Christine Linhart

Diabetes and obesity trends in Fiji over 30 years

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.

Divergent mortality trends by ethnicity in Fiji.

Objective: To examine trends in infant mortality rate (IMR), adult mortality and life expectancy (LE) in the two major Fijian ethnic groups since 1975.

Trends in diabetes and obesity in Samoa over 35 years, 1978-2013

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.

Continued increases in hypertension over three decades in Fiji, and the influence of obesity

Objectives: To analyse trends during 1980–2011 in hypertension prevalence and SBP/DBP by sex in Fiji Melanesian (i-Taukei) and Indian adults aged 25–64 years; and to assess effects of BMI. Methods: Unit record data from five population-based surveys were included (n = 14 191). Surveys were adjusted to the nearest previous census to improve national representativeness. Hypertension was defined as SBP at least 140 mmHg and/or DBP at least 90 mmHg and/or on medication for hypertension. Regression (Poisson and linear) was used to assess period trends. Results: Over 1980–2011 hypertension prevalence (%) and mean blood pressure (BP) (SBP/DBP mmHg) increased significantly (P < 0.001) in both sexes and ethnicities. Increases in hypertension were: from 16.2 to 41.3% in i-Taukei men (mean BP from 122/73 to 135/81); from 20.5 to 37.8% in Indian men (mean BP from 122/74 to 133/81); from 25.9 to 36.9% in i-Taukei women (mean BP from 126/76 to 132/81); and from 17.6 to 33.1% in Indian women (mean BP 117/71 to 130/81). The age-adjusted trend in hypertension and mean BP (over 32 years) declined after adjusting for BMI, with effects of obesity greater in women than men, and in Indians than i-Taukei. BMI explained 45% of the age-adjusted increase in DBP over the period in Indians (both sexes), and 16% (men) and 38% (women) in i-Taukei. Conclusion: Significant increases have occurred in hypertension prevalence and SBP/DBP in both sexes and ethnicities of Fiji during 1980–2011 with no indication of decline, contributing to significant premature mortality from cardiovascular disease.

Erroneous inflation of diabetes prevalence: Are there global implications?

Comparison of the prevalence of type 2 diabetes mellitus (T2DM) in adults aged 25-64 years in selected Pacific Island countries using whole blood and plasma glucose cut-off points. Unit records of STEPwise approach to Surveillance (STEPS) surveys obtained from Fiji, Samoa, and Tonga Ministries of Health; T2DM prevalence recalculated using whole blood and plasma cut-off points. Shaded bars indicate T2DM prevalence based on correct glucose cut-off points for the glucose meter used (fasting blood glucose [FBG] ≥6.1 mmol/L for early surveys1,3,5 ; fasting plasma glucose [FPG] ≥7.0 mmol/L for later surveys),2,4,6 whereas open bars show T2DM prevalence based on incorrect glucose cut-off points (FPG ≥6.1 mmol/L for later surveys).2,4,6 Highlights Incorrect glucose cut-off points were applied to the Fiji 2011, Samoa 2013, and Tonga 2012 STEPS surveys. This doubled the actual T2DM prevalences compared to using the correct glucose cut-off points. The errors occurred due to modern glucose meters producing measurements in plasma-equivalent concentrations from whole blood samples. The incorrect whole blood glucose cut-off (≥6.1mmol/L) was applied instead of the correct plasma glucose cut-off (≥7.0mmol/L). This error likely affects other Pacific states, and may have global ramifications.

Diabetes and Obesity Trends in Tonga Over 40 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.

Changes in cardiovascular disease risk factors over 30 years in Polynesians in the French Pacific Territory of Wallis Island.

Background Wallis Island is part of a French Territory in the South Pacific. In 1980 the prevalence of hypertension and type 2 diabetes mellitus (T2DM) was low, consistent with a subsistence economy. Considerable social and economic changes have occurred over the last 30 years. Methods Survey data from 1980 and 2009 were analysed by sex in 10-year age groups, and 25–64 years age-standardised to the 2008 Census. Means and prevalences were calculated for blood pressure, fasting plasma glucose, body mass index (BMI), blood cholesterol and triglycerides as risk factors contributing to cardiovascular disease. Results During 1980–2009 there were significant increases (p < 0.05) in age-standardised means and prevalences of blood pressure and hypertension, fasting plasma glucose and T2DM, BMI and obesity, blood cholesterol (men) and triglycerides; and non-significant increases in mean diastolic blood pressure and fasting plasma glucose in women. Mean cholesterol and the prevalence of elevated cholesterol declined in women. Hypertension prevalence increased from 12% to 43% in men and from 15% to 30% in women, with 42% of the increase in men and 33% of the increase in women statistically explained by increases in BMI. T2DM increased from 2.3% to 12.2% in men and from 4.0% to 15.8% in women, with 35% of the increase in men and 26% of the increase in women statistically explained by increases in BMI. Conclusions Risk factors for cardiovascular disease have increased considerably in Wallis Island over the past 30 years, consistent with modernisation in way of life.

Diabetes incidence and projections from prevalence surveys in Samoa over 1978–2013

ObjectivesThis study estimates type 2 diabetes (T2DM) incidence in Samoans aged 25–64 years from sequential, irregularly spaced, cross-sectional population prevalence surveys.MethodsT2DM prevalence from eight population surveys conducted over 1978–2013 (n = 12,516) was adjusted for census region, sex, and 5-year age group to the nearest previous census. Annual T2DM incidence was calculated from adjusted prevalences (by sex), using birth cohorts constructed from age-period matrices. Projections of T2DM incidence to 2020 were estimated, based on various scenarios of population weight change using Poisson regression.ResultsOver 1978–2013, T2DM incidence was estimated to increase from 1.12 to 8.44 per 1000 person-years in men and from 2.55 to 8.04 per 1000 in women. Based on regression modeling, if mean population weight was stabilized from 2013, absolute incidence reductions of 0.9 per 1000 person-years (7% lower) are predicted in 2020, compared to the current period trend in weight gain.ConclusionsT2DM incidence can be calculated from irregularly conducted population risk factor surveys which may be useful in developing countries with limited resources.

Differentials in Cardiovascular Risk Factors and Diabetes by Socioeconomic Status and Sex in Kalutara, Sri Lanka

Since 1950, cardiovascular disease (CVD) has emerged as a leading cause of mortality in Sri Lanka, especially in men. In 2014, a survey in Kalutara to assess CVD and type 2 diabetes mellitus (T2DM) risk factors in adults aged 25 to 64 years (n = 1011), and associations with sex and socioeconomic status (SES), found similar CVD risk factors in both sexes, except for daily tobacco smoking at 19% in men and nil in women, and higher body mass index (BMI) in women than men. With increasing SES in men, there were significant linear increases in mean BMI, waist circumference, mean systolic and diastolic blood pressure, mean fasting plasma glucose, and T2DM prevalence, but decreases in tobacco smoking. Whereas in women higher SES was associated with a significant increase in mean BMI, but a significant decrease in hypertension prevalence. Tobacco smoking is the main risk factor explaining higher CVD mortality in men compared with women.

Declines and plateaux in smoking prevalence over three decades in Fiji

Abstract Objectives To examine trends from 1980 to 2011 in daily tobacco smoking by sex, ethnicity, age, and urban/rural in Fiji Melanesian (i-Taukei) and Indian adults aged 25–64 years. Methods Unit record data from five population-based surveys (n = 14 528) allowed classification of participants as: (1) never-smoker, ex-smoker, or non-daily smoker; or (2) daily smoker, reporting smoking <20 or ≥20 tobacco products (cigarettes/cigars/pipes) a day. Trends were examined using spline analyses. Results Over 1980–2011 the prevalence of reported daily tobacco smoking decreased significantly in both sexes and ethnicities, with the greatest decline during 1980–2000. Declines were from 81.7% to 27.0% in i-Taukei men; 55.3% to 26.3% in Indian men; 48.1% to 9.5% in i-Taukei women; and 13.8% to 1.3% in Indian women (p < .0001). Declines were consistent across all age groups in men, while there were greater declines among older age groups in women; and greater declines from higher prevalences in rural compared to urban areas in both sexes and ethnicities. Smoking ≥20 tobacco products per day declined significantly in i-Taukei men from 8.0% to 1.9% (p < .0001); there were also declines in Indian men (4.6% to 2.0%) and i-Taukei women (2.6% to 0.6%), but these were not statistically significant; and Indian women remained <0.2% throughout the period. Conclusions Significant declines in daily tobacco smoking have occurred in Fiji in both sexes and ethnicities during the past 30 years, which is consistent with declines in tobacco apparent consumption and household expenditure. However, prevalence remains high in men at around 27% in 2011, with plateau at this level in i-Taukei. Implications This is the first study to show nationally representative population trends in tobacco smoking in a developing country over such a long period (>30 years) based on empirical unit record data (n = 14 528). Cardiovascular disease is a leading cause of mortality throughout the Pacific Island region. This is the first study to show evidence of substantial declines over several decades in a cardiovascular disease risk factor in a Pacific Island country, and provides important evidence for further research into the interventions and events which may have facilitated this decline.