6% of females had a BMI greater than 30. There were also significant numbers of undernourished individuals, especially among the females, where 13% had BMI below 18.5, compared with 5% of males with BMI below this level. Mean stature of younger adults is greater than that of older adults. For the males, height, weight and BMI are all negatively associated with age-squared, and positively associated with income. Weight is also positively associated with having urban relatives, but not with having lived in any urban centre. For the females, height is positively associated with age-squared, weight is positively associated with both income and number of years of education, while BMI is positively associated with income, and with having urban relatives, but not with urban dwelling per se. CONCLUSIONS: The secular trend toward increasing height may have been underway since the 1950s. Income level, number of years of education and having urban relatives emerge as core factors influencing body size and fatness in the Purari population.     

Village distance from urban centre as the prime modernization variable in differences in blood pressure and body mass index of adults of the Purari delta of the Gulf Province, Papua New Guinea

OBJECTIVE: The study examined the extent to which the geographical proximity of villages to an urban centre and other modernization variables are associated with variation in blood pressure and body mass index (BMI) of adults of the Purari delta of the Gulf Province, Papua New Guinea (PNG). METHODS: Mean BMI, systolic blood pressure (SBP) and diastolic blood pressure (DBP) of 292 adults surveyed in 1995-1997 in the Purari delta, PNG, are reported by village of residence, and related to modernization variables, including village of residence, urban life, urban connectedness, economic status and education. RESULTS: Mean BMI, SBP and DBP differ according to village of residence, there being a gradient in mean blood pressure from highest in the village closest to the urban centre, Baimuru, and lowest in the village most distant from it. The gradients in these variables across the three villages are not due to differences in age structures between the villages. Place of residence, which represents the distance from town, has the greatest impact on the BMI of males, while among the females, the number of relatives living in urban centres had a significant effect on BMI. For both males and females, place of residence has the strongest effect on SBP. While for the males, place of residence is the only significant factor associated with SBP, for the females, SBP is also associated with BMI, level of income and to a lesser extent with age. Very similar results were obtained for DBP. CONCLUSIONS: Distance to urban centre appears to have a strong effect, relative to other modernization variables, on BMI and blood pressure, this effect being far stronger for males than for females. In large part, this effect operates by way of differences in number of sources of income as well as number of close relatives of women who are resident in an urban centre. Reasons for the male-female differences observed may include gender differences in degree of mobility, and possibly greater physical sensitivity of males to the environment than females. Traditionally, there have been clear divisions of labour between males and females, the latter spending longer in subsistence activities than the former. It is speculated that males have more free time to travel to town should they wish, while women may travel to town to take produce to market, and be limited by how much time they spend in town when they are there, by the need to return to carry out household and subsistence tasks. It may also be that young adult males are more susceptible to modernization, in that they exhibit a greater degree of non-conformity than young women, and may be more favourably disposed to adopt aspects of western lifestyle.     

Acetylator phenotypes in Papua New Guinea

Acetylator phenotypes have been determined in 139 unrelated subjects from the hitherto untested populations of Papua New Guinea, and their relevance to current antituberculous isoniazid chemotherapy is discussed.     

Fertility and infertility in Papua New Guinea

Fertility levels in selected populations of coastal and highland Madang Province of Papua New Guinea are analyzed from reproductive history data. Changing levels of fertility between 1964 and 1984 are examined using reconstructed censuses. Age-specific infertility rates are calculated and evaluated with available data on rates of sexually transmitted diseases (STD) and contraceptive usage. These suggest that STD-associated infertility may be a major factor underlying levels of fertility lower than expected. © 1993 Wiley-Liss, Inc.     

Energy expenditure,physical exertion and time allocation among Hulispeaking people in the Papua New Guinea Highlands

Objectives: The study aimed to (1) elucidate the energetic adaptations of Huli people by comparing the three sub-populations in relation to their diversified natural and socioeconomic environment, based on energy expenditure and time allocation data; and (2) assess the applicability of a new index of physical exertion levels of activities (physical exertion index: PEI). Research design and methods: Married males and females (n = 43) were selected, including 14 from a hilly village, 13 from a flat swampy village and 16 migrants to a town. Continuous heart rate (HR) monitoring, in conjunction with minute-by-minute observation of activities, was undertaken. Total energy expenditure was assessed by flex-HR method and physical activity level (PAL) was calculated as multiples of basal metabolic rate. Observed activities were divided into 15 categories and the PEI was calculated for each: PEI= (mean HR of a categorized activity)/(flex HR) x 100. Results : No significant difference was found in PAL among the three sub-populations: 1.77, 1.92 and 1.81 for men and 1.78, 1.98 and 1.66 for women in hilly and flat villages, and a town, respectively. The comparison of the two village groups revealed that hilly terrain did not affect substantially the physical intensity of agricultural activities. On the other hand, the town migrants were engaged in sedentary paid jobs and these were less energy consuming than agricultural work. However, the different energy costs between paid jobs and agricultural work were offset by longer work time in the town group than in the two village groups (251 vs 50 or 70 min in males; 258 vs 152 or 138 min in females), resulting in similar PAL in the three groups. Conclusions: Despite contrasting natural and social environments, no significant difference was found in daily physical activity level among the three sub-populations (two villages and a town) of Huli-speaking people in Papua New Guinea Highlands.     

Energy expenditure, physical exertion and time allocation among Huli-speaking people in the Papua New Guinea Highlands

OBJECTIVES: The study aimed to (1) elucidate the energetic adaptations of Huli people by comparing the three sub-populations in relation to their diversified natural and socioeconomic environment, based on energy expenditure and time allocation data; and (2) assess the applicability of a new index of physical exertion levels of activities (physical exertion index: PEI). RESEARCH DESIGN and METHODS: Married males and females (n = 43) were selected, including 14 from a hilly village, 13 from a flat swampy village and 16 migrants to a town. Continuous heart rate (HR) monitoring, in conjunction with minute-by-minute observation of activities, was undertaken. Total energy expenditure was assessed by flex-HR method and physical activity level (PAL) was calculated as multiples of basal metabolic rate. Observed activities were divided into 15 categories and the PEI was calculated for each: PEI = (mean HR of a categorized activity)/(flex HR) x 100. RESULTS: No significant difference was found in PAL among the three sub-populations: 1.77, 1.92 and 1.81 for men and 1.78, 1.98 and 1.66 for women in hilly and flat villages, and a town, respectively. The comparison of the two village groups revealed that hilly terrain did not affect substantially the physical intensity of agricultural activities. On the other hand, the town migrants were engaged in sedentary paid jobs and these were less energy consuming than agricultural work. However, the different energy costs between paid jobs and agricultural work were offset by longer work time in the town group than in the two village groups (251 vs 50 or 70 min in males; 258 vs 152 or 138 min in females), resulting in similar PAL in the three groups. CONCLUSIONS: Despite contrasting natural and social environments, no significant difference was found in daily physical activity level among the three sub-populations (two villages and a town) of Huli-speaking people in Papua New Guinea Highlands.     

Associations between anthropometric variables and reproductive performance in a Papua New Guinea highland population

Associations between anthropometric variation and reproductive performance have important ecological and evolutionary implications. Bivariate associations between measures of reproductive performance (live births and offspring still living at the time of interview) and 24 anthropometric variables were examined in 150 females, aged 21–44 years, from the Eastern Highlands district of Papua New Guinea. Where significant linear or curvilinear associations with age existed, the reproductive and anthropometric variables were age-corrected. Linear, quadratic and cubic regressions were computed for each bivariate regression of age-corrected reproductive variable on age-corrected anthropometric trait. Positive linear regressions were found in the cases of body weight, triceps skinfold and head breadth. Positive cubic regressions were found in the cases of upper arm circumference, calf circumference, bicondylar femur and wrist breadth. It is suggested that these associations may reflect important ecological factors which influence both anthropometric and reproductive variation. U-shaped associations were found in the cases of wrist breadth and bicondylar femur. Inverted U-shaped associations were found for stature, sitting height, bizygomatic diameter and morphological face height. These curvilinear associations may be interpreted in terms of natural selection, and suggest that stature and sitting height may be undergoing stabilizing selection in this population.     

Parotid gland enlargement and female reproductive performance in a Papua New Guinea highland population

Swelling of the parotid salivary glands is commonly observed among males and females of highland Papua New Guinea. Evidence suggests that the condition is related to the highlanders' high starch consumption in the form of sweet potato. In this paper we regard parotid enlargement as an indicator of high energy intake and test its association with two measures of reproductive performance, the number of live births and living offspring, in a sample of 274 women from Lufa in the Eastern Highlands District of Papua New Guinea. Multiple regression analysis including maternal age showed that parotid enlargement is postively correlated with both measures of reproductive performance. Given that parotid gland enlargement in this population is due to persistent starch consumption, and that the condition represents above average energy intake, these results suggest that increases in energy intake relate to increases in reproductive performance in this sample of highland females.     

Size relationships among permanent mandibular molars in Aboriginal Australians and Papua New Guinea Highlanders.

Size relationships among crown units of permanent mandibular molars were investigated in two Sahul-Pacific samples: Aboriginal Australians (Yuendumu) and Papua New Guinea Highlanders (Wabag). Measurements of first, second, and third molars (M1, M2, and M3), including overall mesiodistal and buccolingual diameters as well as the mesiodistal and buccolingual diameters of the trigonid and talonid, were obtained from dental casts using a sliding caliper. Molar reduction was noted in talonid dimensions within both samples, but the trigonid mesiodistal diameter was not reduced in M2 or M3 compared with M1, indicating that the later-developing crown unit (talonid) was more reduced than the early-developing unit (trigonid). M2 was most reduced in size mesiodistally of the three molars, but its buccolingual diameter was not reduced. M3 was the most reduced tooth in trigonid buccolingual diameter. The percentage sexual dimorphism values were greater for the size of the talonid than for the trigonid, indicating that male values exceeded those for females by a greater amount in the later-developing crown unit. Crown dimensions were larger generally in the Aboriginal Australians from Yuendumu than in the Papua New Guinea Highlanders from Wabag, with differences being more evident in M2 and M3 than M1, especially in talonid dimensions. The trigonid, which develops early both phylogenetically and ontogenetically, tended to be relatively stable in size, whereas the later-forming talonid displayed size reduction when comparisons were made both within and between groups.     

Non-deletion haemoglobin H disease in Papua New Guinea.

Analysis of DNA from members of a Melanesian family from Papua New Guinea with haemoglobin (Hb) H disease revealed that all four alpha globin genes are intact in affected subjects. Study of restriction enzyme site and length polymorphisms and the use of oligonucleotide probes indicated that the molecular basis of this Papuan form of non-deletion Hb H disease differs from the previously described Middle Eastern and Mediterranean types.     

Dietary change and adolescent growth among the Bundi (Gende-speaking) people of Papua New Guinea

In the 1960's, the Bundi had a pattern of slow growth, delayed maturation, and small adult body size due to malnutrition. Since then, improved transportation, wage income, cash cropping, and migration have changed dietary patterns for the Bundi. The purpose of our study was to assess the effects of this general increase in protein and energy intakes on adolescent growth. The data were collected in 1984. Subscapular skinfold thicknesses among rural Bundi children measured in 1984 and 1967 confirm that nutritional status has improved, although current means for height and weight are still below the NCHS 5th percentile. Rural Bundi measure in 1984 were compared to the 1967 data for differences in height and weight. For both sexes, there were increases in growth status and/or the tempo of growth in height and weight. Urban- rural comparisons further contrast the effects of improved nutrition. For males and females, significant differences between urban and rural groups are found mainly in the age range of the adolescent growth spurt. These findings suggest earlier maturation of urban adolescents. Although interpretation of cross-sectional growth data cannot be conclusive, these results suggest that the tempo of growth is the best indicator of nutritional status during adolescenc.     

Secular trend in stature in the Portuguese population (1904-2000)

The records of height of 995 101 18-year-old Portuguese males were analysed as well as the relation between localities of the subject's residence (districts) and final height. The sample includes all the Portuguese 18-year-old males born between 1966 and 1982 and examined between 1985 and 2000, in the north, centre and south of Portugal, representing all the social strata. Statistically significant differences (p 相似文献   

Secular trend in stature in the Portuguese population (1904-2000)

The records of height of 995 101 18-year-old Portuguese males were analysed as well as the relation between localities of the subject's residence (districts) and final height. The sample includes all the Portuguese 18-year-old males born between 1966 and 1982 and examined between 1985 and 2000, in the north, centre and south of Portugal, representing all the social strata. Statistically significant differences ( p &#104 0.001) among the districts were found: males from Lisboa (172.79 cm) and Braga (172.67 cm), the most developed districts, are the tallest, and those from Madeira (170.67 cm), Castelo Branco, Leiria and Coimbra (171.31 cm) are the shortest. Comparing to published data from 1904, a positive secular trend in height was found. The average increase was 8.93 cm, which yields a rate of 0.99 cm per decade. This positive trend must be related to the general improvement in the population's standard living conditions that took place in Portugal mainly after the 1960s and 1970s, especially in terms of nutrition and the health system. However, taking into account the differences that still exist in mean height values between the districts, these results suggest that there are still great social inequalities in Portugal and the secular trend in height will continue for the Portuguese population in future decades.     

HTLV-I antibody studies in villagers in East Sepik Province,Papua New Guinea

Summary Serum samples collected in 1984 during a malariometric survey of two villages in the East Sepik Province of Papua New Guinea were tested for antibodies to HTLV-I. None of the villagers showed any symptoms suggestive of retrovirus infection. Eighteen of the 186 (9.5%) sera tested at that time were found to be positive. Blood samples were subsequently obtained from fifteen of the eighteen positives and subjected to analysis by enzyme-linked immunosorbent assay (ELISA), radioimmuno assay (RIA), radioimmunoprecipitation assay (RIPA), and Western blot (WB). Fourteen of the fifteen gave a positive ELISA response, but none were unequivocally positive by p 24 RIA. All sera tested were reactive togag antigens by WB, but gave indeterminate results currently accepted criteria. Notably absent from the WB profiles of all of the study subjects was an antibody response to HTLV-I envelope protein gp 46. It is possible that these antibody responses are directed against a variant of HTLV-I or to a novel retrovirus which possesses core antigens similar to those of HTLV-I but has different envelope antigens. Until a virus is isolated, or the viral genome is identified in infected lymphocytes, the possibility remains that the response may be due to factors unrelated to retrovirus infection.