Disease relevance of Cohort Effect

• As well as the birth cohort effects, there was some evidence of a recent overall decline in mortality rates in several countries, e.g. Austria, FRG, Greece and the UK, and this may be due to an increase in survival resulting from improved management and treatment of women with breast cancer [1].
• Previous discussions have indicated that the small increases of risk of venous thromboembolism (VTE) associated with newer combined oral contraceptives (third generation, containing desogestrel and gestodene) may be attributed to bias due to cohort effects [2].

High impact information on Cohort Effect

• Consecutive saline/GHRH infusion elicited comparable peak (absolute maximal) serum GH concentrations (micrograms per liter) in the three study groups, i.e. 18 +/- 5.0 (PP), 9.6 +/- 1.7 (MP), and 14 +/- 5.3 (YM) (each P < 0.01 vs. saline; P = NS cohort effect) [3].
• Age-related decreases in the prevalence of myopia: longitudinal change or cohort effect [4]?
• Generation effects on the microstructure and product distribution in ethylene polymerization promoted by dendritic nickel catalysts [5].
• Methodologic issues in studies of mortality following epilepsy: measures, types of studies, sources of cases, cohort effects, and competing risks [6].
• Attributable fractions for stillbirth because of age, period, and cohort effects were 16.5%, 24.9%, and 0.1%, respectively, among Black women and 14.5%, 36.2%, and 2.1%, respectively, among White women [7].

Biological context of Cohort Effect

• For the generation effect, average systolic blood pressure decreased in all countries, with the exception of men aged 50-59 in Serbia and men aged 75-84 in The Netherlands. Average serum cholesterol uniformly increased in men aged 50-59 for the younger age-class and slightly decreased in men aged 75-84 [8].

Associations of Cohort Effect with chemical compounds

• All analyses suggest that the dramatic decline in detected cocaine use among arrestees--from 69% in 1987 to 17% in 1993--was a cohort effect [9].
• Longitudinal analysis also suggested a birth cohort effect except for the triglyceride level for women [10].
• Parental and first generation effects of exogenous 17beta-estradiol on reproductive performance of female zebra finches (Taeniopygia guttata) [11].
• Our results are in accordance with the increase in metronidazole resistance of H. pylori stains and the cohort effect of H. pylori infection on the elderly Israeli-born population [12].
• With cohort effects statistically controlled, there was a negative correlation between latency to fall asleep and CSF 5-HIAA concentrations (i.e., subjects with high CSF 5-HIAA concentrations were more likely to fall asleep early) [13].

Gene context of Cohort Effect

• Contrary to previous reports, the DAT groups showed the generation effect, that is, better recognition for participant-generated words than experimenter-generated words (Task 1) or read words (Task 2) [14].
• For DBP, there were cohort effects (significant sibling and spouse but not parent-offspring correlations) in the complete and normotensive samples that may be due to generation-specific environmental influences [15].
• APC modelling suggested an increasing cohort effect (adjusted for both age and period) from the birth cohort 1950-54 onwards [16].
• Poisson regression was used to distinguish a cohort effect from a time-period effect on the incidence of HCC [17].
• CONCLUSIONS: The generation effect was present in MS and control subjects and may be a viable way of maximizing new learning in MS [18].

Analytical, diagnostic and therapeutic context of Cohort Effect

• The relationship between change in warfarin dose requirements and ageing established in this longitudinal study is in good agreement with that established by cross-sectional studies, suggesting that no major birth cohort effect is influencing requirements in our warfarin-treated population [19].

References