Epidemiology: a tool for the assessment of risk

The purpose of this chapter is to introduce and demonstrate the use of a key tool for the assessment of risk. The word epidemiology is derived from Greek and its literal interpretation is 'studies of people'. A more usual definition, however is the scientific study of disease patters among populations in time and space. This chapter introduces some of the techniques used in epidemiology studies and illustrates their uses in the evaluation or setting of microbiological guidelines for recreational water, wastewater reuse and drinking water

Anthropometric trends and the risk of cardiovascular disease mortality in a Lithuanian urban population aged 45-64 years

To estimate trends in anthropometric indexes from 1992 to 2008 and to evaluate the risk of cardiovascular disease mortality in relation to anthropometric indexes (body mass index, waist circumference, waist:hip ratio, waist:height ratio)

Socio-economic status over the life-course and depressive symptoms in men and women in Eastern Europe

Objective: Research into social inequalities in depression has studied western populations but data from non-western countries are sparse. In this paper, we investigate the extent of social inequalities in depression in Eastern Europe, the relative importance of social position at different points of the life-course, and whether social patterning of depression differs between men and women.Method: A cross-sectional study examined 12,053 men and 13,582 women in Russia, Poland and the Czech Republic. Depressive symptoms (16 or above on the CESD-20) were examined in relation to socio-economic circumstances at three phases of the life-course: childhood (household amenities and father's education); own education; current circumstances (financial difficulties and possession of household items).Results: Pronounced social differences in depression exist in men and women throughout Eastern Europe. Depression was largely influenced by current circumstances rather than by early life or education, with effects stronger in Poland and Russia. Odds ratios in men for current disadvantage were 3.16 [95% CI: 2.57-3.89], 3.16 [2.74-3.64] and 2.17 [1.80-2.63] in Russia, Poland and the Czech Republic respectively. Social variables did not explain the female excess in depression, which varied from 2.91 [2.58-3.27] in Russia to 1.90 [1.74-2.08] in Poland. Men were more affected by adult disadvantage than women, leading to narrower sex differentials in the presence of disadvantage.Limitations: Cross-sectional data with recall of childhood conditions were used.Conclusion: Current social circumstances are the strongest influence on increased depressive symptoms in countries which have recently experienced social changes. (C) 2007 Elsevier B.V. All rights reserved

Association between fasting plasma triglycerides, all-cause and cardiovascular mortality in Czech population. Results from the HAPIEE study

Dyslipidemia is the risk factor of cardiovascular disease, but the relationship between the plasma triglyceride (TG) levels and total/cardiovascular mortality has not yet been analyzed in Slavs. The aim of our study was to analyze the association between the fasting TG levels and all-cause/cardiovascular mortality. We have examined 3,143 males and 3,650 females, aged 58.3+/-7.1 years. 729 deaths (274 cardiovascular deaths) have been registered during up to 11.8 years of follow-up. Age-sex adjusted all-cause mortality was higher in individuals with TG values 3.01-4.00 mmol/l (HR 1.37, 95 % CI 1.02-1.83, P=0.035) and over 4.00 mmol/l (HR 1.66, 95 % CI 1.21-2.27, P=0.002) when compared with a reference group (TG 1.41-1.80 mmol/l). Elevated risk remains significant when adjusted for education, marital status and unemployment. When further adjusted for smoking, BMI and dyslipidemia interventions, HR for those in above 4.00 mmol/l group decreased (1.42, P=0.04). The results have been similar when cardiovascular mortality has been examined, however, results reached statistical significance only for the TG over 4.0 mmol/l (P=0.028). Our results confirmed that enhanced plasma levels of plasma triglycerides are dose dependently associated with increased risk of all-cause mortality, however, it seems that individuals with TG values 1.8-3.0 mmol/l are not in higher risk of death

The association between APOA5 haplotypes and plasma lipids is not modified by energy or fat intake: The Czech HAPIEE study.

Several smaller studies reported interactions between dietary factors and apolipoprotein A5 (APOA5) gene polymorphisms in determination of plasma lipids. We tested interactions between APOA5 haplotypes and dietary intake in determination of plasma triglycerides (TG) and other lipids

Correlates of depressive symptoms in urban middle-aged and elderly Lithuanians.

The study aimed to examine the prevalence of depressive symptoms and their correlates in urban middle-aged and elderly Lithuanian adults

Nobody Is Perfect: Comparison of the Accuracy of PCR-RFLP and KASP (TM) Method for Genotyping. ADH1B and FTO Polymorphisms as Examples

DNA genotyping is among the most common analyses currently performed in scientific research. Two high-throughput genotyping techniques are widely used – the “classic” PCR-RFLP and probe-based methods such as TaqMan® PCR assay or KASP™ genotyping. The probe-based techniques are claimed to be more accurate than PCR-RFLP; however, the evidence for this claim is sparse. We have directly compared results of genotyping of two SNPs (rs1229984 and rs17817449) obtained by the PCR-RFLP and KASP™ in 1,502 adult Caucasians. The results were identical in 97.3 % and 95.9 % cases, respectively. Discrepancies (either different results or result obtained with one but not with the other method) were addressed by confirmatory analysis using direct sequencing. The sequencing revealed that both methods can give incorrect results, but the frequency of incorrect genotyping of rs1229984 and rs17817449 was very low for both methods – 0.1 % and 0.5 %, respectively, for PCR-RFLP and 0.1 % and 0.3 %, respectively, for KASP™. These results confirm that the KASP™ technique is slightly more accurate, but it achieves slightly lower call rates than PCR-RFLP. When carefully set up, both PCR-RFLP and KASP™ could have accuracy of 99.5 % or higher

Prevalence, awareness, treatment and control of dyslipidemia in older persons in urban and rural population in the Astana region, Kazakhstan.

BACKGROUND: Despite high cardiovascular mortality in Central Asian republics of the former Soviet Union, there is limited information about major risk factors, including blood lipids. We investigated the prevalence of impaired concentrations of blood lipids, the awareness, treatment and control of hypercholesterolemia, and factors associated with these indicators in urban and rural populations in Kazakhstan. METHODS: We conducted a cross-sectional study of random urban and rural population samples (the state capital Astana and Akmol village). Men and women aged 50-74 years were examined; a total of 954 adults participated (response rate 59%). Serum concentrations of total, LDL and HDL cholesterol and triglycerides and a range of other cardiovascular risk factors were measured. RESULTS: The overall prevalence of hypercholesterolemia (total cholesterol ≥6.2 mmol/l) was 37%; among subjects with hypercholesterolemia, 57% were aware of their condition, 41% took medication and 23% had total cholesterol <6.2 mmol/l (4.5% <5 mmol/l). The prevalence, awareness, treatment, and control of hypercholesterolemia were all higher in the urban than the rural area. Similarly, the proportions of subjects with impaired concentrations of specific lipids fractions were also considerably higher in the urban population. Most associations with other covariates were in the expected direction. CONCLUSIONS: This study found relatively high prevalence of dyslipidemia in the Kazakh population, and the blood lipid profile was less favourable in the urban area. These pronounced urban-rural differences may be related to urbanization, the associated nutrition transition and to access to health care

Education, material condition and physical functioning trajectories in middle-aged and older adults in Central and Eastern Europe: a cross-country comparison

BACKGROUND: Two competing hypotheses, cumulative advantage/disadvantage and age-as-leveller, have been proposed to explain the contradictory findings on socioeconomic differences in health over the lifespan. To test these hypotheses, this investigation examined the influence of educational attainment and material condition on individual trajectories of physical functioning (PF) in unexplored ageing populations in Central and Eastern Europe. METHODS: 28 783 men and women aged 45–69 years selected from populations in seven Czech towns, Krakow (Poland) and Novosibirsk (Russia). PF was measured by the Physical Functioning Subscale (PF-10) of the Short-Form-36 questionnaire (SF-36) at baseline and three subsequent occasions. The highest educational attainment was self-reported at baseline, and material condition was captured by the sum score of 12 household amenities and assets. RESULTS: In all cohorts, participants with a university degree had the highest PF-10 score at baseline and slowest rate of decline in the score during follow-up, while the lowest baseline scores and fastest decline rate were found in participants with less than secondary education in all cohorts and in Russians with secondary education. Similar disparities in the baseline PF-10 score and decline rate were observed across tertiles of material condition, but differences in decline rates across the three tertiles among Czechs or between the lower two tertiles among Russians were not statistically significant. CONCLUSIONS: Disparities in PF by educational attainment and material condition among middle-aged and older adults in Central and Eastern Europe existed at baseline and widened during ∼10 years of follow-up, supporting the cumulative advantage/disadvantage hypothesis

APOE polymorphism and its effect on plasma C-reactive protein levels in a large general population sample

The literature on association between apolipoprotein E (APOE) gene variations and plasma levels of C-reactive protein (CRP) remains inconsistent, mainly due to low statistical power of previous studies. To clarify this question, we analysed data from large population sample of randomly selected individuals from 7 Czech towns (2886 males and 3344 females, the HAPIEE study). In both males and females, the lowest levels of plasma hsCRP were observed in the carriers of the APOE ε4ε4 and ε4ε3 genotypes. The median (inter-quartile range, IQR) concentration of hsCRP in carriers of the most common APOE ε3ε3 genotype (two thirds of participants) was 1.13 (IQR 0.56; 2.33) mg/l in men and 1.23 (IQR 0.61; 2.65) mg/l in women, compared with 0.72 (IQR 0.61; 0.86) mg/l in male and 0.72 (IQR 0.61-0.85) mg/l in female carriers of APOE ε4ε3/ε4ε4 genotypes; the differences were statistically significant (p<0.001). The association between APOE and CRP was not materially affected by adjustment for age, sex, history of cardiovascular disease or cardiovascular risk factors. This study, the largest to date, provides robust evidence of an association between plasma hsCRP and the APOE genotype, an association not explained by history of cardiovascular disease nor its risk factors