Differences in cardiovascular risk factors in rural, urban and rural-to-urban migrants in Peru
- 1CRONICAS, Center of Excellence in Chronic Diseases, Universidad Peruana Cayetano Heredia, Lima, Peru
- 2Department of Medicine, School of Medicine, Universidad Peruana Cayetano Heredia, Lima, Peru
- 3Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, UK
- 4Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
- 5Área de Investigación y Desarrollo, A. B. PRISMA, Lima, Peru
- Correspondence to J Jaime Miranda, CRONICAS, Centro de Excelencia en Enfermedades Crónicas, Universidad Peruana Cayetano Heredia, Av. Armendáriz 497, 2do Piso, Miraflores, Lima 18, Peru;
Contributors JJM conceived the study, conducted the study and wrote the initial draft of this manuscript. RHG participated in the design of the study and actively supported the fieldwork phase of the study. LS contributed to the design and coordination of the study, and provided critical input during data analysis and interpretation of results. All authors read and approved the final manuscript. All authors had full access to all of the data in the study and can take responsibility for the integrity of the data and the accuracy of the data analysis. JJM is the guarantor of the study.
- Accepted 11 February 2011
- Published Online First 8 April 2011
Objectives To assess differences in cardiovascular risk profiles among rural-to-urban migrants and non-migrant groups.
Methods Cross-sectional study in Ayacucho and Lima, Peru. Participants were: rural (n=201); rural-to-urban migrants (n=589); and urban (n=199). Cardiovascular risk factors were assessed according to migrant status (migrants vs non-migrants), age at first migration, length of residency in an urban area and lifetime exposure to an urban area.
Results For most risk factors, the migrant group had intermediate levels of risk between those observed for the rural and urban groups. Prevalence for rural, migrant and urban groups was 3%, 20% and 33%, respectively, for obesity, and 0.8%, 3% and 6% for type-2 diabetes. This gradient of risk was not observed uniformly across all risk factors. Blood pressure did not show a clear gradient of difference between groups. The migrant group had similar systolic blood pressure but lower diastolic blood pressure than the rural group. The urban group had higher systolic blood pressure but similar diastolic blood pressure than rural group. Hypertension was more prevalent among the urban (29%) than both the rural and migrant groups (11% and 16%, respectively). For HbA1c, although the urban group had higher levels, the migrant and rural groups were similar to each other. No differences were observed in triglycerides between the three groups. Within migrants, those who migrated when aged older than 12 years had higher odds of diabetes, impaired fasting glucose and metabolic syndrome compared to people who migrated at younger ages. Adjustment for age, sex and socioeconomic indicators had little impact on the patterns observed.
Conclusions The impact of rural-to-urban migration on cardiovascular risk profile is not uniform across different risk factors, and is further influenced by the age at which migration occurs. A gradient in levels was observed for some risk factors across study groups. This observation indicates that urbanisation is indeed detrimental to cardiovascular health.
A data sharing technical appendix, statistical code and dataset available from the corresponding author ator . Consent for data sharing was not obtained but the presented data are anonymised and risk of identification is low.
Funding This work was funded in whole by the Wellcome Trust (GR074833MA). LS is supported by a Wellcome Trust Senior Research Fellowship in Clinical Science. The CRONICAS Center of Excellence in Chronic Diseases at UPCH is funded by the National Heart, Lung and Blood Institute (NHLBI), National Institutes of Health, Department of Health and Human Services, under contract No. HHSN268200900033C. The funder had no role in study design, data collection, analysis or interpretation; in writing the report; or in the decision to submit the article for publication. The researchers are all independent from the funding source.
Competing interests None.
Patient consent Obtained.
Ethical approval Ethical approval for this protocol was obtained from ethics committees at Universidad Peruana Cayetano Heredia in Peru and the London School of Hygiene and Tropical Medicine in the UK. The purpose of the study was explained to each of the study participants and written informed consent was obtained.
Provenance and peer review Not commissioned; externally peer reviewed.