The impact of multiple blood donations on the risk of cardiovascular diseases: Insight of lipid profile

Blood donation improves skin aging through the reduction of iron deposits and the increase of TGF-β1 in elderly skin

Skin aging is characterized by a wide range of physiological and structural changes, including wrinkling, dyschromia, and roughness, as well as the reduction of dermal thickness and collagen content. Here, we showed that blood donation increased dermal thickness and collagen content and decreased the number of senescent cells in old mice. Transcriptomic and metabolomic studies revealed blood donation significantly altered aging-related pathways in the skin of old mice. Molecular genes analysis indicated blood donation decreased the expression of genes associated with inflammation such as Fols1, Cox-2, and IL-1β, and increased the expression of collagen-associated genes including TGF-β1, TGF-β2, and Col3a1. The improvement of skin aging by blood donation was associated with the reduction of iron deposits and the increase of TGF-β1 in elderly skin. Our results suggested that appropriate blood donation could promote collagen re-synthesis and improve skin aging.

Cohort Profile: The Shaanxi Blood Donor Cohort in China

Purpose

The Shaanxi Blood Donor Cohort was set up to investigate the impact of blood donation on the health of donors compared with non-blood donors. The specific aims of the study include (1) identifying the geographical and temporal trends of incidence for diseases in both blood donors and non-blood donors; (2) assessing the impact of environmental exposures, lifestyle, body mass index (BMI) and blood type on disease burdens, stratified between blood donors and non-blood donors; and (3) among blood donors, investigating if regular blood donation has a positive impact on donors’ health profiles, based on a cohort with a mixed retrospective and prospective study design.

Participants

A total of 3.4 million adults, with an equal number and identical demographic characteristics (year of birth, sex and location of residence) of blood donors and non-blood donors, were enrolled on 2012. The one-to-one matching was conducted through a repeated random selection of individuals without any history of blood donation from the Shaanxi Electronic Health Records. The cohort has been so far followed up to the end of 2018, summing to nearly 24 million years of follow-up. The cohort will be followed up prospectively every 3 years until 2030.

Findings to Date

Of the 1.7 million blood donors, 418,312 (24.5%) and 332,569 (19.5%) individuals were outpatients and inpatients, accounting for 1,640,483(96.2%) outpatient and 496,061 (29.1%) inpatient visits. Of the same number of non-blood donors, 407,798 (23.9%) and 346,097 (20.3%) individuals were hospital outpatients and inpatients, accounting for 1,655,725 (97.1%) outpatient and 562,337 (33.0%) inpatient visits. The number of outpatient and inpatient visits by non-blood donors was 0.9 and 3.9% higher than those of the blood donors (p < 0.01). Blood donors demonstrate significantly fewer inpatients visits than non-blood donors for major chronic disease categories (p < 0.01).

Future Plans

We are currently exploring the long term benefits of blood donation on major chronic disease categories and multimorbidities in this large population cohort. The study results are adjusted by the “healthy donor effect.” This cohort study will continue until 2030.

Cardiovascular risk in 159 934 frequent blood donors while addressing the healthy donor effect

OBJECTIVE

To investigate whether regular blood donation decreases cardiovascular risk.

METHODS

All 159 934 Dutch whole-blood donors with an active donation career of at least 10 years were categorised into sex-specific donation tertiles based on the number of donations during this 10-year qualification period. Cardiovascular endpoints were based on hospital discharge diagnoses and death certificates from Dutch Hospital Data and Statistics Netherlands and occurring after the 10-year qualification period. Cox regression was used to estimate the age-adjusted and starting year-adjusted hazard rate ratio (HRR).

RESULTS

Female high-frequency blood donors had a reduced cardiovascular morbidity (HRR=0.91, 95% CI 0.85 to 0.98) compared with low-frequency blood donors. No effect was observed in men (HRR=1.00, 95% CI 0.95 to 1.05). To rule out a residual healthy donor effect (HDE), additional sensitivity analyses using a 5-year qualification period were conducted. The results supported the absence of a residual HDE.

CONCLUSIONS

This study showed a protective effect of long-term, high-frequency blood donation against cardiovascular disease. This effect was only observed in women and not in men.