Association of socioeconomic status with overall and cause specific mortality in the Republic of Seychelles: results from a cohort study in the African region

PLoS One. 2014 Jul 24;9(7):e102858. doi: 10.1371/journal.pone.0102858. eCollection 2014.


Background: Low socioeconomic status (SES) is consistently associated with higher mortality in high income countries. Only few studies have assessed this association in low and middle income countries, mainly because of sparse reliable mortality data. This study explores SES differences in overall and cause-specific mortality in the Seychelles, a rapidly developing small island state in the African region.

Methods: All deaths have been medically certified over more than two decades. SES and other lifestyle-related risk factors were assessed in a total of 3246 participants from three independent population-based surveys conducted in 1989, 1994 and 2004. Vital status was ascertained using linkage with vital statistics. Occupational position was the indicator of SES used in this study and was assessed with the same questions in the three surveys.

Results: During a mean follow-up of 15.0 years (range 0-23 years), 523 participants died (overall mortality rate 10.8 per 1000 person-years). The main causes of death were cardiovascular disease (CVD) (219 deaths) and cancer (142 deaths). Participants in the low SES group had a higher mortality risk for overall (HR = 1.80; 95% CI: 1.24-2.62), CVD (HR = 1.95; 1.04-3.65) and non-cancer/non-CVD (HR = 2.14; 1.10-4.16) mortality compared to participants in the high SES group. Cancer mortality also tended to be patterned by SES (HR = 1.44; 0.76-2.75). Major lifestyle-related risk factors (smoking, heavy drinking, obesity, diabetes, hypertension, hypercholesterolemia) explained a small proportion of the associations between low SES and all-cause, CVD, and non-cancer/non-CVD mortality.

Conclusions: In this population-based study assessing social inequalities in mortality in a country of the African region, low SES (as measured by occupational position) was strongly associated with overall, CVD and non-cancer/non-CVD mortality. Our findings support the view that the burden of non-communicable diseases may disproportionally affect people with low SES in low and middle income countries.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Binge Drinking / epidemiology
  • Cardiovascular Diseases / mortality*
  • Cardiovascular Diseases / pathology
  • Cause of Death
  • Cohort Studies
  • Developing Countries
  • Diabetes Mellitus / epidemiology
  • Female
  • Humans
  • Hypercholesterolemia / epidemiology
  • Hypertension / epidemiology
  • Male
  • Middle Aged
  • Neoplasms / mortality*
  • Neoplasms / pathology
  • Obesity / epidemiology
  • Risk Factors
  • Seychelles / epidemiology
  • Smoking / epidemiology
  • Social Class*
  • Survival Analysis

Grants and funding

SS is supported by an Ambizione Grant (n ° PZ00P3_147998) from the Swiss National Science Foundation (SNSF) and was supported by a fellowship awarded by the Swiss School of Public Health (SSPH+) during the preparation of this manuscript. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.