Many developing countries are experiencing the epidemiological transition, with the majority of deaths attributed to cardiovascular disease, cancer, Type 2 diabetes (T2DM) and others. In some countries, large proportional mortality attributed to diabetes is evident in official mortality statistics, with Mauritius and Fiji rated as the highest in the world.

In view of erroneous type 2 diabetes prevalence reported in 3 small Pacific Island countries, a study was conducted to investigate whether this error occurred in other countries which have conducted WHO STEPS surveys associated with glucose thresholds for point‐of‐care (POC) measuring devices calibrated to plasma.

This study estimates type 2 diabetes (T2DM) incidence in Samoans aged 25–64 years from sequential, irregularly spaced, cross-sectional population prevalence surveys.

Aims: To estimate the overweight (OW) and obesity (Ob) prevalence and associated socio-demographic risk factors in New Caledonian adults aged 18-67 years.

Methods: From a randomly selected cross-sectional population survey, self-reported (n=2513) and measured (n=736) height and weight data were collected. Separate linear regression analyses for measured weight and height were performed, using cases with both self-reported weight and height and socio-demographic variables. The final weight and height assigned to each case was either measured or predicted from the regression (n=2075). OW prevalence was defined as: Body Mass Index (BMI) ≥25 and <30kg/m-2; and Ob: BMI ≥30kg/m-2. Samples were weighted to the general adult population. Prevalence and Odds ratios (ORs) were calculated by gender, and adjusted for socio-demographic variables, to assess differentials in OW, Ob and OW-Ob, using multinomial and logistic regressions.

Results: Male (M) OW was 35% (95% CI: 31-38), Ob 29% (95% CI: 26-32) and OW-Ob 64% (95% CI: 60-67); female (F) OW was 26% (95% CI: 23-28), Ob 34% (95% CI: 31-37) and OW-Ob 60% (95% CI: 57-63). Compared to Melanesians (OR=1.0) for male/female: Polynesians had the highest prevalence of OW (1.7/1.5), Ob (4.7/3.5), and OW-Ob (3.0/2.5); New Caledonian-born Europeans had greater OW, Ob and OW-Ob (0.3/0.4) than immigrant Europeans (0.2/0.2).

Conclusions: Findings contribute to obesity comparisons with other Pacific Islands, and they establish trends in New Caledonia for targeting policies and strategies of prevention.

Population surveys of Type 2 diabetes mellitus and obesity conducted in Samoa over three decades have used varying methodologies and definitions. This study standardizes measures, and trends of Type 2 diabetes mellitus and obesity for 1978–2013 are projected to 2020 for adults aged 25–64 years.

Disparate population surveys of type 2 diabetes mellitus (T2DM) have been conducted in Tonga for 4 decades. This study standardizes these surveys to enable assessment of T2DM and obesity trends in Tongans aged 25 to 64 years over 1973-2012, and projects T2DM prevalence to 2020 based on demographic and population weight changes. Eight surveys were standardized to the nearest census to produce nationally representative estimates. Linear period trends and prevalence projections to 2020 were produced using random-effects meta-regression. Over 1973-2012, T2DM prevalence increased from 5.2% to 19.0% (1.9%/5 years) and obesity prevalence from 56.0% to 70.2% (2.7%/5 years). T2DM prevalence period projection to 2020 is 22.3%. Based on modeling using body mass index, T2DM prevalence in 2020 could have been 12.7% and 16.8% in 2020 had mean population weight been 1 to 4 kg lower than 2012 levels.

https://www.ncbi.nlm.nih.gov/pubmed/27122623

Background: No systematic comparison has been conducted in Fiji using all suitable surveys of type 2 diabetes mellitus (T2DM) and obesity prevalence after standardizing methodology and definitions.

Methods: Unit records from six surveys of Fiji adults were variously adjusted for age, ethnicity (Fiji Melanesians, i-Taukei, and Fijians of Asian Indian descent [Indians]) and urban–rural by sex to previous censuses. Trends were assessed using meta-regression (random effect models) and estimates projected to 2020. Poisson regression of strata was used to assess the effect of body mass index (BMI) increases on T2DM period trends.

Results: Over 1980–2011, T2DM prevalence increased in i-Taukei men (3.2% to 11.1%; 1.32%/5 years) and women (5.3% to 13.6%; 1.40%/5 years) and Indian men (11.1% to 17.9%; 1.24%/5 years) and women (11.2% to 19.9%; 1.71%/5 years). Projected T2DM prevalence in 2020 is 13.3% and 16.7% in i-Taukei men and women, and 23.4% and 24.1% in Indian men and women, respectively. Obesity prevalence increased in i-Taukei men (12.6% to 28.9%; 2.99%/5 years) and women (30.1% to 52.9%; 3.84%/5 years) and in Indian men (2.8% to 9.4%; 1.21%/5 years) and women (13.2% to 26.6%; 2.61%/ 5 years). Projected obesity prevalence in 2020 is 34.0% and 60.0% in i-Taukei and women, and 11.4% and 31.0% in Indian men and women, respectively. After age-adjustment, an estimated 27%, 25%, 16% and 18% of the T2DM period trend is attributable to BMI in i-Taukei men and women and Indian men and women, respectively.

Conclusions: Prevalence of T2DM in Fiji is projected to continue increasing, driven by rising obesity, with consequences for premature mortality and life expectancy.

https://www.ncbi.nlm.nih.gov/pubmed/26201444

Background: Type 2 diabetes mellitus (T2DM) incidence is traditionally derived from cohort studies that are not always feasible, representative, or available. The present study estimates T2DM incidence in Fijian adults from T2DM prevalence estimates assembled from surveys of 25–64 year old adults conducted over 30 years (n = 14,288).

Objective: To assemble standardized estimates of abnormal glucose tolerance in adults in diverse communities worldwide and provide guidelines for the derivation of comparable estimates in future epidemiological studies.

Research design and methods: The project was limited to population-based investigations that had used current WHO criteria for diagnosis and classification of abnormal glucose tolerance. Raw data were obtained by WHO from surveys conducted during 1976-1991 of over 150,000 persons from 75 communities in 32 countries. Data within the truncated age range of 30-64 yr were adjusted to the standard world population of Segi. Age-specific prevalences also are reported for selected populations.

Results: Within the chosen age range, diabetes was absent or rare (< 3%) in some traditional communities in developing countries. In European populations, age-standardized prevalence varied from 3 to 10%. Some Arab, migrant Asian Indian, Chinese, and Hispanic American populations were at higher risk with prevalences of 14-20%. The highest prevalences were found in the Nauruans (41%) and the Pima/Papago Indians (50%). Age-standardized prevalence of IGT was low (< 3%) in some Chinese, traditional American Indian, and Pacific island populations. Moderate (3-10%) or high (11-20%) prevalences of IGT were observed in many populations worldwide. The highest estimates for prevalence of IGT were seen in female Muslim Asian Indians in Tanzania (32%) and in urban male Micronesians in Kiribati (28%). Prevalence of diabetes rose with age in all populations in which age-specific data were examined. This trend was most pronounced in those at moderate to high risk. The ratio of prevalence of diabetes in men versus women varied markedly between populations with little discernable trend, although IGT was generally more common in women. In most communities, at least 20% of diabetes cases were unknown before the survey, and in many communities, > 50% were previously undiagnosed. In both Chinese and Indian migrant populations, relative prevalence was high when compared with indigenous communities.

Conclusions: Diabetes in adults is now a global health problem, and populations of developing countries, minority groups, and disadvantaged communities in industrialized countries now face the greatest risk. https://www.ncbi.nlm.nih.gov/pubmed/8123057

Objective: To determine the prevalence of non-communicable disease, specifically hypertension, diabetes and obesity, amongst populations at different levels of urbanisation in Vanuatu, and to relate the frequency of these conditions to the modernisation of way of life.

Design: A cross-sectional population-based comparative study of indicative cluster samples.

Setting: Republic of Vanuatu (south-west Pacific). A relatively undeveloped malarious island country.

Participants: Adult (aged greater than or equal to 20 years) Melanesian ni-Vanuatu of both sexes. An occupation-based (civil servants) urban sample (n = 623) and area-based semi-rural (n = 349) and rural (n = 397) samples were employed. Response rates were 78%-92%.

Interventions: Cases detected were referred for assessment and treatment by local medical staff.

Main outcome measures: Body mass index, triceps skinfold thickness, blood pressure, plasma glucose (fasting and 2 hours after 75 g glucose), plasma cholesterol and triglyceride levels.

Results: Modernity scores confirmed that the three locations represented different levels of acculturation. Prevalences of non-communicable disease were relatively low compared to other Pacific Island communities and industrialised countries. These conditions were nevertheless more common in the urban sample and least common in the rural sample. Non-communicable disease correlated positively with modernity scores and negatively with physical activity scores. Obesity correlated with blood pressure in the urban sample, and there was indirect evidence (urine sodium concentration) of higher salt intake with modernisation. Mean plasma cholesterol levels were lowest in the rural group.

Conclusion: Prevalences of non-communicable disease are relatively low in Vanuatu, although rural-urban differentials are present, and likely to increase with continued development. The evidence presented is consistent with non-communicable disease being related to the modernisation of way of life; specifically: decreased exercise, obesity, and dietary change. Preventive activities should commence now. https://www.ncbi.nlm.nih.gov/pubmed/1857313

Since 1988, WHO has been collecting standardized information on the prevalence of diabetes mellitus and impaired glucose tolerance (IGT) in adult communities worldwide. Within the age range 30-64 years, diabetes and IGT were found to be absent or rare in some traditional communities in Melanesia, East Africa and South America. In communities of European origin, the prevalences of diabetes and IGT were in the range of 3-10% and 3-15% respectively, but migrant Indian, Chinese and Hispanic American groups were at higher risk (15-20%). The highest risk was found in the Pima Indians of Arizona and in the urbanized Micronesians of Nauru, where up to one-half of the population in the age range 30-64 years had diabetes. The prevalence of total glucose intolerance (diabetes and IGT combined) was greater than 10% in almost all populations, and was within the range 11-20% for European and U.S. white populations. However, the prevalence of total glucose intolerance reached almost 30% in Arab Omanis and in U.S. blacks and affected one-third of all adult Chinese Mauritians, migrant Indians, urban Micronesians and lower-income urban U.S. Hispanics. In Nauruans and Pima Indians, approximately two-thirds of all adults in the age range were affected. These results lead to three important conclusions. (1) An apparent epidemic of diabetes has occurred-or is occurring-in adult people throughout the world. (2) This trend appears to be strongly related to life-style and socioeconomic change. (3) It is the populations in developing countries, and the minority or disadvantaged communities in the industralized countries who now face the greatest risk. Diabetes in adults should now be considered not only as a disease of industrialized countries, but also as a Third World problem. All countries should be encouraged to develop national policies and programmes for the prevention and control of this costly disease. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2393324/

Plasma uric acid was investigated in a population survey on diabetes and cardiovascular risk factors among Melanesians and Asian Indians in Fiji in 1980. Plasma uric acid levels were elevated in men and women with impaired glucose tolerance in both ethnic groups. The lowest plasma uric acid levels were found in diabetic patients, especially in diabetic men. Even though obesity was positively associated with plasma uric acid, it did not explain the high plasma uric acid level in persons with impaired glucose tolerance. Body mass index had a significant and independent impact on plasma uric acid levels both in nondiabetic and diabetic men and women. The strongest predictor of plasma uric acid in the multiple regression analysis in our study populations was plasma creatinine: it alone explained 9% of the variation in men and 2% in women; and 24% in Melanesians and 5% in Asian Indians. Our findings suggest a strong renal involvement in the balance of plasma uric acid and may also reflect certain dietary patterns, such as a high intake of protein, fats, and certain local vegetables. Although the prevalence of hyperuricemia was high, 27% in both Melanesian men and women, 22% in Asian Indian men, and 11% in Asian Indian women, clinical gout was uncommon. Many predictor variables and their interactions were analyzed along with the reasons for the high plasma uric acid levels in persons with impaired glucose tolerance and for the low plasma uric acid levels in diabetic patients. https://www.ncbi.nlm.nih.gov/pubmed/3337086

Data on five Polynesian populations, obtained by standardized population surveys conducted during the years 1978-1980, were examined for associations between glucose tolerance and both obesity and island of residence. In both sexes, after allowing for the influence of age and obesity, there was a significant difference in glucose tolerance between the three populations considered, subjectively, to be the less traditional and the two considered as retaining a more traditional lifestyle. Regression models predicting diabetic status were weaker than those using glucose tolerance as the dependent variable, probably due to the small number of diabetic subjects in the samples. As all subjects were of Polynesian ancestry, and the results could not be explained by knowledge of ancestral affiliations between the five populations, environmental, rather than genetic factors may have been the determinants of the observed differences in glucose tolerance. This finding highlights the need for a more sophisticated approach to the study of the association between socio-cultural modernization and chronic disease in the Pacific. https://www.ncbi.nlm.nih.gov/pubmed/3342733

A comparative study of diabetes, impaired glucose tolerance and obesity was undertaken in samples of rural Wallisians of Wallis Island and first generation Wallisian migrants in the urban centre of Noumea, New Caledonia. Approximately 20–25% of the adult population of the 2 communities was included in the study.
Wallisians in Noumea tended to be more obese than those in Wallis (particularly females). The prevalence of diabetes was 7 and 4 times higher in Noumea compared to Wallis for males and females respectively. Differences in the extent of obesity appeared to account for some of the difference in prevalence of diabetes, but other environmental factors (such as constituents of the diet, and exercise) must be operative as well.
The results of this study are consistent with previous findings concerning environmental determinants of diabetes in Pacific populations. http://europepmc.org/abstract/MED/3836104

A population-based survey of 2938 subjects has demonstrated a high prevalence of non-insulin-dependent diabetes (NIDDM) in the Micronesian population of Kiribati (formerly the Gilbert Islands). This finding provides further support for evidence from Nauru, Guam, and the Marshall Islands that Micronesians are particularly susceptible to NIDDM. The age-standardized prevalence was over twice as high in an urban, as compared with a rural, sample (9.1 versus 3.0 in men, 8.7 versus 3.3 in women). To test the a priori hypotheses that obesity, reduced physical activity, and a nontraditional diet are associated with NIDDM, indices of these factors were compared in rural and urban subjects. The rural population was found to be leaner, to have a higher estimate of habitual physical activity, and to have a lower percentage of daily energy intake derived from imported foods. Further analysis demonstrated that obesity alone was insufficient to explain the rural-urban difference in prevalence of NIDDM. The multiple logistic regression model demonstrated a significant association between the prevalence of NIDDM and both obesity and urbanization in men. In women, obesity, physical inactivity, and urbanization were all associated with increased prevalence of NIDDM. https://www.ncbi.nlm.nih.gov/pubmed/6499635

In Fiji Melanesian and Indian men, prevalence of diabetes is more than twice as high in those graded as sedentary or undertaking light activity as in those classed as performing moderate or heavy exercise. This difference was present in both ethnic groups, and maintained when age, obesity, and urban/rural- status were taken into account. It is concluded that, in the population under study, there is epidemiological evidence for the role of physical inactivity as an independent risk factor for Type 2 (non-insulin-dependent) diabetes. https://www.ncbi.nlm.nih.gov/pubmed/6530053

Population-based data on 1,842 subjects from six semitraditional Pacific communities, collected in the years 1978–1983, have been compared in order to examine the hypotheses that differences in the distribution of plasma glucose concentration between populations are to some extent genetically determined, and that non-Austronesian (NAN) Melanesians are relatively resistant to glucose intolerance. Semitraditional communities were chosen for study so that the comparison would be minimally confounded by either known or as yet undetermined environmental factors associated with nontraditional living, the effects of which may vary between populations. The samples were also selected so as to provide a gradient of proportional NAN and AN admixture. They were drawn from the following regions: the highlands of Papua New Guinea, New Caledonia, Fiji, the Wallis Islands, Western Samoa, and Kiribati (formerly the Gilbert Islands). The Papua New Guinea highlanders, of entirely NAN ancestry, were regarded as the baseline population.
A gradient of increasing mean 2-hr plasma glucose concentration was observed across the six populations and differences persisted between populations, after controlling for age and obesity. Variations in diet, physical activity, and degree of sociocultural modernization were not considered a sufficient or consistent explanation of these findings and they therefore lend tentative support to the hypothesis of a genetic component to variability in glucose tolerance.
The relationship between population estimates of glucose tolerance and estimates of the genetic distance from the baseline NAN Melanesian sample was examined. With the notable exception of Fiji, there was evidence of a linear correlation between the two parameters. http://onlinelibrary.wiley.com/doi/10.1002/gepi.1370010404/abstract

The prevalence of diabetes mellitus in the traditional-living population of Wallis Island was low and comparable with that found in other rural Polynesian societies. The diabetes prevalence was 1.9% in men and 3.5% in women; impaired glucose tolerance occurred in 5.0% of men and 8.4% of women. The prevalence of obesity was significantly greater in women than in men (37.4% versus 12%, respectively, were equal to or greater than 140% ideal weight). Subjects with diabetes tended to be more obese and less active than normal subjects, but these differences, although appreciable, were not usually statistically significant. The population engages in considerable physical activity, and this, along with the traditional diet, may be responsible for the relatively low diabetes prevalence. https://www.ncbi.nlm.nih.gov/pubmed/6617409

Rural-urban and ethnic comparisons of impaired glucose tolerance and diabetes mellitus were made in the biracial population of Fiji in 1980. No statistically significant differences existed in age-standardized impaired glucose tolerance prevalence between rural and urban groups or between Melanesians and Indians. The age-standardized prevalence of diabetes in the rural Melanesian male population was one-third that of the urban male population (1.1 vs. 3.5%). In females, there was a sixfold rural-urban difference (1.2 vs. 7.1%). By contrast, rural and urban Indians had similar rates (12.1 vs. 12.9% for males; 11.3 vs. 11.0% for females). Standardization of two-hour plasma glucose for age and obesity did not eliminate the rural-urban difference in plasma glucose concentration for Melanesian males and females. The results in Melanesians confirm previously reported rural-urban diabetes prevalence differences, and suggest that factors other than obesity, such as differences in physical activity, diet, stress, or other, as yet undetermined, factors contribute to this difference. The absence of a rural-urban difference in diabetes prevalence in Indians may suggest that genetic factors are more important for producing diabetes in this ethnic group, or that causative environmental factors such as diet operate similarly upon both the rural and the urban populations. https://www.ncbi.nlm.nih.gov/pubmed/6637994

 

This report gives the prevalence rates of impaired glucose tolerance (IGT) and diabetes mellitus (DM) for several Micronesian, Polynesian, and Melanesian populations in the Pacific region according to the new WHO criteria.
The Micronesian population of Nauru show the highest prevalence rates of both IGT (22.7%) and DM (30.3%) - 53% of the adult population thus demonstrating abnormal glucose tolerance. The lowest prevalence rates of both IGT (4.5%) and DM (1.5%) were seen in the rural Melanesian population of the main island of New Caledonia. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2535962/
 

We have analyzed data from 3370 OGTTs performed during epidemiologic studies in three different ethnic groups (Micronesian, Polynesian, and Melanesian) in various Pacific countries to examine the value of a single fasting plasma glucose greater than or equal to 140 mg/dl as a diagnostic test for diabetes (defined as 2-h plasma glucose greater than or equal to 200 mg/dl). A fasting plasma glucose greater than or equal to 140 mg/dl is a highly specific test for diabetes, specificity in the various populations ranging from 98.1% to 99.7%. On the other hand, the sensitivity of fasting plasma glucose was not high and varied greatly between the populations (46.2%-79.0%). The predictive value of fasting plasma glucose for the diagnosis of diabetes was lowest in populations with a low diabetes prevalence and improved in higher prevalence groups. These data indicate that a fasting plasma glucose greater than or equal to 140 mg/dl is not a good screening test, apart from populations with a high prevalence of diabetes mellitus, and the 2-h postload plasma glucose is preferable. https://www.ncbi.nlm.nih.gov/pubmed/7347665

An epidemiologic survey of 133 adult Polynesians of Manihiki Atoll, Cook Island group, revealed a high prevalence of diabetes mellitus (males 8.0 percent, females 10.3 percent) and impaired glucose tolerance (males 8.0 percent, females 31.0 percent). Those with abnormal glucose tolerance were older, more obese, and engaged in less physical activity than normals. The females had a higher prevalence of both diabetes and impaired glucose tolerance than the males. Although Manihiki is geographically isolated, the islanders have a good income from copra and pearl shell. The change from a traditional to a modern way of life in a population with an increase susceptibility to diabetes is the probable cause of the high prevalence of abnormal glucose tolerance. The change in living patterns is a consequence of change from a subsistence existence to involvement in the cash economy. https://www.ncbi.nlm.nih.gov/pubmed/6950276

The prevalence of abnormal glucose tolerance in the Polynesian population of Funafuti, Tuvalu (formerly the Ellice Islands) is much higher in females than males. However, the women are more obese than the men. Adjusting for obesity reduced the relative risk of abnormal glucose tolerance between males and females but the differences remained statistically significant. It is concluded that differences in the extent of obesity in the male and female population of Tuvalu explain part (but not all) of the differences in prevalence of impaired glucose tolerance in Funafutians. https://www.ncbi.nlm.nih.gov/pubmed/6945509