Obesity measures in the Kiribati population: a need to reclassify body mass index cut-points.

BACKGROUND: Obesity is a public health problem in Micronesia. The objective of the study was to assess obesity, the relationship between body mass index (BMI) and body fat percentage (BF%) among adults, and determine the appropriate BMI cut-points in Kiribati. METHODS: A cross-sectional study was undertaken among 483 adults randomly selected from South Tarawa (ST) and Butaritari (BT). Weight, height, BF% and physical activity level (PAL) was measured using standard methods. Linear and quadratic regression analyses were conducted to assess the association between BF% and BMI whilst controlling for age and gender. Receiver operating characteristics (ROC) curve analyses were used to assess whether for the Kiribati population alternative BMI cut-off points for obesity are needed. RESULTS: Approximately 75% of participants were obese using standard BMI and BF% cut-offs, with the highest prevalence observed in South Tarawa. BF% was significantly (p < 0.001) and positively associated with age (males, r = 0.78; females, r = 0.67; p < 0.001) and BMI. Based on ROC-curve analyses the BMI cut-offs for predicting high BF% among I-Kiribati people were 24.5 kg/m2 for males and 32.9 kg/m2 for females. CONCLUSIONS: In conclusion, the majority of adults in Kiribati were either obese or overweight and had high BF%. We suggest that ethnic-specific BMI cut-points to define obesity for the population of Kiribati may be more appropriate than the currently used international cut-points.

Siblings, asthma, rhinoconjunctivitis and eczema: a worldwide perspective from the International Study of Asthma and Allergies in Childhood.

BACKGROUND: Associations of larger families with lower prevalences of hay fever, eczema and objective markers of allergic sensitization have been found fairly consistently in affluent countries, but little is known about these relationships in less affluent countries. METHODS: Questionnaire data for 210,200 children aged 6-7 years from 31 countries, and 337,226 children aged 13-14 years from 52 countries, were collected by Phase Three of the International Study of Asthma and Allergies in Childhood (ISAAC). Associations of disease symptoms and labels of asthma, rhinoconjunctivitis and eczema were analysed by numbers of total, older and younger siblings, using mixed (multi-level) logistic regression models to adjust for individual covariates and at the centre level for region, language and national affluence. RESULTS: In both age groups, inverse trends (P < 0.0001) were observed for reported 'hay fever ever' and 'eczema ever' with increasing numbers of total siblings, and more specifically older siblings. These inverse associations were significantly (P < 0.005) stronger in more affluent countries. In contrast, symptoms of severe asthma and severe eczema were positively associated (P < 0.0001) with total sibship size in both age groups. These associations with disease severity were largely independent of position within the sibship and national GNI per capita. CONCLUSIONS: These global findings on sibship size and childhood asthma, rhinoconjunctivitis and eczema suggest at least two distinct trends. Inverse associations with older siblings (observations which prompted the 'hygiene hypothesis' for allergic disease) are mainly a phenomenon of more affluent countries, whereas greater severity of symptoms in larger families is globally more widespread.

Global variation in the prevalence and severity of asthma symptoms: phase three of the International Study of Asthma and Allergies in Childhood (ISAAC).

BACKGROUND: Phase Three of the International Study of Asthma and Allergies in Childhood (ISAAC) measured the global prevalence and severity of asthma symptoms in children. METHODS: A cross-sectional questionnaire survey of 798 685 children aged 13-14 years from 233 centres in 97 countries, and 388 811 children aged 6-7 years from 144 centres in 61 countries, was conducted between 2000 and 2003 in >90% of the centres. RESULTS: The prevalence of wheeze in the past 12 months (current wheeze) ranged from 0.8% in Tibet (China) to 32.6% in Wellington (New Zealand) in the 13-14 year olds, and from 2.4% in Jodhpur (India) to 37.6% in Costa Rica in the 6-7 year olds. The prevalence of symptoms of severe asthma, defined as >or=4 attacks of wheeze or >or=1 night per week sleep disturbance from wheeze or wheeze affecting speech in the past 12 months, ranged from 0.1% in Pune (India) to 16% in Costa Rica in the 13-14 year olds and from 0% to 20.3% in the same two centres, respectively, in the 6-7 year olds. Ecological economic analyses revealed a significant trend towards a higher prevalence of current wheeze in centres in higher income countries in both age groups, but this trend was reversed for the prevalence of severe symptoms among current wheezers, especially in the older age group. CONCLUSION: Wide variations exist in the symptom prevalence of childhood asthma worldwide. Although asthma symptoms tend to be more prevalent in more affluent countries, they appear to be more severe in less affluent countries.

Reduction in asthma morbidity following a community-based asthma self-management programme in Tonga.

BACKGROUND: The Tonga Asthma Self-management Project assessed whether the introduction of an asthma self-management plan would reduce asthma morbidity. METHODS: The project involved a 'before and after' trial, with each participant serving as his/her own control. Asthma patients used the self-management plan to manage their asthma medication or obtain medical help based on their peak expiratory flow (PEF) rate and/or asthma symptoms. RESULTS: The 110 participants initially had relatively high asthma morbidity: 68% had had an emergency medical visit for asthma in the previous 12 months. Ninety-two (84%) completed the 12-month programme. Emergency doctor visits fell from 66% in the previous 12 months to 18% (P < 0.001) in the following 12 months. Other measures also improved, including hospital admissions (from 19% to 3%, P = 0.001), having 14 days or more 'out of action' (from 29% to 4%, P < 0.001), waking > or = 2 nights a week (from 40% to 13%, P < 0.001), severe asthma attacks (from 54% to 18%, P < 0.001) and mean PEF rates (from 341 l/min to 417 l/min, a 22% increase, P < 0.001). CONCLUSIONS: The potential benefits of asthma self-management plans and community-based asthma education are supported by the findings of the Tonga study. Their implementation is essential in the resource-scarce Pacific health setting.

Risk factors for symptoms of childhood asthma, allergic rhinoconjunctivitis and eczema in the Pacific: an ISAAC Phase III study.

BACKGROUND AND METHODS: Phase III of the International Study of Asthma and Allergies in Childhood (ISAAC) was conducted in eight Pacific countries, five of which (Samoa, Fiji, Tokelau, French Polynesia and New Caledonia) collected environmental questionnaire (EQ) data. We report the findings of the EQ analyses below. RESULTS: The major factors associated with current wheeze were regular margarine consumption (prevalence odds ratio [POR] 1.19, 95%CI 1.01-1.40), paracetamol use (POR 1.35, 95%CI 1.11-1.64), electric cooking (POR 1.42, 95%CI 1.11-1.80), regular exercise (POR 1.44, 95%CI 1.18-1.75) and maternal smoking (POR 1.16, 95%CI 1.01-1.33). Protective factors included having older siblings (two or more POR 0.69, 95%CI 0.58-0.82; one POR 0.86, 95%CI 0.71-1.05), and being born in the country of the survey (POR 0.74, 95%CI 0.63-0.87). Risk factors for rhinoconjunctivitis included regular consumption of meat, butter, margarine and nuts, regular exercise, regular television viewing, paracetamol use and passive smoking. Eczema was associated with regular meat, pasta and butter consumption, regular television viewing, paracetamol use and passive smoking. CONCLUSIONS: Regular meat and margarine consumption, paracetamol use, electric cooking and passive smoking are risk factors for symptoms of asthma, rhinoconjunctivitis and eczema in the Pacific. However, most of these associations were weak, and account for only a small proportion of cases.

Prevalence of symptoms of childhood asthma, allergic rhinoconjunctivitis and eczema in the Pacific: the International Study of Asthma and Allergies in Childhood (ISAAC).

The International Study of Asthma and Allergies in Childhood (ISAAC) has provided valuable information regarding international prevalence patterns and potential risk factors for asthma, allergic rhinoconjunctivitis and eczema. However, the only Pacific countries that participated in ISAAC Phase I were Australia and New Zealand, and these included only a small number of Pacific children. Phase III has involved not only repeating the Phase I survey to examine time trends, but also to include centres and countries which are of interest but did not participate in Phase I. The ISAAC Phase III study was therefore conducted in the Pacific (in French Polynesia, New Caledonia, Tonga, Fiji Islands, Samoa, Cook Islands, Tokelau Islands and Niue). The overall prevalence rates of current symptoms (in the last 12 months) were 9.9% for asthma, 16.4% for allergic rhinoconjunctivitis and 10.7% for atopic eczema. The prevalence of current wheezing (9.9%) was generally much lower than that has been observed in Pacific children in New Zealand (31%), but there was considerable variation between the various Pacific centres: Tokelau Islands (19.7%), Tonga (16.2%), Niue (12.7%), French Polynesia (11.3%), Cook Islands (10.6%), Fiji Islands (10.4%), New Caledonia (8.2%) and Samoa (5.8%). The reasons for these differences in prevalence across the Pacific are unclear and require further research. The finding that prevalence levels are generally considerably lower than those in Pacific children in New Zealand adds to previous evidence that children who migrate experience an altered risk of asthma as a result of exposure to a new environment during childhood.

Prevalence of hepatitis B virus infection in Tonga: identifying high risk groups for immunization with hepatitis B vaccine.

A serological survey for evidence of hepatitis B virus (HBV) infection was conducted in the Kingdom of Tonga as the first step in developing a strategy for an immunization programme. There were 414 individuals from the general population plus 137 pregnant women included in the survey. HBsAg was found in 20% of the general population and 88% had one or more serologic markers of HBV infection. In the 5-9 year age group, 80% of the children had one or more markers of HBV, and in the 10-19 year age group, the prevalence was 96.4%, indicating that most transmission of HBV in the Tongans studied occurs in the young. Of the pregnant women studied, 15% were positive for HBsAg, and 57% of those positive for HBsAg were also positive for HBeAg. Evidence of delta virus infection was not found in any of 82 HBsAg positive sera tested. Surveillance data suggested that significant serious sequelae to HBV infection (cirrhosis and primary hepatocellular carcinoma) also occur in Tonga. Immunization of infants and children is the most effective strategy for reducing or eliminating HBV infection and its sequelae in developing countries like Tonga.