PRESOLRE: study protocol for a primary school-based, cluster randomised controlled trial of three sun exposure risk prevention strategies on Reunion Island.

INTRODUCTION: Reunion Island, a French overseas department, is located in the southern hemisphere, close to the Capricorn tropic. This island has a multicultural and multiethnic population of 860 000 inhabitants, a quarter of whom are at high risk of developing skin cancer due to intense ultraviolet radiation. Melanoma is responsible for the majority of skin cancer deaths. The early prevention of melanoma is based on sun protection in childhood, but French regulations are not adapted to the environmental conditions of this tropical region.The main objective of our study is to evaluate the effectiveness of three sun protection programs conducted in Reunionese primary schools through a pupil knowledge questionnaire. METHODS AND ANALYSIS: PRESOLRE is an interventional, open-label, cluster-randomised controlled trial, in four parallel arms, that is being conducted throughout 2022-2023 on Reunion Island. The trial design assumes an escalation interventional effect using: first, a control arm without proposed intervention (arm 1); second, an arm whose classes are encouraged to use the validated educational programme 'Living With the Sun' (LWS) (arm 2); third, an arm whose classes are encouraged to use both 'LWS' combined with 'Mission Soleil Réunion's sun protection awareness programme (arm 3); fourth, an arm benefiting from an intervention similar to arm 3, combined with the distribution of hats, sunglasses and sun creams (arm 4). In all, 1780 pupils from 18 classes of 20 pupils, on average, will be included. Randomisation applies to the classes of pupils (so defined as clusters). The primary outcome is based on the proportion of correct answers to the knowledge questions after the awareness programme, compared between the four arms using a linear mixed model with random intercept. ETHICS AND DISSEMINATION: The study obtained ethics approval in 2022 (ID: 2022-A00350-43). Results will be published in peer-reviewed journals. TRIAL REGISTRATION NUMBER: NCT05367180.

Usefulness of Home Screening for Promoting Awareness of Impaired Glycemic Status and Utilization of Primary Care in a Low Socio-Economic Setting: A Follow-Up Study in Reunion Island.

BACKGROUND: Low socio-economic settings are characterized by high prevalence of diabetes and difficulty in accessing healthcare. In these contexts, proximity health services could improve healthcare access for diabetes prevention. Our primary objective was to evaluate the usefulness of home screening for promoting awareness of impaired glycemic status and utilization of primary care among adults aged 18-79 in a low socio-economic setting. METHODS: This follow-up study was conducted in 2015-2016 in Reunion Island, a French overseas department in the Indian Ocean. Enrollment and screening occurred on the same day at the home of participants (N=907). Impaired glycemic status was defined as [glycated hemoglobin (HbA1c) ≥5.7%] OR [fasting capillary blood glucose (FCBG) ≥1.10 g/L] OR [HbA1c=5.5-5.6% and FCBG=1.00-1.09 g/L]. Medical, socio-cultural, and socio-economic characteristics were collected via a face-to-face questionnaire. A one-month telephone follow-up survey was conducted to determine whether participants had consulted a general practitioner (GP) for confirmation of screening results. A multinomial polytomous logistic regression model was used to identify factors independently associated with non-use of GP consultation for confirmation of screening results and nonresponse to the telephone follow-up survey. RESULTS: Prevalence of glycemic abnormalities was 46.0% (95% CI = 42.7-49.2%). Among participants with impaired glycemic status (N=417), 77.7% (95% CI=73.7-81.7%) consulted a GP for confirmation of screening results, 12.5% (95% CI=9.3-15.6%) did not, and 9.8% failed to respond to the follow-up survey. Factors independently associated with non-use of GP consultation for confirmation of screening results were self-reported unwillingness to consult a GP (adjusted odds ratio [OR]: 4.86, 95% CI=1.70-13.84), usual GP consultation frequency of less than once a year (adjusted OR: 4.13, 95% CI=1.56-10.97), and age 18-39 years (adjusted OR: 3.09, 95% CI=1.46-6.57). CONCLUSION: Home screening for glycemic abnormalities is a useful proximity health service for diabetes prevention in low socio-economic settings. Further efforts, including health literacy interventions, are needed to increase utilization of primary care.

Low seroprevalence of hepatitis E on Reunion island.

OBJECTIVE: Hepatitis E virus (HEV) has been scarcely investigated in the Indian Ocean. Following a nationwide serosurvey among blood donors, we conducted a population-based serosurvey to assess the magnitude of HEV exposure on Reunion Island. METHODS: Four hundred and sixty-six archived frozen human sera from the 2009 CoPanFlu-RUN cohort were analysed using the Wantai HEV IgG enzyme immunoassay. HEV seropositivity was defined as an IgG titre ≥5 UI/ml. Raw and weighted seroprevalences were assessed to account for the discrepancy between the CoPanFlu-RUN subset and the general community. Prevalence proportion ratios (PPR) were measured using log-binomial models. RESULTS: The raw and the weighted seroprevalences of HEV were 9.01% (95% CI 6.41-11.61) and 6.73% (95% CI 4.47-8.98), respectively. The presence of HEV IgG antibodies was associated with increasing age (P < 0.001). In a survey-adjusted model minimizing the sampling bias and adjusting for age, males were more likely to be seropositive than females (adjusted PPR 2.59, 95% CI 1.07-6.25). Seropositivity was spatially heterogeneous across the island (P < 0.01). Living in the neighbourhood of a pig farm within a low to intermediate slope area was associated with seropositivity in several models adjusting for age, gender, altitude of residency and interaction between slope and pig farms. CONCLUSION: Reunion Island is a low endemic area for HEV exposure. Despite limitations related to the retrospective study design, our findings confirm the roles of cumulative lifetime exposure and male gender in HEV exposure. The risk associated with neighbouring pig farms might also suggest environmental contamination in this setting.

Individualized Exercise Training at Maximal Fat Oxidation Combined with Fruit and Vegetable-Rich Diet in Overweight or Obese Women: The LIPOXmax-Réunion Randomized Controlled Trial.

OBJECTIVES: Lifestyle combined interventions are a key strategy for preventing type-2 diabetes (T2DM) in overweight or obese subjects. In this framework, LIPOXmax individualized training, based on maximal fat oxidation [MFO], may be a promising intervention to promote fat mass (FM) reduction and prevent T2DM. Our primary objective was to compare three training programs of physical activity combined with a fruit- and vegetable-rich diet in reducing FM in overweight or obese women. DESIGN AND SETTING: A five months non-blinded randomized controlled trial (RCT) with three parallel groups in La Réunion Island, a region where metabolic diseases are highly prevalent. SUBJECTS: One hundred and thirty-six non-diabetic obese (body mass index [BMI]: 27-40 kg/m2) young women (aged 20-40) were randomized (G1: MFO intensity; G2: 60% of VO2-peak intensity; G3: free moderate-intensity at-home exercise following good physical practices). OUTCOMES: Anthropometry (BMI, bodyweight, FM, fat-free mass), glucose (fasting plasma glucose, insulin, HOMA-IR) and lipid (cholesterol and triglycerides) profiles, and MFO values were measured at month-0, month-3 and month-5. RESULTS: At month-5, among 109 women assessed on body composition, the three groups exhibited a significant FM reduction over time (G1: -4.1±0.54 kg; G2: -4.7±0.53 kg; G3: -3.5±0.78 kg, p<0.001, respectively) without inter-group differences (p = 0.135). All groups exhibited significant reductions in insulin levels or HOMA-IR index, and higher MFO values over time (p<0.001, respectively) but glucose control improvement was higher in G1 than in G3 while MFO values were higher in G1 than in G2 and G3. Changes in other outcome measures and inter-group differences were not significant. CONCLUSION: In our RCT the LIPOXmax intervention did not show a superiority in reducing FM in overweight or obese women but is associated with higher MFO and better glucose control improvements. Other studies are required before proposing LIPOXmax training for the prevention of T2DM in overweight or obese women. TRIAL REGISTRATION: ClincialTrials.gov NCT01464073.

Predictors of Chikungunya rheumatism: a prognostic survey ancillary to the TELECHIK cohort study.

INTRODUCTION: Long-lasting relapsing or lingering rheumatic musculoskeletal pain (RMSP) is the hallmark of Chikungunya virus (CHIKV) rheumatism (CHIK-R). Little is known on their prognostic factors. The aim of this prognostic study was to search the determinants of lingering or relapsing RMSP indicative of CHIK-R. METHODS: Three hundred and forty-six infected adults (age≥15 years) having declared RMSP at disease onset were extracted from the TELECHIK cohort study, Reunion island, and analyzed using a multinomial logistic regression model. We also searched for the predictors of CHIKV-specific IgG titres, assessed at the time of a serosurvey, using multiple linear regression analysis. RESULTS: Of these, 111 (32.1%) reported relapsing RMSP, 150 (43.3%) lingering RMSP, and 85 (24.6%) had fully recovered (reference group) on average two years after acute infection. In the final model controlling for gender, the determinants of relapsing RMSP were the age 45-59 years (adjusted OR: 2.9, 95% CI: 1.0, 8.6) or greater or equal than 60 years (adjusted OR: 10.4, 95% CI: 3.5, 31.1), severe rheumatic involvement (fever, at least six joints plus four other symptoms) at presentation (adjusted OR: 3.6, 95% CI: 1.5, 8.2), and CHIKV-specific IgG titres (adjusted OR: 3.2, 95% CI: 1.8, 5.5, per one unit increase). Prognostic factors for lingering RMSP were age 45-59 years (adjusted OR: 6.4, 95% CI: 1.8, 22.1) or greater or equal than 60 years (adjusted OR: 22.3, 95% CI: 6.3, 78.1), severe initial rheumatic involvement (adjusted OR: 5.5, 95% CI: 2.2, 13.8) and CHIKV-specific IgG titres (adjusted OR: 6.2, 95% CI: 2.8, 13.2, per one unit increase). CHIKV specific IgG titres were positively correlated with age, female gender and the severity of initial rheumatic symptoms. CONCLUSIONS: Our data support the roles of age, severity at presentation and CHIKV specific IgG titres for predicting CHIK-R. By identifying the prognostic value of the humoral immune response of the host, this work also suggest a significant contribution of the adaptive immune response to the physiopathology of CHIK-R and should help to reconsider the paradigm of this chronic infection primarily shifted towards the involvement of the innate immune response.

Pandemic influenza due to pH1N1/2009 virus: estimation of infection burden in Reunion Island through a prospective serosurvey, austral winter 2009.

BACKGROUND: To date, there is little information that reflects the true extent of spread of the pH1N1/2009v influenza pandemic at the community level as infection often results in mild or no clinical symptoms. This study aimed at assessing through a prospective study, the attack rate of pH1N1/2009 virus in Reunion Island and risk factors of infection, during the 2009 season. METHODOLOGY/PRINCIPAL FINDINGS: A serosurvey was conducted during the 2009 austral winter, in the frame of a prospective population study. Pairs of sera were collected from 1687 individuals belonging to 772 households, during and after passage of the pandemic wave. Antibodies to pH1N1/2009v were titered using the hemagglutination inhibition assay (HIA) with titers ≥ 1/40 being considered positive. Seroprevalence during the first two weeks of detection of pH1N1/2009v in Reunion Island was 29.8% in people under 20 years of age, 35.6% in adults (20-59 years) and 73.3% in the elderly (≥ 60 years) (P<0.0001). Baseline corrected cumulative incidence rates, were 42.9%, 13.9% and 0% in these age groups respectively (P<0.0001). A significant decline in antibody titers occurred soon after the passage of the epidemic wave. Seroconversion rates to pH1N1/2009 correlated negatively with age: 63.2%, 39.4% and 16.7%, in each age group respectively (P<0.0001). Seroconversion occurred in 65.2% of individuals who were seronegative at inclusion compared to 6.8% in those who were initially seropositive. CONCLUSIONS: Seroincidence of pH1N1/2009v infection was three times that estimated from clinical surveillance, indicating that almost two thirds of infections occurring at the community level have escaped medical detection. People under 20 years of age were the most affected group. Pre-epidemic titers ≥ 1/40 prevented seroconversion and are likely protective against infection. A concern was raised about the long term stability of the antibody responses.

Perceived morbidity and community burden after a Chikungunya outbreak: the TELECHIK survey, a population-based cohort study.

BACKGROUND: Persistent disabilities are key manifestations of Chikungunya virus (CHIKV) infection, especially incapacitating polyarthralgia and fatigue. So far, little is known about their impact on health status. The present study aimed at describing the burden of CHIKV prolonged or late-onset symptoms on the self-perceived health of La Réunion islanders. METHODS: At 18 months after an outbreak of Chikungunya virus, we implemented the TELECHIK survey; a retrospective cohort study conducted on a random sample of the representative SEROCHIK population-based survey. A total of 1,094 subjects sampled for CHIKV-specific IgG antibodies in the setting of La Réunion island in the Indian Ocean, between August 2006 and October 2006, were interviewed about current symptoms divided into musculoskeletal/rheumatic, fatigue, cerebral, sensorineural, digestive and dermatological categories. RESULTS: At the time of interview, 43% of seropositive (CHIK+) subjects reported musculoskeletal pain (vs 17% of seronegative (CHIK-) subjects, P < 0.001), 54% fatigue (vs 46%, P = 0.04), 75% cerebral disorders (vs 57%, P < 0.001), 49% sensorineural impairments (vs 37%, P = 0.001), 18% digestive complaints (vs 15%, P = 0.21), and 36% skin involvement (vs 34%, P = 0.20) on average 2 years after infection (range: 15-34 months). After controlling for confounders such as age, gender, body mass index or major comorbidities in different Poisson regression models, 33% of joint pains were attributable to CHIKV, 10% of cerebral disorders and 7.5% of sensorineural impairments, while Chikungunya did not enhance fatigue states, digestive and skin disorders. CONCLUSIONS: On average, 2 years after infection 43% to 75% of infected people reported prolonged or late-onset symptoms highly attributable to CHIKV. These manifestations carry a significant burden in the community in the fields of rheumatology, neurology and sensorineural health.