Assessment of the Role of Selected Comorbidities on Overall -and Cardiovascular Mortality in Southern Kazakhstan: A 12-Years Follow-Up Study

Abstract

The aim of the study was to assess survival of patients with isolated and combined disorders of circulatory system and diabetes mellitus in Turkestan region, Southern Kazakhstan. Altogether, 1 143 randomly selected individuals comprised a cohort, which was followed up from 2003 through 2015. Data on diagnosis, age, gender, body mass index, smoking and alcohol consumption were collected by trained medical interviewers. Bivariate comparisons of survival between groups with no cardiovascular diseases and groups with isolated and combined disorders were performed using Kaplan-Meier analysis. Independent associations between the studied factors and overall mortality as well as mortality from cardiovascular causes were assessed using Cox regression. Crude and adjusted hazard ratios (HR) were calculated with 95 % confidence intervals (CI). The overall mortality in the cohort was 145 per 1 000 with cardiovascular causes accounting for 49 % of deaths during the study period. The risk of death from any cause was increased for individuals who had arterial hypertension and diabetes mellitus (HR = 4.6, 95 % CI: 1.4-15.3) and combined arterial hypertension, cardiac ischemia and diabetes mellitus (HR = 7.0, 95 % CI: 2.1-26.1) in fully adjusted Cox regression model. The risk of cardiovascular death was increased among patients with isolated cardiac ischemia (HR = 2.7, 95 % CI: 1.1-6.8) and among those with combined arterial hypertension and diabetes mellitus (HR = 8.7, 95 % CI: 2.5-30.4) adjusted for gender, age, smoke, alcohol consumption and body mass index. Combined disorders of circulatory system and diabetes mellitus considerably increase the risk of death in Turkestan region, Southern Kazakhstan warranting urgent need for evidence-based treatment of comorbidities and development of preventive programs.